msd ignition woes

ok, don't know if this is the right thing to do, but i'm going to start a new thread.

here is the ignition setup:

chrysler electronic ignition, set up by FBO with 12 degrees advance.
msd blaster 2 coil.

with this setup, the engine made 712 hp at 6k on the dyno. the dyno had a 6A MSD ignition box setup already in place.

put the engine in the car with the same distributor and coil, and my 6AL analog box. at first, the thing seemed awesome, but that may have been me getting used to it. but soon i noticed what seemed like issues with the old analog box, so i decided it was time to get a new one.

got a new 6AL digital, and the engine would run for about 30 seconds, fall on it's face and die. fought MSD, they finally agreed to RMA the box. sent it to them, got it back, and it did the same thing. i went through every test they asked for, and they sent me a new box.

- put the new box in, set the rev limiter at 6200, and it did NOT display the symptoms of the earlier box.
- the engine would not rev above 5000. 5000 was a hard limit, even with no load, would not go above 5000.
- set the rev limiter to 6300, and the 5000 limit was gone.
- now found that the engine was missing badly above 5k, and simply would not go beyond 5700 or so, missing the whole time.

what we did:

- tried a different distributor
- tried a different coil
- isolated the wires to the distributor from the MSD box
- isolated the hot to the MSD box
- checked the voltage of every wire connected to the MSD box

no change.

put in a dual point distributor and a napa replacement coil, NOT running through the MSD box, car ran like a raped ape, revving freely all through the range, NO issues whatsoever.

every action listed below exhibits the same problem:

- put the old distributor and napa coil back in connected to the MSD box.
- put an entire new wiring harness, using every single wire new, in other words, not a single wire that is currently on the car.
- put a brand new MSD blaster coil on
- put a brand new MSD 6AL box on

once i put the new MSD box on, i set the rev limiter at 6200:

- the engine stopped at 5200, even with no load.
- changed the rev limiter to 6300, and the engine stopped at 5800 with no load.
- changed the rev limiter to 6500, and the engine will go to 6200 with no load
- under load displayed exactly the same symptoms, missing and breaking up and will not go above 5700 or so.

next step:

- putting the points distributor back in, and will connect to the MSD box

step after that:

- find and alternative to MSD.

ok, so notice that both brand new MSD boxes, with the rev limiter initially set at 6200, would not allow the engine to go beyond 5000 the first time, and 5200 the second time, and that a mere 100 rpm change allowed the engine to go almost 1000 rpm higher.

so,

- what the hell is going on here?
- what do i do next?

and more importantly:

- what is the alternative ignition system to MSD?

Posted By: mickm

Re: msd ignition woes - 12/16/13 01:26 AM

so, the latest.

i have a new box from MSD, and put it in with it set at 6300, and the same behavior. would not go about about 5700 or so. note this isn't the rev limit behavior, in that the rpm fluctuates a few hundred rpm, and it is missing badly.

moved the rev limit up to about 7300 or so, and it would go beyond 6k, just as before.

so i put resistor plugs in, (hats off to GTX MATT), and the missing was gone. it now stops normally at the rev limit, except that the limit seems to be 1000 rpm off. i had it set at 6300, and it was rev limiting at about 52-5300. upped the limit to 6500, and it climbed a bit, then 6800, and it climbed some more. set the rev limit at 7100, and it now seems to limit at 6100 on the tach consistently.

a while back i tested my tach against a sun tach/timing light, and my tach showed 2 or 300 lower than the sun tach, (i forget which), so i'm relatively sure that these numbers are close.

so. now it seems to run, but do i trust that the box will always hold the rev limit down at that limit, or will it let loose some time and let the engine spin to 7000+?

the resistor plugs seems to have solved the issue of it missing, but now i have the rev limiter issue.

i really don't know what else to do except leave it as it is or get the 6ALN box as i was advised to by the guy i talked to (see earlier post in this thread).

ideas, comments?

Posted By: lilcuda

Re: msd ignition woes - 12/16/13 02:30 AM

I'm coming to the party a little late, but I'll give you my input. I have a friend who is an electrical engineer. He worked for Dynatek ignition about 20 years ago. They started out just doing drag bike ignitions, but have since branched out. Anyway, their major competition was MSD. He told me that MSD rev limiters were very "rough"for lack of a better term. The RPM would vary on the limiter by 500 or more RPM. The Dynatek stuff would be more like 100 or so RPM on the limiter. He made me a one-off limiter for my Barracuda since they didn't make one for V8s back then.

They do now. Check it out here:

http://www.dynaonline.com/skins/products/accessories/Dyna_RPM_Limiters/

When it kicks in, it is very smooth and the car just falls on its face. I would look into one.

Lee

Posted By: mickm

Re: msd ignition woes - 12/16/13 03:23 AM

Quote:

I'm coming to the party a little late, but I'll give you my input. I have a friend who is an electrical engineer...

well, to fill you in quickly, i have had nothing but issues with the box since i got it, and i'm on my 4th box. i contacted someone who rebuilds and fixes MSD boxes (not associated with MSD), and after i got about 1 minute into my situation, he told me to stop everything, there is absolutely nothing wrong with my car, it's the box. the 6AL digital boxes, he said, are known to have these issues with the rev limiters.

i don't feel good trusting my engine to this, so i will probably either get one of these dynatek limiters or go for the 6ALN, which is what this guy recommended.

so far this seems to be limiting the rpm at exactly the same place each time, but i've only done a few trials. so it seems that MSD can get the limiter reasonably close, at least. but it seems there may be some completely off the wall scenario with my car, (which i haven't ruled out), as it's hard to believe that 4 boxes have all been bad, (although the first two were displaying completely different characteristics, and were entirely unusable).

Posted By: MR_P_BODY

Re: msd ignition woes - 12/16/13 03:57 AM

You may have hurt the rev chips you have been playing
with... try some that havent been in the box while
its been missing, all they are is a resistor

Posted By: mickm

Re: msd ignition woes - 12/16/13 05:43 AM

Quote:

You may have hurt the rev chips you have been playing
with... try some that havent been in the box while
its been missing, all they are is a resistor

in the digital 6, the chips are integrated into the box, and are proprietary.

you set the limit by two rotary dials on the outside of the box.

Posted By: MR_P_BODY

Re: msd ignition woes - 12/16/13 05:48 AM

Quote:

Quote:

You may have hurt the rev chips you have been playing
with... try some that havent been in the box while
its been missing, all they are is a resistor

in the digital 6, the chips are integrated into the box, and are proprietary.

you set the limit by two rotary dials on the outside of the box.

I forgot you have a digital

Posted By: NITROUSN

Re: msd ignition woes - 12/16/13 06:03 AM

Make sure your battery is fully charged and disconnect all the alternator wires and take it out and see what happens. You wont know until you try it.

Posted By: hvyweight

Re: msd ignition woes - 12/16/13 06:05 AM

i kinda read through the replies. Did you try to remove the tach out of the senario?
i have seen tachs cause these issues.

Mike

Posted By: mickm

Re: msd ignition woes - 12/16/13 07:03 AM

Quote:

i kinda read through the replies. Did you try to remove the tach out of the senario?
i have seen tachs cause these issues.

Mike

no, haven't disconnected the tach. someone else brought this up, but this seems like a bit of a conundrum. if i don't have a tach, how do i know where it is cutting out?

it seems, so far, that the resistor plugs may have solved the breaking up issue, but i still have the rev limiter issue.

Posted By: GTX MATT

Re: msd ignition woes - 12/16/13 09:01 PM

Not sure if you want to go this route, but Summit has the 6AL analog boxes on clearance for 170 (maybe leftover stock).

At least your miss is gone though

Posted By: mickm

Re: msd ignition woes - 12/16/13 09:07 PM

Quote:

Not sure if you want to go this route, but Summit has the 6AL analog boxes on clearance for 170 (maybe leftover stock).

At least your miss is gone though

got a link? i typed in "msd 6al" and only the digital stuff came up...

Posted By: GTX MATT

Re: msd ignition woes - 12/16/13 09:21 PM

Wow, I feel bad for having got your hopes up, I just looked and couldn't find them either, but I swear to you they had them right before Thanksgiving because I was thinking about picking one up after reading about your issues. I guess its too late now! They said "In stock" and ready to ship "today" also.

Sorryy!

Posted By: Al_Alguire

Re: msd ignition woes - 12/16/13 09:25 PM

I did not read all of this but will ask a simple question. have you tried a new coil? I have had two coils show similar issues at higher RPM, both from MSD.

Having said that here are some universal truths about MSD.

One, they have NEVER had a bad ignition box. Trust me I do not know of ANYONE who has ever sent one back and had them say it was an issue in the box

Two, Just because it is new does not mean it is GOOD. There is a difference. The digital boxes seem to have more issues than the old school ones.

Three, If you send in your old box they will send it back saying it checked fine but usually the issues you had will go away. Never understood this logic on their part but seems to be universally true. We have sen tthree back over the years with issues. All came back with no issue found and all worked great when they came back.

Fourth, They are very suseptible to RF interference. Factory tacks, electri water pumps, electric fans, alternator wiring or any other high current wiring will wreak havoc on MSD boxes.

Posted By: mickm

Re: msd ignition woes - 12/16/13 09:40 PM

Quote:

I did not read all of this but will ask a simple question. have you tried a new coil? I have had two coils show similar issues at higher RPM, both from MSD.

Having said that here are some universal truths about MSD.

One, they have NEVER had a bad ignition box. Trust me I do not know of ANYONE who has ever sent one back and had them say it was an issue in the box

Two, Just because it is new does not mean it is GOOD. There is a difference. The digital boxes seem to have more issues than the old school ones.

Three, If you send in your old box they will send it back saying it checked fine but usually the issues you had will go away. Never understood this logic on their part but seems to be universally true. We have sen tthree back over the years with issues. All came back with no issue found and all worked great when they came back.

Fourth, They are very suseptible to RF interference. Factory tacks, electri water pumps, electric fans, alternator wiring or any other high current wiring will wreak havoc on MSD boxes.

all of what you are saying here regarding dealing with them i have experienced. my first two boxes would run fine for about 60 seconds or so, then cough, stumble and die. fire it up again, and exactly the same behavior. nothing wrong with the box.

yes, i have tried 3 coils so far.

i have an analog box, and there were two symptoms: one was varying rpm at specific speeds, and the other was what seemed like a rev limiter issue. so i decided to go for a new box, having heard nothing about all these issues.

with the resistor plugs having seemingly solved the breaking up and missing issue, i'm going to put my old analog box back in and see what it does.

right now, it runs great, i'm just worried about that 7100 limit the box is set at now...

Posted By: BJS racing

Re: msd ignition woes - 12/16/13 11:42 PM

Quote:

One, they have NEVER had a bad ignition box. Trust me I do not know of ANYONE who has ever sent one back and had them say it was an issue in the box

Man I am not trying to

but some how I must be different. I sent one back for someone and was actually told that the box was bad. I knew it was. I tested it before I sent it back. I also know the guy that owned it killed it welding on his car with it hooked up. But that is the only one I have ever heard of being bad.

Posted By: mickm

Re: msd ignition woes - 12/17/13 12:30 AM

this is really a tough issue. i have a hard time believing that the problem is not specific to my setup, but the symptoms are just too weird.

if you look at the beginning of this post, i have done everything i (and everyone around me) can think of, except two things: 1) i haven't disconnected the tach, and 2) i haven't tried different plug wires. that doesn't mean i haven't missed something, but so far it is all i can think of.

in the end, the real issue i have is this. that box is not rocket science. when you look at what that box does compared to a smartphone, we are talking many orders of magnitude more complexity. in today's world of micro electronics and circuitry, that box is pretty damn simple. doesn't mean they haven't put a lot of research and testing into it to make it what it is, but again, comparatively, this is simple stuff.

that it should be so sensitive to all this stuff is really a travesty.

i have a friend who put a digital 6al on a new build, runs fine. more or less the same setup as mine: stockish 69 car, wired the same way, etc� so what is so different about my setup?

could be the wires or the tach, but who knows. again, the question is why is something so seemingly simple this difficult to diagnose and fix?

ok, off the soap box.

now just on to doing what i have to do to make this thing work.

Posted By: BJS racing

Re: msd ignition woes - 12/17/13 12:52 AM

What do you have the ground on the MSD hooked to? That has been one of the biggest problems I have run across. If you turn the rev limiter off does it give you any trouble? I have also had trouble when (with a stock dist.) if you wire it backwards giving timing issues. Are the pick up wires from the box (purple and green) running near plug wires or the coil wiring? On some of the MSD systems there is a purple and green and there is a blus and green. Does yours have both? If so make sure its hooked to the right ones! Ask me how I figured that one out!

Posted By: mickm

Re: msd ignition woes - 12/17/13 01:00 AM

Quote:

What do you have the ground on the MSD hooked to? That has been one of the biggest problems I have run across. If you turn the rev limiter off does it give you any trouble? I have also had trouble when (with a stock dist.) if you wire it backwards giving timing issues. Are the pick up wires from the box (purple and green) running near plug wires or the coil wiring? On some of the MSD systems there is a purple and green and there is a blus and green. Does yours have both? If so make sure its hooked to the right ones! Ask me how I figured that one out!

a short answer to your question is that we took an entirely new wiring harness, and eliminated every wire existing on the car that is involved in the ignition system. we connected the positive and negative straight to the battery, we ran all the wires way clear of every other wire on the car, and it didn't make any difference at all.

the purple and green are connected correctly, verified that many times.

if i set the rev limiter way high, then it runs fine, but i have no rev limiter.

so far, it seems that the missing and breaking up has been solved with resistor plugs. now i have the issue that the rev limiter is set at 7100 and it limits at 6100.

Posted By: WadeMetzinger

Re: msd ignition woes - 12/17/13 06:38 AM

Have you tried what I suggested?

Quote:

There are many having ignition issues with the digital ignition boxes and from what I'm hearing they are caused from bad ground and the solution is pretty simple run a wire from the back of one head to the other and them to the negative side of the coil. This grounds the ignition system and Is fixing most of the issues people are having with the digital boxes.

Posted By: hvyweight

Re: msd ignition woes - 12/17/13 06:47 AM

Quote:

Quote:

i kinda read through the replies. Did you try to remove the tach out of the senario?
i have seen tachs cause these issues.

Mike

no, haven't disconnected the tach. someone else brought this up, but this seems like a bit of a conundrum. if i don't have a tach, how do i know where it is cutting out?

it seems, so far, that the resistor plugs may have solved the breaking up issue, but i still have the rev limiter issue.

Find a timing light with rpm! Install a lower chip say 3000 rpm and bring it up to 3000 and see if the limiter cuts in.

if it works, then road test it with a higher chip.

just dont hit any big revs with no load on the motor!

good luck!

Posted By: BJS racing

Re: msd ignition woes - 12/17/13 03:29 PM

Adjust the cyl. select to 4 cyl and then back to 8 and also make sure that there is no timing being pulled out for what ever reason. To bad its not a 7al3 box. I've screwed up installing more of them than the guys a scumitt even see go through the doors. Its always the same thing too! You would think I would remember that by now.

Posted By: mickm

Re: msd ignition woes - 12/17/13 10:17 PM

Quote:

Have you tried what I suggested?

Quote:

There are many having ignition issues with the digital ignition boxes and from what I'm hearing they are caused from bad ground and the solution is pretty simple run a wire from the back of one head to the other and them to the negative side of the coil. This grounds the ignition system and Is fixing most of the issues people are having with the digital boxes.

no, i haven't. hard to keep up with all the suggestions and everything.

i'll give this a try when i get a chance.

honestly though, first step is to put my old box back in, and see how it behaves with the difference the resistor plugs are appearing to make. if it runs well, and limits where it should, i'm calling it done, and the digital is going into the trunk as a spare.

if things don't go well, i'll move on to this step.

Posted By: mickm

Re: msd ignition woes - 12/17/13 10:19 PM

Quote:

Find a timing light with rpm! Install a lower chip say 3000 rpm and bring it up to 3000 and see if the limiter cuts in.

if it works, then road test it with a higher chip.

just dont hit any big revs with no load on the motor!

good luck!

that makes sense. funny, but easier said than done. after my last attempt, the only guy i found with a timing light/tach is about 15 miles from me. but will play with this one as well if the old box doesn't do it.

Posted By: sunroofgtx

Re: msd ignition woes - 12/18/13 06:55 AM

If you like, we sell a very high quality ignition box. I'll send it and only pay us if it fixes the problem. it wires the same as the MSD, but more racer friendly setting the rev limiter and 4-6-8 dial. Call me if interested.

Posted By: GTX MATT

Re: msd ignition woes - 12/18/13 08:29 AM

Quote:

If you like, we sell a very high quality ignition box. I'll send it and only pay us if it fixes the problem. it wires the same as the MSD, but more racer friendly setting the rev limiter and 4-6-8 dial. Call me if interested.

Thats customer service

Posted By: mickm

Re: msd ignition woes - 12/23/13 05:34 AM

ok, so, on we go!

since the resistor plugs seem to have cured the breaking up issue, i decided to see if that was the issue affecting the analog box, and put it back in. i put a 6600 chip in the rev limiter, and it ran fine, all the way up to about 5400 rpm, where it rev limited.

so now i have two boxes that seem to be limiting 1000 rpm shy of where they are set, so all of a sudden the thought came to me that maybe my tach is off, (yes, i did test it before). how could both boxes be doing basically the same thing?

so i went back to the shop that has the sun timing light with the built in tach, and my tach showed 5k within a couple hundred rpm or less of what his sun tach was showing.

unfortunately, i had the analog and not the digital box in, as that would have been a great test to unplug my tach, set the rev limiter back down to something reasonable, and see where if it stopped at that point.

but i'm also done with this. i talked with rick on friday, and i'm calling him tomorrow morning and having him send a box out to me.

i'll report back when i have it installed.

Posted By: GTX MATT

Re: msd ignition woes - 12/23/13 05:53 AM

Do you have an aftermarket tach? Or the stock one with whatever set up is needed to work with MSD?

I'm not certain the Sun timing light with tach would be so accurate, is it new or old? Some "trick" timing lights don't work well with MSD type ignitions. But it could very well be reading correctly.

Hopefully you'll be set with Rick's stuff.

Posted By: mickm

Re: msd ignition woes - 12/23/13 08:16 PM

Quote:

Do you have an aftermarket tach? Or the stock one with whatever set up is needed to work with MSD?

I'm not certain the Sun timing light with tach would be so accurate, is it new or old? Some "trick" timing lights don't work well with MSD type ignitions. But it could very well be reading correctly.

Hopefully you'll be set with Rick's stuff.

tach is from charger specialties. made sure it was set up for msd, and he said it is. can only go by that.

the sun tach was from the shop where i dyno'd the engine. he has an msd box on his dyno, he knows his stuff.

so yes, on to rick's box...

Posted By: mickm

Re: msd ignition woes - 01/17/14 11:39 PM

funny, but not even sure i want to post, but here i go anyway.

i know some people have dealt with a hell of a lot more than this tracking down a problem, but i'm kind of at the end of my rope. i'm ready to throw a dual point distributor in the car and call it done.

so i got the box from rick at fire core. nice box: same footprint and wiring harness as the MSD box, just plug it in.

which i did. set the rev limiter at 6300, and the engine stopped at about 5600. was so despondent i just took the car home and put it in the garage, didn't even bother to mess with anything else.

recent updates were: resistor plugs have stopped the missing and breaking up, but it rev limits well below what is set on the box, with the MSD digital, the MSD analog, and now the FireCore box. MSD box is set at 7100 and it limits at 6100.

i did put an external tach on the car, and with no load was only 1-200 rpm different at 5000 rpm. maybe i should have gone to 6000, and maybe i need a different tach hooked up in the car.

as i said, i'm at wits end, and don't know where else to go. rick has offered to send me a distributor, so i may as well try that.

any thoughts are appreciated, but please look back through the thread, especially the first post. i've done SO MUCH with this so far, hard to imagine what it could be that is causing this issue.

Posted By: GTX MATT

Re: msd ignition woes - 01/17/14 11:50 PM

I would put a reliable tach in the car to watch. The only other issue I could think of might be a rotor phasing issue or an issue with the pickup in the distributor.

You don't have solid core plug wires too, do you?

Posted By: mickm

Re: msd ignition woes - 01/17/14 11:56 PM

Quote:

I would put a reliable tach in the car to watch. The only other issue I could think of might be a rotor phasing issue or an issue with the pickup in the distributor.

You don't have solid core plug wires too, do you?

i have tried two different distributors, same issue. doesn't mean both of them aren't whacked, you never know.

firecore wires, not solid core.

and yes, i'll search for a good tach to put in the car for testing...

Posted By: dakotawilly

Re: msd ignition woes - 01/18/14 12:06 AM

doesn't msd have a travelling circus attending the bigger shows or races?you may want to look into that and let your brain rest before theres dynamite involved....

Posted By: mickm

Re: msd ignition woes - 01/18/14 01:46 AM

Quote:

doesn't msd have a travelling circus attending the bigger shows or races?you may want to look into that and let your brain rest before theres dynamite involved....

1st point is interesting, second is probably the soundest advice i've had on this in a while!

Posted By: SCATPK

Re: msd ignition woes - 01/18/14 02:49 AM

Completely disconnect the in-dash tach you have and give it another try.

Posted By: BobR

Re: msd ignition woes - 01/18/14 03:23 AM

Quote:

Quote:

I would put a reliable tach in the car to watch. The only other issue I could think of might be a rotor phasing issue or an issue with the pickup in the distributor.

You don't have solid core plug wires too, do you?

i have tried two different distributors, same issue. doesn't mean both of them aren't whacked, you never know.

firecore wires, not solid core.

and yes, i'll search for a good tach to put in the car for testing...

Not a big fan of Firecores. Have you tried another set? I use MSD wires for everything I own. The rotor may be out of phase. You have to check this and don't assume just because you have had two distributors that it can't be that. Drill a hole at number one and scribe a line that bisects the rotor then aim the timing light into the hole and rev it to 6000 RPM or whatever the highest rpm it will go up to 6000. Where is the line? It should be aimed at number one. What is your total timing set at? Do you have a degree'd damper so you can check this?

Posted By: mickm

Re: msd ignition woes - 03/17/14 09:18 PM

so, the latest. i have been doing many other things, (like life�), as well as on the car, but here is the latest.

i disconnected the tach not far from the MSD box, so the wire was still connected at the tach in the dash, and running from there all the way through the engine compartment to where it was disconnected not far from the box.

there was no change in the behavior of the engine, but i noticed that the tach was jumping up to around 1000 rpm as i was driving! i then tried to reach under the dash and disconnect the wire at the tach, and with my fingers inadvertently made a connection between the power to the tach and the input from the MSD box. the tach immediately jumped to 3000 rpm, and from there followed the rpm of the engine, i.e. as i revved the engine, the tach responded to it!

so i'm assuming from this that there is so much RF bouncing around inside that engine compartment that the input wire to the tach is acting like an antenna, picking up the signal and sending it to the tach.

local theories are that the very, very low resistance of the fire core wires are the culprit. i finally have another set of wires, (actually labeled suppression on the wires) that i am going to try. will give an update once that happens.

once i have tried the wires, i only have one other (somewhat involved) option, and that is to relocate the box to the passenger compartment. but if it really is RF, that is the issue, then the wires should show that.

i'm still not very far from just chucking the whole thing and going to a dual point, but i'll see what the new wires do.

stay tuned...

Posted By: Thumperdart

Re: msd ignition woes - 03/18/14 02:25 AM

Don`t see the Firecore`s "high resistance" as an issue but whatever and all my ign. stuff is in the car mounted on the firewall on the pass. side and my MSD 6200 box is older than I can remember. You`ll find it but points aren`t a solution other than weeding out your dist.............

Posted By: Joshs68

Re: msd ignition woes - 03/18/14 03:12 AM

If it was fine on the dyno with an FBO mopar type box why not put one back on it in place of the MSD? I have a chrome box someplace I'll let you try out if you want to. At least to see what happens.

Doesn't help with a the rev limiter, but MSD makes a small stand alone piece for that purpose.

My 470 pulls hard through 6200 plus with a chrome box, FBO setup mopar distributor and fire core wires.

Posted By: Jared_Jordan

Re: msd ignition woes - 03/18/14 04:31 AM

I've missed a lot of this post, but on my Stocker, everytime we've had the engine on the dyno with a digital MSD or had a digital MSD in the car, it won't run right. Had a Mopar Mechanical Tach Drive distributor in it and thus couldn't use MSD's trigger wire.

When we put the engine on the dyno, we'd have to take a 7AL-2 and wire it up before the engine would take any kind of load.

Posted By: Chris'sBarracuda

Re: msd ignition woes - 03/18/14 04:51 AM

MSD Digital6..

Check the Moparts google search.. Lots of stuff there..

Here's one..

https://board.moparts.org/ubbthreads/showflat.php?Number=1827249

Chris..

Posted By: mickm

Re: msd ignition woes - 03/18/14 05:20 PM

Quote:

MSD Digital6..

Check the Moparts google search.. Lots of stuff there..

Here's one..

https://board.moparts.org/ubbthreads/showflat.php?Number=1827249

Chris..

checked that out, and it is saying the same thing i'm suspecting. so now to just check it out and see if i can shield the box from the RF. i don't know about the plug wires, but it is the only thing i haven't changed at this point. i may move the box into the engine compartment, but only if i have a hint that will work.

Posted By: mickm

Re: msd ignition woes - 03/18/14 05:24 PM

Quote:

Don`t see the Firecore`s "high resistance" as an issue but whatever and all my ign. stuff is in the car mounted on the firewall on the pass. side and my MSD 6200 box is older than I can remember. You`ll find it but points aren`t a solution other than weeding out your dist.............

not high resistance, low resistance, thereby throwing lots of RF around.

and while i agree that going to a points distributor isn't exactly a "solution", at this point the main thing on my mind is how well it ran with a points distributor in there, and how much time and effort i've gone through to deal with this issue, and am still nowhere. of course, i could be one step away from solving it, and not know it yet, but then i won't know until i get there!

Posted By: Thumperdart

Re: msd ignition woes - 03/18/14 06:38 PM

Quote:

Quote:

Don`t see the Firecore`s "high resistance" as an issue but whatever and all my ign. stuff is in the car mounted on the firewall on the pass. side and my MSD 6200 box is older than I can remember. You`ll find it but points aren`t a solution other than weeding out your dist.............

not high resistance, low resistance, thereby throwing lots of RF around.

and while i agree that going to a points distributor isn't exactly a "solution", at this point the main thing on my mind is how well it ran with a points distributor in there, and how much time and effort i've gone through to deal with this issue, and am still nowhere. of course, i could be one step away from solving it, and not know it yet, but then i won't know until i get there!

My bad, still don`t see that as a problem but I`m all ears and waiting to see your findings.

Posted By: mickm

Re: msd ignition woes - 03/26/14 07:01 PM

ok, again the latest.

swapped the fire core wires out to some stock type wires, (had the label "suppression"), on them.

if you remember, in order to have the engine rev limit at 6100, i have to set the limiter to 7100. so i set it back down to 6100 in case this made a significant difference.

took the car out and it got up to about 5700 or so, but was missing so badly it couldn't continue beyond that.

put the fire core wires back in, and it hard limited at about 5000. huge difference in behavior.

so i think it is pretty conclusive. only 2 things have made a difference since i started this, (3 if you count eliminating the MSD box entirely and putting in a dual point): resistor plugs and stock type wires.

it seems pretty obvious to me now that the issue involves the amount of RF under the hood, and the box is extremely sensitive to it. (yes, i know, many people have pointed that out, but i had to get there step by step). i don't know why my situation is so different than so many others, but for some as yet unknown reason, it is. everything is basically stock under the hood aside from the ignition system.

next step; rig a harness so i can temporarily relocate the box to the passenger compartment, and see what that does. if for some reason that doesn't take care of it, then i'm going to start looking at getting a dual point distributor in there.

Posted By: an8sec70cuda

Re: msd ignition woes - 03/26/14 07:10 PM

Have you tried the old analog style MSD 6AL on it?

I had all kinds of misfiring issues w/ the MSD Digital 6...not the newer digital 6AL like you have. Sent it back, got a new one, same thing. Had it mounted under the dash where my old style 6AL had been. Ended up getting my money back and have been running the old school 6AL ever since w/o any problems.
Those digital boxes are extremely sensitive.

Posted By: Thumperdart

Re: msd ignition woes - 03/26/14 07:14 PM

Hearing about lots of issues w/those boxes myself and am still runnin my old reliable 6-a box inside the car.........

Posted By: GTX MATT

Re: msd ignition woes - 03/26/14 07:15 PM

Where is your box mounted? Is it near the alternator or anything like that?

You've been a patient guy with this, I would have smashed it with a sledge hammer by now.

Posted By: mickm

Re: msd ignition woes - 03/26/14 08:16 PM

the box is mounted below the battery tray.

my old analog box does roughly the same thing, although i did not try it with the new wires.

it's not so much that i've been patient, just that i've been able to walk away from it for periods of time.

at this point i'm convinced that it isn't so much with the box, (although the latest tests show that it is probably RF, and these boxes should be less sensitive to that), as something with the car, but i can't figure out what.

a new realization came to light, but talking it over with a friend who specializes in wiring and these cars, we have somewhat ruled it out.

there are times when the starter does not engage when turning on the key. i've narrowed it down to the connection at the bulkhead. so if no response when turning the ignition key, i can just reach under the dash and wiggle the connection around a bit, and it fires. sometimes it doesn't pop up for months, a year or more, and sometimes it pops up more often, but is always solved that way.

but that is the connection going to the starter relay, not the connection to the ballast resistor.

i have checked the connections at the bulk head on the engine compartment side, but haven't yet from under the dash. things look good on this side.

so it is possible that there is a bad connection for the wire that runs to the ballast resistor as well, but there has never been any evidence of that. add to that that with the points distributor in place, where (if i understand correctly), the current to the coil actually flows through this connection, it ran great, that would lean towards a good connection. with the MSD box, it supplies voltage to the coil through it's own wires, and so this connection isn't even used.

so i'm still looking into that.

Posted By: MR_P_BODY

Re: msd ignition woes - 03/26/14 09:44 PM

A bad connector at the bulkhead could create your
problems.. a higher draw would react to it more than
a lesser draw... I would correct that before moving
on

Posted By: sshemi

Re: msd ignition woes - 03/26/14 11:20 PM

This wont help at all but just want to say that my digital 6 have gone south during the winter. Was going to take the car out of winter storage and it dont start.
So started some trouble shooting and come up to that the box only gives one spark per dist rev when turned slowly, like during starting.
If i turn the dist faster (by hand) it functions properly.
But this box have given me too many head aces so it goes in the trash.
So it broke without even touching/using it.

Posted By: sshemi

Re: msd ignition woes - 03/26/14 11:47 PM

Hey im the 100th poster of this topic!
Do i win another digital 6 that doesnt work?

Posted By: cudatom

Re: msd ignition woes - 03/27/14 04:19 AM

Quote:

oh, and the guy from MSD just told me that i CANNOT run the blaster coil horizontally. it must be run vertically, or there isn't enough oil to cover the windings, and it will heat up and break down.

from the coil instructions from MSD:

It is recommended to mount the PN 8202 and 8223 coils in an upright position. The High Vibration Coil, PN 8222, can be mounted in any position due to its epoxy potting compound.

Been running the same Blaster coil for 20 yrs and has always been horizontal, never had an issue.

Posted By: racerhog

Re: msd ignition woes - 03/27/14 07:47 PM

Recurve a known good dist.... Get a good MSD Box..

Posted By: camastomcat

Re: msd ignition woes - 03/27/14 08:27 PM

Here's a stupid question, and perhaps it's already been answered.....do you have the MSD tester?

Posted By: B3422W5

Re: msd ignition woes - 03/27/14 08:59 PM

Been reading this post with interest...from my days as a field engineer for a computer maker it perked my interest.

Low resistance of the plug wires shouldn't be a factor, good or bad, assuming the wires are shielded, which most any wires on the market are.

Resistance is defined as r = E over I...e voltage, I is current. You( in a perfect world) want as little drop in voltage and current to where they are used, as possible. The more resistance a given foot of wire has, the more voltage and current it takes to overcome it, thus reducing effectiveness. Look at a plug wire as a drain in a sink. If the drain is perfectly clear, it will dispose of the most water. If it gets clogged up with hair, etc less water will pass through the drain.
Plug wire is the same way, less resistance, more voltage and current get through, more resistance less voltage and current.
That all said, a few ohms difference( the reading of resistance) in a given foot of plug wire isn't going to make a hill of beans difference in performance Its just a sales tool to sell wire..10 ohms or 100 ohms per foot, both are still way overkill. Msd stuff puts out a TON of juice
My guess is the digital box you are using is picking up some kind of unshielded interference.
My first thought would be to put the digital 6 on the fenderwell away from everything and try it. I had a digital 6 in my Duster that replaced a bad 6al box, never a peep out of it..was installed circa 2005-2006, and is still in the car today( I no longer own it)
In short, move the box away from possible interference and try it, I suspect the issue will go away. just my thought..

Posted By: mickm

Re: msd ignition woes - 03/27/14 09:47 PM

Quote:

Here's a stupid question, and perhaps it's already been answered.....do you have the MSD tester?

didn't know there was a tester? where do i find one?

Posted By: Paul_Fancsali

Re: msd ignition woes - 03/27/14 09:50 PM

Said this before Take the MSD and walk over to the trash can and dispose. Now get your point dist go buy a pertronix and install and I'll bet problem solved No you won't have a rev limiter but how often do you race the car? I know there are a lot of guy's getting rich because everyone has to have what some one else has in their car and they will go faster WRONG. I stick to pertronix or good old Kettering Points

Posted By: mickm

Re: msd ignition woes - 03/27/14 09:51 PM

Quote:

Been reading this post with interest...from my days as a field engineer for a computer maker it perked my interest.

Low resistance of the plug wires shouldn't be a factor, good or bad, assuming the wires are shielded, which most any wires on the market are.

Resistance is defined as r = E over I...e voltage, I is current. You( in a perfect world) want as little drop in voltage and current to where they are used, as possible. The more resistance a given foot of wire has, the more voltage and current it takes to overcome it, thus reducing effectiveness. Look at a plug wire as a drain in a sink. If the drain is perfectly clear, it will dispose of the most water. If it gets clogged up with hair, etc less water will pass through the drain.
Plug wire is the same way, less resistance, more voltage and current get through, more resistance less voltage and current.
That all said, a few ohms difference( the reading of resistance) in a given foot of plug wire isn't going to make a hill of beans difference in performance Its just a sales tool to sell wire..10 ohms or 100 ohms per foot, both are still way overkill. Msd stuff puts out a TON of juice
My guess is the digital box you are using is picking up some kind of unshielded interference.
My first thought would be to put the digital 6 on the fenderwell away from everything and try it. I had a digital 6 in my Duster that replaced a bad 6al box, never a peep out of it..was installed circa 2005-2006, and is still in the car today( I no longer own it)
In short, move the box away from possible interference and try it, I suspect the issue will go away. just my thought..

well, our theory is that those low resistance wires are putting out enough RF to disturb the box.

i agree that it is not specifically the box, but something on my car, as i had the same behavior with FireCore's ignition box. but what it is has eluded me so far.

i am going to go through and check the connections at the firewall, will take care of that first. possible that a spotty connection isn't putting out a full signal, confusing things.

but it is very, very interesting to note that the only two things that have made a difference have both been related to resistance in the system: resistor plugs and a higher resistance spark plug wire.

next step is to rig a quick harness and put the box well inside the passenger compartment. as i said, if that doesn't take care of it, i give up, and am going to points.

Posted By: 70sixpkrt

Re: msd ignition woes - 03/27/14 11:11 PM

Quote:

didn't know there was a tester? where do i find one?

I had a problem with my MSD 2 years ago and brought mine to Gotelli Speed Shop. They had a tester there. Found out my MSD was good. Different problem than yours. I think any speed shop would have a tester.

Posted By: Chris'sBarracuda

Re: msd ignition woes - 03/28/14 12:55 AM

Quote:

Said this before Take the MSD and walk over to the trash can and dispose.

This..^^^^^^^^^

Chris..

Posted By: dvw

Re: msd ignition woes - 03/28/14 03:56 AM

I use shielded wire for both my pick-up and coil harness. It has braid around the two wires (which are also twisted) that can be grounded to the box. PM me what lengths you need and I'll send you some.
Doug

Posted By: mickm

Re: msd ignition woes - 03/28/14 06:39 PM

Quote:

Quote:

Said this before Take the MSD and walk over to the trash can and dispose.

This..^^^^^^^^^

Chris..

chris, not far from that, and probably would have done it a while ago except for the fact that the firecore box did the same thing. so it's more something specific to the car than the box.

but if relocating the box to the passenger compartment doesn't work, then that is probably what will happen!

Posted By: mickm

Re: msd ignition woes - 05/13/14 08:32 PM

well, just to keep this thread alive. one more test to go. i just made a 10 ft wire harness extension so i can put the MSD box in the passenger compartment as a test. hopefully i'll get to that soon, (most of the time i'd rather drive the car than work on things that don't affect driving it�).

this is it. if this doesn't solve the problem, i'm chucking the entire system and going with something new. haven't figured out what that is yet, but the best that car has ever run was with a 40 year old dual point distributor and an $18 napa coil, so that just may be it.

will post as soon as i have something...

Posted By: 70sixpkrt

Re: msd ignition woes - 05/13/14 08:41 PM

Mick I have mine bolted on the side of the radiator support for the last 10 yrs with no problems. My other buddy has it in the same spot with no problems.

Attached picture 8143442-MSD6AL.jpg

Posted By: mickm

Re: msd ignition woes - 05/13/14 09:44 PM

Quote:

Mick I have mine bolted on the side of the radiator support for the last 10 yrs with no problems. My other buddy has it in the same spot with no problems.

it's one of those bizarre things. the only thing i can say so far is that the box is affected by the RF running around under my hood. i have the box mounted under the battery at the moment. i'm thinking that with my situation, that will still be too close to all of it, but who knows?

i'm going to try the passenger compartment, and if that does it, done. that's where it will go. if not, another type of system is in order.

Posted By: an8sec70cuda

Re: msd ignition woes - 05/13/14 09:46 PM

mickm...yours is digital, his is not. The digital boxes are very sensitive to RF interference.

Posted By: mickm

Re: msd ignition woes - 05/13/14 09:55 PM

Quote:

mickm...yours is digital, his is not. The digital boxes are very sensitive to RF interference.

yeah, just saw that. good catch.

well, on with the plan! in the passenger compartment it goes!

Posted By: mickm

Re: msd ignition woes - 06/19/14 08:48 PM

so about to put an end to all this nonsense.

with the box in the engine compartment and the rev limiter set to 6100, the engine started to miss above 4k and was a mess by 5500 or so. usual, nothing new here.

made an extension and moved the box to the passenger compartment, and no miss at all, but did rev limit at around 5500.

now although i did a simple check on the tach earlier, i don't know that the tach is truly accurate.

so, this weekend i'm moving the box to the engine compartment, and once that is done i'll have a known good auto meter tach temporarily installed to see how accurate my tach is. once i know that, i'll go from there.

damn this has been a long, ugly one� the bad part about it is that through all this i didn't really learn anything in particular, just a long, frustrating haul...

Posted By: sunroofgtx

Re: msd ignition woes - 06/19/14 11:09 PM

Hopefully that will be it. You need closure..:)

Posted By: Thumperdart

Re: msd ignition woes - 06/19/14 11:24 PM

Quote:

so about to put an end to all this nonsense.

with the box in the engine compartment and the rev limiter set to 6100, the engine started to miss above 4k and was a mess by 5500 or so. usual, nothing new here.

made an extension and moved the box to the passenger compartment, and no miss at all, but did rev limit at around 5500.

now although i did a simple check on the tach earlier, i don't know that the tach is truly accurate.

so, this weekend i'm moving the box to the engine compartment, and once that is done i'll have a known good auto meter tach temporarily installed to see how accurate my tach is. once i know that, i'll go from there.

damn this has been a long, ugly one� the bad part about it is that through all this i didn't really learn anything in particular, just a long, frustrating haul...

Electrical can be a brain exerciser for sure but you`re gettin stuff done and hopefully you`ll figure it out. I still have the same MSD-6 box and coil from many years ago and always mounted in the car and zero issues.............good luck.

Posted By: SNK-EYZ

Re: msd ignition woes - 06/20/14 08:46 AM

Mick,
Have you run it on a dyno?

I just saw this thread and was wondering if I'm having the same issues.

I've got a 6AL2 digital on my car and it's definitely having issues.

Rev limiter set at 6500 and it wacks out about 5400.

The power curve drops off but it "tries" to recover.

I'll have to set the rev limiter higher and see how it does.

Posted By: an8sec70cuda

Re: msd ignition woes - 06/20/14 02:01 PM

Have you tried disconnecting your tach? I have seen a tach cause all sorts of problems w/ misfiring even though it seemed to be working ok.

Posted By: jbc426

Re: msd ignition woes - 06/20/14 05:13 PM

Mick, You have the most amazing series of mysterious problems. I thought I was the only one who goes through this BS.

Best of luck. That car is awesome!

Posted By: MR_P_BODY

Re: msd ignition woes - 06/20/14 05:46 PM

Quote:

Have you tried disconnecting your tach? I have seen a tach cause all sorts of problems w/ misfiring even though it seemed to be working ok.

I seen that problem on my brothers chevy... when I
finally took off the tack lead it straightened right out

Posted By: mickm

Re: msd ignition woes - 06/20/14 08:24 PM

Quote:

Have you tried disconnecting your tach? I have seen a tach cause all sorts of problems w/ misfiring even though it seemed to be working ok.

yes, have tried this. didn't make any difference. even put a disconnect down near the box so that the wire if disconnected at the tach, (even though it wasn't conducting), still wasn't acting as some sort of antenna.

Posted By: mickm

Re: msd ignition woes - 06/20/14 08:29 PM

Quote:

Mick,
Have you run it on a dyno?

I just saw this thread and was wondering if I'm having the same issues.

I've got a 6AL2 digital on my car and it's definitely having issues.

Rev limiter set at 6500 and it wacks out about 5400.

The power curve drops off but it "tries" to recover.

I'll have to set the rev limiter higher and see how it does.

the engine was broken in on a dyno, and ran great.

for everything i have tried, (and if you look at the beginning post you will see the list), only 3 things have made a difference:

- resistor plugs
- resistance plug wires
- moving the box out of the engine compartment.

in the end i know it is still something funky with my setup. yes, the digital boxes have problems, but many, many people run them in or around the engine compartment without problems� or at least problems that they notice.

but i'm done messing with it. i am going to try one more thing though. i want to put the dual point distributor back in and eliminate the box altogether once more and compare how it feels. the time i did that i only took it for a few short runs and it felt fantastic. but now i want to check it again, as with the box in the passenger compartment i want to compare the two.

Posted By: mickm

Re: msd ignition woes - 06/20/14 08:32 PM

Quote:

Mick, You have the most amazing series of mysterious problems. I thought I was the only one who goes through this BS.

Best of luck. That car is awesome!

john, don't i know it! to be honest, i'm starting to lose interest. seems like the time i spend trying to diagnose and fix problems is starting to tip the fun scale in the other direction.

Posted By: SNK-EYZ

Re: msd ignition woes - 06/20/14 08:38 PM

Quote:

to be honest, i'm starting to lose interest. seems like the time i spend trying to diagnose and fix problems is starting to tip the fun scale in the other direction.

I can relate to that feeling completely.

There are days that I'm tired of messing with it and think that a new Challenger would be less hassle and more fun to cruise in.

Posted By: Challenger 1

Re: msd ignition woes - 06/20/14 08:39 PM

Quote:

Quote:

Mick, You have the most amazing series of mysterious problems. I thought I was the only one who goes through this BS.

Best of luck. That car is awesome!

john, don't i know it! to be honest, i'm starting to lose interest. seems like the time i spend trying to diagnose and fix problems is starting to tip the fun scale in the other direction.

Been where you are now.

Unless it's a race car, I have found much more fun with my cars using stock parts. I have already gone really fast in my diggers, so for me it's now all about reliability with my muscle cars. Some stock parts perform just fine on the streets and don't keep your car from performing great, like fuel pumps and ignition.

Posted By: mickm

Re: msd ignition woes - 06/20/14 11:14 PM

Quote:

Been where you are now.

Unless it's a race car, I have found much more fun with my cars using stock parts. I have already gone really fast in my diggers, so for me it's now all about reliability with my muscle cars. Some stock parts perform just fine on the streets and don't keep your car from performing great, like fuel pumps and ignition.

not having had the experience of really racing, the fun comes from having a car that is fast that can be used on the track as well as the street. nice situation to be able to get the go-fast out of your system on the track to that extent.

i'm starting to move more to your point of view, i must admit...