Hey guys I really need help diagnosing whatever the hell is going on with my truck.
It's a 91 short bed 1/2 ton 4x4 truck.
I have a 300hp crate 360 magnum in it, I have a non lock up A-518 trans in it.
I have a very strabge vibration issue going on, in every gear I get a vibration that comes on at about 2500rpm and it's at it's worst at 2500-2800 rpm then it some what smooths out if i step on it a little more, but it's still there, at higher rpm it just seems like it takes longer to circulate if that makes sense.
This vibration at 2500 rpm is like a quick womp womp womp womp type vibration, I can feel it in the gas pedal and in the steering wheel.
For the longest time I thought it was drivetrain related, but I'm realizing that isn't the case because of how it's rpm sensitive and speed sensitive.
It still vibrates the same even in park or nuetral.
Transmission was re-built a few years ago and the dumb asses at the shop put the wrong converter on it, they put an la 360 converter on it and I caught that fairly quick.
They then put the correct converter on and I thought all was well there, trans shifts fine, no leaks anywhere, I don't see any abnormal amount of wobbling at the converter and flex plate while idling or while holding it at 2500 rpm.
I don't hear any strange noises coming from the transmission area and converter area.
I'm at a loss with what's causing this.
Brand new alternator and ps pump and brackets, new belts, I've removed the belts and the vibration is still there, new radiator fan, no fan clutch, I don't see any strange wobbling at the harmonic balancer and it is the original
Balancer that came with the engine from mopar.
I'm about ready to pull my hair out over this vibration and I don't know where to start.
I was thinking start at ignition since that's easy and cheap, I tested my ignition coil which is a crane cams lx91 e-core style coil, the numbers are .07 for primary resistance and 4800k for secondary resistance.
The ignition is brand new, crane cams hi-6 cd ignition, rev limiter is set to 6200 rpm.
Distributor is a brand new firecore 50, timing is 16 initial and 32 total.
I'm out of ideas and need some advice or some strategy to pin point whatever this is.
Oil pressure on engine is good, don't hear any strange knocking sounds or anything like that.
The last warm compression test I did each cylinder was at 150 psi, that was done while engine was at operating temp and last time i did it was a couple years ago.
I can perform another one if need be.
Please help.

unless it is an ign misfire & I have my doubts, it is strickly eng related, are you sure the right TC/dampener are on there? unless the factory balancing is way off but I'd think the above first.

Yes I can post pictures of them if you'd like me to.
I've verified the converter is the correct converter for the 360 magnum, it's dark maroonish red with the weight on the one side of it.
The flex plate is an La style flex plate.
I tried posting pics and it wants me to use a URL?

Once you enter the verbiage into the box, click on "File Manager" right below the text box then upload pics. Using the image link above the text box requires an externally hosted pic.

I'm using an iPhone, does that make a difference?

Here is some info that my brother Dog posted awhile back: 5.9 mag balance is different from a LA 360. 5.9 uses an OE 5.9 flexplate/neutral converter. magnum imbalance is in the flexplate. LA 360 imbalance is in the converter. You've got some of this covered/dealt with but I wanted to get it out all there (more info the better). EDIT after (re)reading I wonder if they used the common LA plate as opposed to the 5.9 specific one?

Yes it looks like the common la flex plate with the magnum weighted converter.
Which from my understanding works, it can work both ways, you can use a nuetral balance converter with the magnum weighted flex plate or you can use the stock la flex plate with the weighted magnum converter.
From my understanding Chrysler did it both ways, the early 93-95 magnums got the la flex plate with the magnum weighted converter and then in 96 they started using the nuetral converter and magnum weighted flex plate.

.

Are you sure it's a 5.9? My 400 Ford $500 pickup was really a 351M as I found out when the 400's pressure plate wouldn't work on the flywheel. Later I discovered that it was a 4" stroke so it really was a 400 by means of a crank and piston swap. So it could be a 5.2 masquerading as a 5.9. That seems pretty unlikely but a lot can change in 20+ years.

It's not the ignition but the real way to find that out is to use a timing light on each spark plug lead and watch the flashes. Even at 3000rpm, a miss in the flash pattern is pretty easy to see. Once you have put the ignition to rest, everything else you said points to a fundamental balance issue.

That means it must be something attached to the crankshaft. Period.

When you wisely ran the engine without the belts and the vibration was still there, it eliminated everything that was not attached to the crankshaft at that moment.

The description of the vibration being worse through a band of rpm is right in line with descriptions of 360s with 318 converters or neutral balance flywheels.

It helps if we stop referring to a 5.9Mag motor as a 360. Magnum engines have enough different parts that even though they share bore and stroke with certain LA engines, they are not LA engines.

It is important to restate that the values for factory imbalance in 360s and 5.9Mags is different. The 5.9Mag uses a smaller amount of imbalance.

IMHO you will be removing the engine and discovering which of the several incorrect combinations you have.

Good Luck!

R.

Im absolutely 110 percent positive it is a 360 magnum.
I still have the receipt from the dealership my dad bought it from as well as the installation instructions.
It's a 300 hp crate 360 magnum purchased in march of 2003.
I don't think I'll need to remove the engine to figure out what's going on, maybe the transmission to see if the flex plate is bent or broken.
I will go around the converter to flex
Plate bolts and make sure they are tight.
The shop that did the transmission wasn't exactly sloppy, they were just over confident not listening to me when I said it's a magnum so the balance is different.
They acted like it was your standard 360 and put that converter on it.
They fixed it without charge once they realized the bad made a mistake.
The timing light on each plug wire is a good idea.
What do I look for in the light strobe to see if one of them is Miss firing.
I was also thinking I could have it put on a scope to watch the ignition events to verify if all 8 cylinders are firing correctly.
Could it be a damaged plug wire that's causing this? Could the ignition coil it's set cause this? It's literally rough feeling at about 2500 rpm, the higher I rev the engine the slower the vibration is to come around.
I know the harmonic balancer on the front of the engine is correct, and I know it's a 5.9 magnum without a doubht.

with it up on a fast enough idle so it is in that rough idling zone, put the clamp on each plug wire one at a time & squeeze & hold the trigger on the gun & look at the blinking light to see if it "misses".

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Sometimes it's the simplest of things, your driveline "vibration" sounds just like the "shop truck" I bought off a bunch of ASE Certified mechanics who did an engine swap/torque converter swap and could never figure out the cause of the slight driveline vibration, so they "dumped" the truck on me, after 5 minutes of ownership, it was "cured"....firing order, 2 cylinders crossed wires, 4 ASE mechanics and a month of on and off troubleshooting, they over looked the obvious....so rule out the simple things before you go tearing stuff apart

Deffenitley, that's why I'm going to rule out ignition first.
In almost wondering if it's a bad plug wire or if it's my ignition coil.
The coil in running was in a truck that had caught on fire.
My dad had a 75 w100 and the wiring at the amperage gauge caught on fire and that's what burned down the cab.
They got the fire put out before it damaged the engine and under the hood.
But I'm wondering if maybe that coil got hot in that fire and it works but not exactly like it's supposed too.
I'm not sure if a single coil system like mine can affect an individual cylinder or two, but the last time I had my spark plugs out cylinder 7 and cylinder 8's spark plug were questionable.
Not fouled but looked like they weren't firing as well as the other plugs were.
Could a coil cause something like that to happen if it's on it way out?
Something is telling me to try a new coil just because of what I seen with number 7 and number 8 plugs and the fact that the coil I'm running was on a truck where the cab burned down.
The ignition in running is a crane cams hi-6 cd ignition box with the crane cams lx91 e-core coil. I measured the coils resistance and didn't see anything that jumped out at me really.
I guess you could say the secondary resistance of the coil was a little low at 4800 and the primary resistance was .07-1.0 which is ok.
I've been trying to find online what my specific coils resistance should measure out at.
Plug wires are Taylor thundervolt 8.2mn, they are only a couple years old but some of the boots are torn from taking them on and off as much as I have over the years.
Maybe this issue is ignition, it's just strange how it runs so smooth untill 2500 rpm and then all hell breaks loose with the vibrations.
I thought it was drivetrain related for the longest time, but being that it's strictly rpm dependent I've changed my mind.
That and I'm running a 500 dollar 1350 series cv shaft with all spicer yokes and u-joints and my pinion is 1-2 degrees below inline with the shaft which is exactly where you want it to be with a cv shaft.
All U-joints are tight, and output shaft bearing on t-case is tight.

Is it possible for a single coil system to only affect a couple cylinders? It should affect all cylinders not just one right?
I'm thinking maybe the coil is fine below 2500 rpm but at 2500 and up it starts acting up and that's what I'm feeling?
Like I said Idk, I tested resistance to the coil and primary reisistance is .07-1.0 and the secondary resistance is 4700-4800.
Maybe I should my plug wires and start testing the resistance on them, maybe I have one that just went haywire and it's causing bad missfires.
I haven't been able to even look at the truck the last couple
Of days I've been so pissed off at it, but I'm going to start poking around tonight.
I'm going to start with hooking my timing light up to each plug wire and seeing what the strobe looks like at 2500 rpm.
I'm really hoping this is just an ignition issue, if it is at the trans then I suspect the flex plate because I know the converter is correct, I've compared it to pictures of the magnum weighted converters and it looks identical.
And if it was the wrong converter wouldn't i fee that vibration all the time including at idle?
And also if the flex plate was bent bad enough to cause this vibration wouldn't I see some
Wobble to it?
I had my wife hold the throttle at 2500 rpm in nuetral and I couldn't see anything abnormal at the converter and flex plate.
Looked completely normal. No wobbling, no strange sounds, nothing.

external parts "Wobbling" from loose/eccentric/out of round parts would be different/visible on that specific part as opposed to vibration coming from the crank being out of balance either from the wrong tc/plate or wrong bobweight amt when it was balanced.

In these pictures you'll see I have the correct magnum weighted torque converter, first picture is my torque converter, second picture is from a guy o line that pulled a factory trans from a 1995 Dodge Ram 2500 with a 5.9 magnum.
My converter looks identical, the weight looks the exact same.
Third picture is a little crack that I found in my converter by the teeth where the starter Engadges, I'm going to guess that the starter was sticking at some point and smacked the teeth on the converter while the engine was running and that caused this crack.
I don't think it's causing my vibration but it will need to be addressed at some point.


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I don't understand what's going on? It asks for a URL I give it one and it's still no good?
Wish is could be as easy as other sites where you just upload a pic straight from your phone to the page.

It's most definelty a miss fire, I've confirmed that this evening.
When I hold the throttle at 2400-2600 rpm you can hear it in the exhaust.
I checked all my plugs, they appear to be ok, I've ohmed out all my spark plug wires, they check out.
Idk where to start, distributor is brand new firecore 50, I've verified timing, my balancer is correct, I've verified that with a piston stop.
The light on My crane cams hi-6 cd ignition box starts cutting in and out a little bit while the miss fire is happening.
Could it be a poor ground on the cd box? The rev limiter malfunctioning?
This is really bizzar, it idles smooth, but the second you start putting
A load on it it starts Miss firing and popping out the exhaust.

Much better this than a balancing issue!. Check my baby (Rotor Phasing) as a potential. check dist reluctor gap & it might also be the box. EDIT & the plugs are good right? vac leak?

I checked the reluctor gap and it was perfect,
I am thinking it's an issue inside the crane cams hi-6 cd ignition box, when I hold the throttle at 2500 rpm and it's Miss firing I can see the red light on the box cutting in and out getting brighter then dimmer then brighter then dimmer and the ignition box it's self gets pretty warmt the touch At the exact same time this is happening.
I suspect ether my ground isn't quite good enough, or this box just has some internal issue.
I've had this issue ever since I put this box in my truck and the entire time I thought it was drivetrain related.
The ground wire on this ignition box is only about 6-8 inches long, and I have the ignition box mounted behind my seat in the cab to keep it out of the weather, for a ground I just drilled a hole behind the seat and put screw there to hold it.
It could also be the ignition coil it's self though right? I just don't understand how it could be the coil when it appears to ohm out just fine with my multimeter when I check the resistance.

Did it start right when the box was swapped in? & I'm assuming there were other changes done at the same time which would have kept a person from seeing the obvious, that it was the new device, the box. Usually a bad coil that will run, The eng starts to run miss or just dies after it gets warm.

This has been an issue for awhile, I can't exactly pin point if this happened imidiatley following the install of this crane ignition box, but the way it's feeling really warm to the touch especially when I'm holding the throttle at the rough spot where it's Miss firing just really makes me think whatever is causing the miss fire is inside the cd ignition box it's self.
I wish I had a way of confirming it but the only thing I can really do is try grounding the ignition box directly to the negative post on the battery and seeing if it gets better, if it doesn't then I can try a different coil, if that doesn't work then I'll have to replace the cd ignition box with a different one and see what that does.
I've ohmed all my spark plug wires, they all check out, plugs look good, distributor cap is brand new so is the rotor, distributor it's self is brand new, timing is correct, timing marks have been verified with Piston stop, pick up coil ohms out great.
It's really gotta be in this crane cd ignition box, it seriously kind of seems like the rev limiter is glitching in and out, I'm going to dis-connect the rev limiter and see if the issue remains tomorrow along with grounding the cd ignition box directly to negative post on the battery.

What I would do is sub back in the regular Mopar ign (dist if needed to be changed, a regular ECU/coil) & see if it straightens out. you could make up some jumpers with alligator clips on the ends for easy connections & you'll have an ans in no time.

Wow, I would have been wiling to bet quite a bit on crankshaft balance. All the classic symptoms were there.



The coil - put the ohmmeter across the two input terminals, you say it is. Next put one ohmmeter in the plug wire hole and the other to a bare spot on the coil If you have continuity it's okay, too. I have never heard of coils cutting out at certain rpm levels.

You have checked continuity of all plug wires and they are all able to conduct electricity.

You have checked continuity of the pickup coil, and it's good.

Have you checked the spark plugs? Occasionally one is bad right out of the box.

You have wired the heavy red wire to battery positive post, connected ignition box to cab. So what connects the cab to the battery, ground-wise? Running a black wire all the way to battery negative is a good way to find out about the grounds. You have mounted the box in the cab. What kind of wire is the signal coming through from the distributor pickup coil? You have a moderately long pickup coil lead and it could be giving you troubles. For example, under certain conditions the pickup wire can act as an antenna and the voltage it gathers can fool the sensor circuit in the ignition box. Under other conditions the pickup coil lead may make a capacitor with the floor sheetmetal. This could be enough to send the system into oscillation.

I'd suggest a twisted shielded pair from distributor to ignition box.

There is a chance that the box has something wrong internally. I don't think there are any tests you can run unless you have an oscilloscope. You'd also need a signal source to drive the ignition box.

As this seems to be an rpm-related thing, have you tried setting it at different speeds and seeing what happened?

Good Luck!
R.

I have checked all the spark plugs, they are good.
Pick up coil tests good, plug wires test good but they are a couple years old. 2-3 years old.
The leads that run to the pick up coil are a twisted pair that came with the ignition box.
And I added a twisted pair from a factory wiring harness off an older 72-74 w100 pick up to get a little more length out of them.
I have routed the pick up coil wires away from the other wires as best as I could.
The ground behind the seat of the truck probly isn't the best ground for the ignition box, but I have a heavy ground going from engine block to negative battery and from under hood on radiator core support to engine block and a heavy ground from frame to inner fender under the hood.
I posted a thread exposing this issue with the crane box on another web site and a guy said he had a problem vet similiar to mine with the same ignition box and coil and it ended up being the coil, and that he sent it back to crane and they sent it back to him claiming it was fixed and it did fine for awhile and then the issue came back.
He said when it came back he ditched that coil and bought an msd coil and it's been good ever since.

So here is a little update, I ran a 10 gauge ground wire directly from the negative battery terminal to the ground wire on the crane ignition box and it didn't solve anything.

Sorry you are still having problems.

Chrysler dealerships used to have a special "black box" that could ride in the vehicle and record the frequency and amplitude of a shake, which is very valuable in narrowing the source down to wheel, diff, u joint, shaft, trans, engine, etc.

If it were my vehicle I would next do a
"Percent Power Drop" test at 2500 rpm
on each of the eight cylinders
by shorting each cylinder's spark plug in turn and
recording the rpm drop
to see if the miss is one one cylinder all the time,
or a wandering ignition problem that affects all 8 at random.

If its a wandering miss, substitute in known good ignition pieces one at a time.

If you find a bad cylinder, swap known good ignition pieces in one at a time, and carefully examine the distributor electrical path for that cylinder.

If the ignition pieces swap have no effect,
do a 'Dynamic compression test' and then a
'cylinder percent leakage ' test.

An ignition oscilloscope that shows all 8 cylinders "traces" on the screen can be very helpful.
More modern diagnostic scopes can also record 8 cylinder instantaneous pressures and temperatures picked up from special washers under spark plugs.

This probably is not the problem because I've only seen it once. But I had a BB with a miss at about 2500 rpm that turned out to be a gide and spring issue. We replaced the springs and did a valve job on the new Edelbrock heads. Problems solved.
This was shortly after the heads came out.

I'm thinking about just buying a cheap 12 volt coil from one of the part stores and throwing it on just to see if it is my crane cams coil that's causing this.
Is there any particular coil I'd need to get in order to test it out? Or would any 12 volt coil suffice in a quick little test like that.
Wouldn't run it very long, just long enough to fire it up and bring it up to 2500 rpm where the Miss firing fit comes on at.
I have done a warm compression test on this engine and every cylinder is dead on at 150 psi.
I can do another one if need be but it was only like 7-8k miles ago that I did a compression test on it.
Maybe even only 5k miles ago.

A special meter is useful to track down ignition faults.

I now have two of these Actron KAL Equip 2969 three way ignition testers

http://www.ebay.com/itm/Kal-Equip-Spark-...509&vxp=mtr

I bought the first one used for about $60
and after using it a few times decided that
a second one to compare two cylinders simultaneously,
or to compare an all cylinders average to one suspect cylinder would be helpful.
The second cost about $40.

These give you:
peak Kilo Volts to initiate the spark,
average milliseconds of spark duration also called "burn time"
and the lower "burn" level KV after the spark starts
If you hook the pickup clamp around the coil wire it gives you the average of all 8 cylinders.

The length of burn time gives a hint about the air fuel ratio mixture in the cylinder.
I believe this A/F ratio effect can be compared more dependably if you swap in the same special long ignition wire and iridium tip spark plug to the cylinder you are measuring.

I would rather own one of the Sun Machines
with the big 8 cylinder at once screen
like I had in the 1980s
but these KAL Equip units are a cheaper and more portable alternative.

You want an E core coil. They are under the hood in a number of Ford products that used the TFI system. There is one on Ebay right now that's US made and ships for $9.32. But an 84 - 97 Taurus or Mustang or most whatever Ford will have one. The FD478 is the $9.32 coil.

R.

Do you have a stock ign (& coil) that you can toss in for a test?

You need to determine whether your issue is related to one or two cylinders or if all of them are struggling. Have you used the timing light to diagnose the problem yet? Its very easy to do.
This will get expensive (and frustrating) for you if you just start shotgunning parts at it.

^^^ Excellent! he did try the light & it was showing a miss but not sure what wire he had it on & agreed I would do all 8 EDIT If there is an open at the plug (not likely/I cant see how) or its plug wire (very possible) there would be no flash (no ground path) & if the plug is fouled to the point where there was no spark cuz the current dead shorted in the carbon to ground thru the plug base it would flash but the cyl would not fire. We need closure here!

Just wondering, wouldn't it make sense to pull and clean the plugs to address this issue?

Screw driver inserted in plug wire and held near ground to see spark?
Am I missing something?

Back in "the day"

I have had spark plugs fire until compression came up... Hard way to find a bad plug...

So I figured out the issue, it was a combination of old plug wires and Rotor phasing issue.
I bought a new coil, a crane cams ps92, installed it, and the issue was still there at 2500 rpm.
After that I installed the new spark plug wires that I bought, and tried it and the problem was a lot better.
Then I decided to try un-plugging the vacuum advance and it's gone compeltely.
So now I know this is a rotor phasing issue on my brand new firecore 50 distributor.
Not exactly sure how to correct this problem.
I hooked my mitt vac pump up to the vacuum advance, and applied vacuum untill the arm was fully pulled back, and I checked the gap at the reluctor teeth and the pick up coil post and all 8 of the teeth were exactly .008.
So Im 90 percent sure this is a rotor phasing issue when the vaccum advance is applied.

take off the cap & check that the rotor is retracted all the way (it should be from the springs unless the slots/pins are gummed up). loosen the holddown clamp & turn the dist housing slightly a bit till the magnet is dead even with the closest reluctor tooth. tighten the clamp.
Make a magic marker mark on the side of the dist housing straight down vertical/plumb from the rotor tip clocking. replace the cap & make another magic marker mark on the dist housing side inline with the "bulge" of the particular cap terminal where the rotor is located at which will be pretty close to your first mark. You want the rotor at rest to be pretty much clocked right at the cap terminal bulge center & the can will shift RP CCW on a SB so ideally you want the rotor to be a bit CW from dead centered. edge to edge in a vertical plumb CL is good. You do have some leeway there cuz the cap terminal is .214" wide and the rotor terminal is .244" and the can shifts the rotor .023" around its travel arc for every degree stamped on the can. also check the rotor tip to cap terminal clearance, ideal is to reduce it to .015" by drilling out the rivet & makeing your own blade. On OE dists, the reluctor gap opens up as the can adds advance so if your dist does not then that is a bennie. Are you sure yours is staying at the same .008"?

Yes I'm positive, before installing this firecore distributor I removed the cap and
Checked all 8 reluctor blades to pick up coil post clearneces with a brass feeler gauge, all of them were at .008.
I then hooked up my brand new mity vac hand pump to the vacuum advance and deployed the vacuum advance untill the arm was fully pulled out and I held it there with the mity vac while I went around each tooth on the reluctor and again they were all at .008.
The rotor that came with this firecore distributor already has a longer blade then the factory rotor blade.
I was thinking about buying a cheap distributor cap and drilling a hole
In it by the number 1 plug tower and then hooking my timing light up to it and watching it at 2500 with the vacuum advance plugged in and then I can get an idea of how far off the phasing is.
Then I suppose I could ether buy the reluctor that Rick ehnberg sells that has multiple key ways cut into it for rotor phasing, or I can buy another cap and modify a new slot on the base of it to put it on the distributor.
Or I could send it back to firecore and make it their problem to fix it cause it's still under its warranty.

Another option is I can pull the distributor and change the mechanical advance to increase the timing a little more and then I can back off the vacuum advance a few degrees and see if that's enough to correct the issue.

You might call Firecore ask them about returning it. Yes you can drill a 1/2" hole in the top cap flat 2/3 of the way from the center cap terminal over to the #1 cap terminal to shine your light into to check RP. You can redrill your reluctor yourself: drill a bit inward from the ID then use a mini round rat tail file to open it up/break thru to the ID. carefull measureing & if you are too far off there is plenty of area to drill several of em. First try the BB OE roll pin hole. here is one in progress. EDIT I gotta figure out how to work this camera.

The issue appears to be solved, I increased the initial timing from 16 to 18 which made my total go from 32 to 34, I then dialed back the vacuum advance to add 12 degrees of timing to the 18 at idle for a total of 30 at idle.
I had to turn the screw inside he vaccum canister about 4-5 turns outward to get it to drop the timing 2 degrees.
I think the vacuum can was wide open on this distributor and it was just advancing it too far and throwing the phase off.
I haven't driven it a whole lot since dialing back the vacuum advance but the little drive I did go on tonight I took it up to 3000 rpm in 2nd gear and held it there for awhile waiting
To feel the miss fire and never did.
So it appears to be solved, but I will drive it more in the next couple of days and report back if I find any Miss fires through out the rpm range.

That is real good to hear (& didn't take alot of digging in which wouldn't have been fun).

So now I am left pondering about
"Drilling out the rivet and making your own rotor contact"

On a Magnum style V8
with slotted flywheel and crank position sensor triggering,
if you wanted to custom retard cylinder number 7 a bit,
could you custom make a rotor with wider tip
And grind away part of number 7 cylinders distributor cap post?

to do that you would need to change WHEN it gets triggered. A larger gap might only delay the flame arrival by half a nano second, not near enough for what you are wanting to do & if the available voltage is greater than the required voltage to jump a certain gap then all is good there as it will fire but a minimal gap is needed at WOT as cyl psi is higher & coil rise time available is less and sparks blacken the brass contacts & any spark outside of the combustion chamber is wasted energy & kudos to you on doing this, Smokey Yunicks take was to individually dial in each cyls timing/CR for max power, treating each cyl as an individual powerplant. Tho for our apps octane would be the limiter on the DCR.

So as promised I'm back to give an update.
I drove the truck around a little more today and was able to test it out better with more open road and a longer drive.
I can still feel a very slight miss fire type vibration that comes on around the same time as before 2500-2600 rpm, but it is about 80 percent better for sure.
So my question is does mechanical advance affect rotor phasing? Or is it only vacuum advance that affects it?
And my next question, is there anything else I can do before modifying a distributor cap that lines up better with the rotor blade?
I was told I could file down the edge of the rotor a little bit the side where it spins under the contacts to help give the spark a little smoother transistion to the cap terminals.
Thinking about trying that.
Im also considering calling firecore and explaining the issue and seeing if they are willing to fix it.

Only vac advance affects Rotor Phasing, mech adv or initial timing does not. I would highly suggest modding the reluctor as opposed to altering the cap which will cause problems as that (2 side clips etc) is a flimsy system). I would just drill another roll pin hole in the reluctor & you're all set on RP then if that ain't it then we can continue on. How far is the RP off now?

I'm not sure how far off it is, I haven't had a chance to buy a cheaper cap and drill a hole in it to watch it, but I know that's what this issue is, because when I un-plug the vacuum advance it's completely gone, and like I said turning the vacuum advance down some made it a lot better but with the vacuum advance turned down a little and hooked up I can still feel it going on but it's not as severe.
I wonder if the guy at firecore has a distributor machine? I'm thinking about calling them and explaining what's going and what rpm and what the vacuum is so that maybe they could mimics the situation on a distributor machine and watch the rotor and then know exactly where it needs to be.
I guess I could do the same thing with a different reluctor, I just don't want to void my year long warrajtynon the distributor by modifying it or parts on it in case I run into other issues with it later on.

Oh OK I see what you are sayin, you don't want to void the warranty. Yes call em & go from there. post what they have to say. I would drill another hole in a cap as that is likely what they might ask, is how far off is it? EDIT You wouldn't want to send it in just to find out what you can find out yourself (how far RP is off). One other thing I would do now is bump up the timing/RPM to where it was acting up before (with the can capped) to see if it strickly a RP issue & not timing. You would need a dialback.

I have a digital dial back light with rpm read out.
I have capped the vacuum advance brought the rpm up to 2500 while
In nuetral and didn't hear it Miss firing.
And I've also capped the vacuum advance and drive it and don't feel it anymore.
I'm going to call them this afternoon and see what they say, is gonna ask for permission to fix it myself without housing the warranty if they say that's ok I'll modify my own reluctor is they say no I'll ask them to modify the reluctor

if it missed at 2500 steady RPM with the can hooked up then you might run it up to 2500 with the can capped then bump up the timing however much the can added (a 13 dist plate adds 26 degrees) & see how it acts & they will likely be asking for a timing number when you call.

Oh I see what your saying, advance the distributor to where it's at the same amount of timing as it is with the vacuum advance hooked up at 2500 rpm to see if it's still there.
That makes sense, my mechanical advance is set at 16 degrees, initial is at 18 degrees which makes the total at 34 degrees.
Vaccum advance is adding around 12-14 degrees at 2500 rpm, so that would be around 46-48 degrees of timing.
So I can increase the initial timing to 30 degrees on the distributor and leave the vaccum advance capped off and that would put my total timing around 46 degrees.
Is that going to be safe to do while holding the throttle steady at 2500? I don't see why it wouldn't be since the vaccum advance puts it around the mark anyway.
I will double check what the vacuum advance is adding at 2500 and then increase the distributor timing only to mimicking the same timing events to rule out any other issues other then rotor phasing.

Now since vacuum advance is the only thing that affects rotor phasing, I can also pull the distributor from the engine, throw on a different cap with a hole drilled by the number one cap terminal, apply my mity vac to the vacuum advance and then turn the distributor by hand to watch how far off it is from the cap terminal too correct?
This seems easier then trying to be over the top of my engine while it's revved up to 2500 trying to look down a little hole with the timing light.

You'd be surprised how inaccurate many of these are, esp the cheaper units, they'll have you chasing a "ghost" when it's the gun all along....

IMHO, buy yourself a basic/standard quality timing gun, or at least one to confirm the results/settings with your dial back

I've compared my light to two other lights and it's always the same, and I know my balancer is correct, I've verified it with a piston stop.
My light wasn't a cheap piece of crap ether.
I have the digital dial back light and then a regular dial back light, they are within a degree of each other, the older light will read a degree lower then the new digital light.
Another question for rapidrobert, what size drill bit will I need to add new slot to the reluctor? And will my idea work? Can I pull the distributor and apply the mity vac to it and then spin the distributor by hand to see how far off the rotor is from the cap terminals?
,

for a static (non rotating) test you could line up the magnet to a tooth. install cap. make a mark on dist metal side below the CL of the dist cap bulge (just below the bottom rim of the cap). take off the cap & see how far the rotor clocking from that mark then pump it up & see how far the rotor is from the cap bulge CL. make sure the springs are retracted & this test is "close" cuz the ign fires when the tooth is "just" moveing away from the magnet & it is hard to dead on visualize that timing (make sure the tooth stays dead even with the magnet, putting the lower tang in a vise works good). (best way) you check it running with your cap with the 1/2 hole in it, at idle with the can vac nipple capped then with it still idling pump up the can with the mityvac & see how far it moves as you have the light on it, (dont forget to have the DB back to zero), no need to do it at 2500. If it wont run with that much timing then rotate the dist back. Since RP ain't RPM/initial timing/mechanical timing dependent you don't need to have it at 2500 to check. On the 2500 RPM timing check if it was misfiring with the can hooked up at a total of say 46 degrees then run it up to 2500 then unplug the can/cap the nipple & turn the dist till you have 46 deg & see what develops. IIRC you turned the can innards with the 3/32 allen wrench & it got better but if the vac amt at the can is above what it takes to max it out at then the RP change is gonna be the same, it just that CCW with the allen wrench makes it take more in hg to max out at so check on that & you have a huge advantage haveing a Mityvac to play with. I don't remember offhand what size drill bit it takes but at least on an OE reluctor you can look down at the unused roll pin hole to fit a drill bit to it to get the size needed.

Good point it doesn't need to be at 2500 rpm to watch the rotor phase being only dependent on the vacuum advance.
I will get started on this first thing Saturday morning and hopefully have myself an engine that's miss fire free before the weekend is over.
I see that Rick sells a modified reluctor online but he charges 35 bucks for it, seems a little pricey and I shouldn't have much of an issue making my own dowel pin slot on the reluctor with my drill and vice.
The miss firing got better when I turned the vaccum advance ccw which turns it down I thought? Or makes it require more vacuum to advance it.
So I'm thinking the rotor phase is too far ahead which is in turn cross firing to the cylinder ahead of the cylinder it's supposed to be firing, which makes me think I'm going to have to bring the reluctor back a little bit.
I still don't fully understand how this re-locating the reluctor changes the position of the rotor but I'm sure I'll figure it out. Does changing where the reluctor is mounted change where the distributor shaft is lined up?

first we gotta find if the phasing is too far in front of or too far past the cap terminal. Ideally you want the rotor at or near the trailing (far) side of the cap terminal when it fires as RP will pull it back the other way (against rotation). If Ricks reluctor has the multiple roll pins holes & I believe it does then it simplifies things as one of those holes is for sure gonna make the RP line up but there is plenty of material there for the same # of holes for us to drill to get it right, just takes time & some carefull eyeballing/measureing then drilling. On the timing, Say a can offers 22 (crank) degrees, going CCW makes the can require more vaccum for the can to start offering its advance amt from zero/& a higher vac # for the slope to max out at its max 22 degrees of added advance. If going CCW, the slope (amt of advance) is the same, just starts later/maxes out later (later being a higher in hg #) EDIT so I was wondering if the can was fully deployed (max vac) the 2nd time when it missed less after turning it CCW cuz if it was then RP arc distance would have been maxed out in both cases (to further pin down if too much timing is a factor).

Gotcha, I'm gonna start on it tonight after work. I'll modify a cap with a hole and watch the rotor with the vacuum advance connected.
Then I'll bring distributor timing only up to 46-48 to 2500 and see if the issue is still there.
Cause that's about where it is with vacuum advance hooked up

yes, freeze the rotor with the light while idling with the can hooked and unhooked & see how far the rotor swings between the two. then at 2500 with the can plugged in, get the timing where it was when it was missing, then unplug the can/cap the carb nipple & twist the dist to get the timing back to the same #/same 2500 RPM & see if it misses or not.

I'm getting started on this this morning.
I did some reading on rotor phasing on the small block distributors last night, and it's said that since the small block distributors spin clockwise you should always start with a slot
That's machined after a reluctor tip. Ether 5-10-15 degrees after a reluctor tip.
I'll report back soon with my findings.

Ok rapid Robert, I got a hole drilled in an old cap and put it on and checked the rotor phase with and without the vacuum advance and the rotor phase is off with and without the vacuum advance, it's not as far off without the vacuum advance but it's still not directly under the cap tower.
I took a black marker and marked where the cap terminal is and where the rotor is with just mechanical advance no vacuum advance and where the rotor is with vacuum advance.
The rotor is behind, it needs to come forward more to be under the cap terminal.
I took a picture of the cap with the marked locations of where the rotor is.
But I can't figure out how to post the picture on this page.
Idk what a URL is and how to get one.

Here is the photo of the distributor cap marked with where the rotor position is.furthest to the left is where the cap terminal is, the mark in the middle is where the rotor is with just mechanical advance, the mark furthest to the right is where the rotor is with vacuum advance.

Do I have to make a new hole in the reluctor for the roll pin a little ahead of the original hole or a little behind the original hole to get the rotor to come forward more?

looking down at the reluctor, make a new hole maybe 10 deg CCW from the orig hole. cap bulge to cap bulge is 45 deg so from your sharpie marks it might even take 15.

Thank god you replied!!! I've been wanting to hear which way to try a new locating hole, so my next question is how do I measure in degrees to get the spot at least some what close?
How far apart is each tooth on the reluctor roughly? That would give me a good starting point on how far it needs to be.
I'm going to the hardware store with my digital micrometer to measure out different sized drill bits to use on making a new hole and I bought 2 other reluctors to have as spares in case I botch one of them

each tooth on the reluctor is 45 deg apart the same as it is on the cap bulges (just around a smaller dia circle). Here's a pic with all of em drilled (I ain't mini rattail filed out to the ID yet on all of em). The OE (2) holes are very close to 6/12 as I have it clocked in the pic. EDIT After more eyeballing & I might be turned around on the CCW, it might be CW.

So your thinking I need to do a new hole 15 degrees clockwise from the original
Hole?
I read on Rick ehrenbergs instructions with his multi indexed reluctor that on small
Block distributors that rotate clockwise you want to use a slot that's behind a tooth.
Wether that is clockwise or counterclockwise to the original slot I'm not sure?
Also what is a mini rattail and where would I find some? Are they are the hardware stores?

What size drill bit for a 6/12 hole?

the mini files usually come in a pkg with a bunch of em (half round half flat full round etc) & the one you wantin the pkg is round/tapered like a rats tail. I'd say do some carefull visual on the arc distance & actually there is plenty of material to drill several holes in each one like Eberg did on his. The goal is to have the rotor/cap interface, the rotor at the trailing (CW) edge of the cap terminal as the RP change from the can will swing it back CCW on a SB. I cant say for sure on the 15 deg, just visual and measure & it may take several holes to get it dead on. Keep in mind the rotor terminal is .244" wide & the cap terminal width is .214" so you have some leeway. the goal is to get that distance as close as possible including radial rotor tip to cap clearance (lengthening the rotor blade might be needed also) in addition to the around the circumference distance we are working with right now. EDIT the holes at 6 & 12 o'clock are the OE holes & the top one looks like a square but that is camera distorsion & it is round like the 6 o'clock one. MORE EDIT I would take the reluctor with you to the hardware store & get a drill bit to match the current holes as that is the roll pin size you will be (re)using.

Based off the measurements of the roll pin that holds the reluctor to the shaft I got a 3/32 drill bit, I will need to get a rat tail file in the morning.
So I am still confused as to wether or not I need to go clockwise to the original hole or counter clockwise to the original hole?
I'm going to get it started on it all first thing in the morning.
I already have a rotor that has a longer tip on it, the firecore distributors come with a rotor that has a longer blade then stock on it.
So I have the drill bit I need and the drill and a vice I will get a rat tail file in the morning, I just need to know if I'm drilling a hole cw to the original hole or ccw.

CW as best as I can visualize (been awhile since I last done it & my note takeing is terrible) & the reluctor rollpin hole is .098" so yes a 3/32 drill bit will work fine. Just be sure to drill outward a bit from the center hole ID & the circular "flat" you are working with is about 5/32" wide so start in the center. A pin punch to start a depression for the bit to start & not wander helps too. You're also on CDT & it is 8AM here so hopefully I caught you in time.

Yes I just got the distributor pulled and the reluctor pulled and in the vice and marked where I'm going to drill a new hole.
I'm going cw from original hole and hoping that's what will move the rotor forward lol cause I have no idea.

If worst comes to worst, you can always drill another hole in the opposite direction and call it good. I'll never tell.

Already done for you

So to dial this in, you would adjust reluctor to be firing Dead center at normal cruise speed with vacuum?

Say 2500-3000 RPM?

Ya but at 35 dollars and waiting a week for the shipping to get from New York to Montana where I am.
I'd rather spend the 10 bucks on a couple of reluctors and drill a new hole myself.

You can see the original hole and where I am going to put a new hole about 15-20 degrees cw of the original hole.

Made the new hole for the roll pin and filed it out and it fit perfectly and ended up fitting real nice on the shaft, I really hope cw was the right direction to go inn cause of how perfect this turned out.
I'm installing the distributor back into the engine now and I'll report back with the findings after I hook up the timing light and watch the rotor.

So going cw from the original hole made it worse, I think that's the wrong way, cause it instantly started backfiring out the exhaust and wasn't happy about running.
So now I'm pulling it back out and am going to make a new hole ccw from the original hole.

Ccw from the original hole is correct, I got my timing set and now I'm throwing some pants on to lean over the engine and watch the rotor. I watch the rotor with just mechanical timing set at 16 degrees and the rotor was slightly ahead of the cap terminal so with vacuum advance hooked up it should pull it back directly under the cap terminal.

So the hole I did moved the rotor forward that's for sure, but I think I did it a little to far forward,
So with one of the reluctors I bought I'm going to do a new hole a little closer to the original hole and try it again.
It sounds smother while idling, but I brought it up to around 2500 rpm and it was still Miss firing but it wasn't as severe as it was before relocating the reluctor.
So I think I'm a little too far forwards
I think I moved the rotor forward about half which would be 22.5 degrees and I think the sweet spot is gonna end up being 15 degrees like rapid Robert had guessed.

Here is a picture with the rotor frozen with the timing light on it, this is with 16 degrees of initial timing and 32 degrees total timing with another 14 degrees of vacuum advance at idle for a total of 30 degrees of idle timing.
The hole in the cap is cut right above the number 1 cylinders plug on the cap, you can see that by making a new spot on the reluctor ccw from the rotor that I moved the rotor forward, but it is a little too far forward which you can see in the picture that it's a little past the cap terminal, which is why I still have a slight missfire but it is much better then it was before I relocated the position of the rotor.
I'm drilling a new hole on a new reluctor ccw that's a little closer to the original hole and I'm hoping that will line up it perfectly, just by eye balling I'd say I'm gonna pull the rotor back another 5-7 degrees and I'm hoping that's all that's needed t have it perfectly phased.

I would redrill another hole in the same reluctor, just go to another 45 deg space inbetween another set of teeth. EDIT with a 45 deg spacing on the C to C of a pair of cap bulges, an 11 deg can will swing an arc 1/4 of that distance. Ideally you want the rotor tip to cap terminal tip gap to be the closest at WOT (no/mimimal vac) as the can is retracted & the required voltage to jump the plug gap is the greatest at that point in time (high cyl psi) and the available voltage is the lowest (coil rise time between firings is the lowest at that fast rising/higher RPM) & it takes energy to jump that meaningless gap then what is left goes to the plug.

Ya I didn't even think about that! O well I have 3 brand new reluctors to work with.
And I can order more if need be.
Im getting ready to try the reluctor that's slightly closer to the tooth, and I'll report back.
Judging by where the rotor was with my last reluctor position I'd say it needed to come back another 7-10 degrees cause I think the first hole I made ccw from the original hole was about 20 degrees away from the original.
So I made a new one on one of the new reluctors that's about 15 degrees away from original hole roughly.

just (3)

So that distributor sent me to bed tonight feeling totally defeated, I feel like I got my ass kicked by that thing.
I gave up, I tried a hole behind the original hole on the reluctor I bought at the parts store and it wasn't happy with it because of some of the teeth being longer then some of the others I think the reluctor teeth were smacking on the pick up coil post.
Not 100 percent sure, I just heard it making a strange noise around the distributor that changed tone with the timing.
So I grabbed the original reluctor that came on the firecore distributor, picked a different tooth that hadn't had any drilling done on it yet, went about 15 degrees ccw from the tooth.
Put it back on dropped the distributor back in the truck and started it and it's running rough as hell hardly wanting to idle, i shut it off and slammed the hood and said [censored] you im done.
So first thing tomorrow morning Rick ehnerberg is getting 35 dollars of my hard earned money for one of his reluctors and I'll have my fingers crossed that it works.
The closest I can this weekend to having the rotor properly phased was when I shared the photo of it being a little too far forward from the cap terminal, after that it all went to [censored] and I started having problems drilling straight holes into the reluctors and having problems getting the roll pins to go in the slots that I drilled, hearing strange noises from the distributor with the part store reluctor and then having the truck not even wanting to idle after a long a new hole.
It was just a total ass bearing with that truck winning by knock out in the first couple rounds.

So last night when I decided to give up on phasing the rotor, I pulled the distributor back out and brought it inside and was fiddling around with it and I noticed something odd that I'm wondering if it could be causing the rotor phasing issue.
When I hold the shaft at the bottom of the distributor (the part that goes down into the engine) and then I hold the shaft at the top (where the rotor goes on) the top part of the shaft will rotate clockwise a good amount while the bottom half of the shaft isn't moving at all???
It's like the top part of the shaft is spring loaded and it will twist back and forth while the bottom half of the shaft is staying solid.
Is that normal?

You're probably just seeing how the mechanical advance springs work.

Ok that makes sense, it just made me wonder if when the bottom half of the shaft is spinning by the engine if the top part is lagging or going faster then the bottom half which in turn could be causing the rotor phasing issue.
Maybe I should call firecore and ask if that's normal

One other issue I was having is whenever I relocated the reluctor I would have to physically advance the distributor a lot further over to achieve the same amount of initial timing which makes it impossible to plug in the vacuum advance.
How do I get the correct spot back on the distributor housing without affecting the timing? Do I have to pull the oil pump drive thingy out and re-locate it and then drop the distributor back in pointing the rotor where it needs to be?

Yes reclock the intergear. stick a large screwdriver in the slot & twist it CW & see if it will rise up & over the teeth (1) notch then let it fall back down. If it is real tight you may need to use two thin stiff pieces of wire with an L bend on the ends to get it up off of its seat. things are tight in that area.

Ok I ordered ricks modified reluctor this morning, my drill bit started to get dull after a couple holes drilled into the reluctors I had and it got harder to drill a straight hole
That the roll pin would fit snug into, I don't have a drill press or even a shop
I was doing all of this in my driveway with a hand drill and vice, it was just pissing me off to the point of saying screw this, I had it some what close that one time but the rotor was a little too far forward after re-positioning the reuctor ccw about 20 degrees.
Ricks reluctor had holes drilled and is noted how many degrees, I'm thinking 10-15 degrees ccw and it would be pretty much spot on.
The slop that I'm feeing at the top of the shaft on the distributor is that just the advance springs? And is it normal?

its a combo of the intergear notch/dist lower shaft tang rotational slop and or the springs. if you are not twisting hard enough to get into the springs then it is all intergear slop. it does cause spark scatter at idle when timing it (spark jumping) & it it indicative of a less than a spot on perfect eng but might be left alone as is for now. People have reportedly resolved it with a 1/2" ID setscrew collar slipped on the shaft but I would rather have my welder build up the tang for a dead on rotational rather than the axial solution with the collar fit & seperately, further up, adding shims above the plastic collar with the roll pin to reduce the lower shaft axial play to .005". speedway mtrs has a kit of dead flat thin shims for $10.

So how do I determine if it is all advance springs?
Just watch the springs as I get the top part of the shaft to move? Cause if it's slop in the distributor then I'm returning it cause that would be bs this thing doesn't even have 100 miles on it.

I called firecore and talked to a guy in their tech department and he said that movement on the top part of the shaft where the rotor goes is from the advance springs and mechanism.

with the dist installed of course, if you barely twist the rotor back & forth, not enough to be stretching the springs at all (& the spring tension is there only when twisting in one direction, CW on a SB), then any slop is in the lower tang. Most dists have "some" but you do want it as close to zero as possible.

Yes I'm mimicking an installed situation by grabbing the bottom half of the distributor shaft with my hand and holding it steady, same as it would be installed in the engine, and then grabbing the top part of the shaft where the rotor goes and twisting it I can get it to move a little bit and it would retract just like it was spring loaded.
So it makes sense that it is the advance mechanism and springs causing that.

actually the intergear/dist has to be installed to see how much slop there is between notch/tang when those 2 parts are interfaceing each other. But we should be good once we get the RP taken care of & hopefully the missing taken care of.

I sure hope so, if not I'll just return it, the one nice thing about the firecore distributors is they come with a 1 year warranty.
And I already talked to firecore about some of the issues I've had with rotor phasing and the guy said he'd never heard of that before which struck me kind of odd.
You make mopar distributors and have never heard of rotor phasing issues? How is that even possible?
When I described the movement he knew right away what I was talking about and was adiment that was the advance springs and mechanism.
It's installed right now so I can pop the cap and see how much movement is there.
I want to pull it tonight anyway to get the oil drive gear over a tooth to keep the distributor in the place that it needs to be.
Because right now whenever I modify a new position on the reluctor I have to physically advance the distributor so far to get the same amount of initial timing that the vacuum advance is behind the intake manifold and there would be no way to get the hose on the vacuum can and no way to adjust the vacuum can.
Ricks modified reluctor will be here Thursday.
And I'm hoping that's the answer to this issue, the Miss firing did seem to get better when I had the rotor a little too far ahead of the contact which is when I took that picture and posted it but it was still missing a little bit, not as severe as before however.
The two positions I've been able to try are ether too far behind the terminal that it should be under or a little too far ahead of the terminal it should be firing.
Msd makes a distributor that has an adjustable rotor for rotor phasing but it doesn't have vacuum advance.
Us mopar guys are very limited on distributor choices and it sucks,
Gm guys are spoiled with how many different hei units there are out there plus they get that giant cap and rotor which makes it easier to phase a rotor and makes it to where rotor phasing isn't as critical with such a big cap with terminals so far apart.

So to get the vacuum advance on the distributor to stay pointing at the passenger side fender of the truck do I have to rotate the oil drive gear over a tooth going clockwise or counter clockwise?
Every time I've installed the reluctor ccw on the distributor it requires me to turn the distributor so far ccw that it's pushing the vacuum advance into the back of the intake manifold.

CW, EDIT don't forget to reclock the plug wires, I got bit by that the other day.

Re-lock the plug wires, you mean a jen sure they are pushed down in the distributor cap?

No, just confirm that the #1 plug wire is above the rotor

Oh so I'm going to have to go through the whole process of removing a spark plug and making sure the engine is at tdc on the compression stroke and then placing the rotor under the number 1 plug wire to reposition the distributor once I move the drive gear over a tooth?
I was thinking I could just mark where the rotor is right now and pull the distributor and then move the oil drive gear over a tooth and then put the distributor back in with the rotor pointing wherenitnwas prior to removing the distributor.

yes that would work with carefull positioning, you are just lifting the whole shebang (intergear/dist) up & shifting (rotating) everything an intergear tooth CW then setting it back down into place. EDIT the crank (dampener) ain't being moved the cam ain't being moved so now when done repositioning, if the magnet is dead even with the tooth then it is firing at the exact same point in time that it was before and if our phasing is now good then we're good.

I've decided to just wait untill I have the rotor phased correctly before moving the oil pump drive gear to re-position the distributor.
I should have ricks modified reluctor tomorrow and I'll take another stab at it this weekend.
Based on how far forward unmoved the rotor when modifying my own hole about 15-20 degrees behind the original I'm thinking I'll try the 10 degree hole on ricks reluctor first.
And I'm also thinking with the reluctor installed 10 degrees behind the tooth it shouldn't require me to move the distributor forward much more then it already is originally
Located which would be nice cause then I don't have to re-position the distributor.
If I end up having too then I will, but I'm going to try getting away with not having to at first.

agreed, lets get the phasing corrected then we can get the vac can on the pass side clocked to where is has room to be moved back & forth a bit to set the initial & ideally you would like the #1 plug wire location in the cap to be facing forward toward the front of the car & a bit toward the pass side (on a SB) & lifting/reclocking the intergear locates this. this lets the plug wires nestle the neatest & be the shortest lengths possible. Not a dealbreaker by any means but something to keep in mind.

Well I got ricks modified reluctor installed this afternoon in the 15 degrees behind a tooth location, installed the distributor and fired it up and as I was trying to watch the rotor with the timing light I was hearing a strange noise coming from inside the distributor.
So I pulled it back out and took the cap off and knew inidiatley what I was hearing because there was little tiny metal shavings sticking to the magnet on the pick up coil.
Mind you I set every tooth at .008 with a brass feeler gauge and applied my mity vac to the vacuum advance to insure all 8 teeth were at .008 with vacuum applied as well.
Which doesn't really matter cause I didn't have the vacuum advance hooked up while watching the rotor this afternoon.
Anyways the problems there is a lot of slop on the top part of the distributor shaft that the reluctor slides on and that the rotor sits on.
So because of the place it's forcing the reluctor to smack the pickup coil post.
I did my best to measure the amount of play and it's right around .006 to .008.
So while it's running that reluctor is just wondering all over the place because of it.
Rick from firecore had called me earlier this week cause I had called firecore to discuss some of the movement I was feeling on the top half shaft of the distributor and he said that was normal advance mechanism movement.
Which I know now is not the case, the reluctor should not be hitting the pick up coil post.
This distributor doesn't even have 100 miles of run time and I've just had nothing but problems with it from day one, rotor phasing off so bad it's Miss firing like crazy, movement at the upper half of the distributor shaft.
I attempted to call Rick from firecore back this evening and got his voice mail.
I left a message explaining I'm having some issues with one of his distributors and that id like to discuss them with him.
It has a 1 year warranty so I'm hoping he will send me another unit that has a tight upper shaft on the distributor and being in phase would also be nice, if not I can phase it myself with the modified reluctor from the other Rick guy.
Very frustrating though, my truck has been down for weeks now cause of this distributor.

this is side to side (radial) play, in other words with the gap set at .008" the shaft can move side to side enough so that the tooth are contacting the magnet? that side to side clearance (play) should be near zero.

Yes radial play.
It's been this way ever since I got the distributor from Mancini and I think it's been contributing to the Miss firing problem I've been having.
Every time I tried to describe the movement I was told it was the advance mechanism and springs, which the advance mechanism and springs do cause a movement when the distributor is installed and this radial play is completely different.
So I just wasn't doing a good enough job describing the movement but I I now know that it's radial play, and it's got to be cause of a bad bushing or bearing under the top half of the distributor shaft.