I am correct in check dwell with the meter with engine running, I put the + lead on the + side of coil and - lead on a engine ground to get correct reading?

or is it both side of coil?

with cap off and points snug and using a small flat blade in the points base notch moving it to open the gap or close gap as needed to get the dwell reading as it is cranked over.

if this is correct, then I have found the cheap points do not have a long enough slot to get 30* dwell and I only get 25* dwell.

maybe a NOS set of mopar points is what I need to get it set.

TIA

+lead(usually red) goes on - side of coil and - lead(black) goes to good ground.

Mike, I've had dwell meters with three leads, and others with two. I suspect the reason is a tachometer function as well as dwell readings. It's been a while so had to think on this one.

As has been said already, a two wire setup hooks as described. My 3 wire caught both sides of the coil plus a ground.

I have to admit I've never tried adjusting dwell by just cranking the engine over. On rare occasions I've slightly elongated the adjustment slot with a rat tail file to obtain more travel. In any case I've always made the readings with the engine running. I'd be interested in other opinions on this.

I have always set the final number with the engine running to allow for any variation due to worn bushings etc. If something is really worn it obviously needs rebuilding.

And to the OP, you are aware that closing the gap increases the dwell right ??? Also make sure your meter is on the appropriate scale IE: 4, 6, 0r 8 cyl.

I like 27-28° of dwell and use a performance coil. As was said - you can file the hole larger if you need more. You also want to make sure you're using the truangular shaped screwdriver point to adjust them and not just prying on the upright part of the set of points.

Red lead goes to negative side of coil and black to ground.

the red lead needs to go to the side of the coil that the points wire connects to which is neg.the bigger the gap the smaller the dwell reading. If the dwell changes when eng.rpm is increased the dist.has worn bushings.Dwell is the amount of time the points are closed vs the amount of time there open.the more dwell the longer the coil has to charge up giving a hotter spark that's why the came out with duel point dist.it gives a longer dwell time.

ok. thanks. that is just the info I needed. been running pertronix points conversion so long I forgets how to troubleshoot points.

red test lead to - side of coil

black test lead to good ground

no, I did not know closing the gap increases dwell. seems I went the wrong way and it got better.

could be why I am at 25* with a wide gap?

I set points with a feeler gauge at .016 and ran it. now checking with a meter I am a little fused as in why I open the gap wide and it seemed to get better throttle response.

I will retest and see what I got now I am less fused.

As said: red to coil neg primary. gap/dwell/point life are inversely proportional. You can set the gap pretty much anywhere you want it (.017 is a good ballpark) just keeping in mind that longer dwell time/smaller gap give more power and shorter point life over time (good for high perf) as you'd be changing em out sooner as needed. For max power set the gap at .005 & if it will start then that will give you the most (as said) coil saturation time for the most power and the shortest point life over time cuz with the points touching/current flowing there is more time for them to burn (over time/wont happen overnight) & if it wont start at .005 go up in .003" deg increments till it will start. For Grandmas' DD you'd want the largest gap for the least dwell time (I'd start at .017 & maybe go up to .020"}. Perf point sets are as you know higher quality & likely have more spring tension for bounce resistance at higher RPM's

how do you adjust the points gap for dwell with the cap on and engine running?

I thought you do it with cap off, engine cranking, meter readings while cranking/adjusting points gap with screwdriver tip.

I had some GM junk that had a window in the cap to adjust points with a flex driver while running and watching the meter readings.

On a non window distributor, it is trial and error to get the dwell right. IE: cap on, measure the dwell, Cap off, adjust.
Repeat.

keep in mind small adjustments make a substantial difference, and that tightening the adjustment screw can change the adjustment. Have FUN!!!

If I remember correctly most points were set at .018 gap by the tune up guides.

I set points with a feeler gauge at .016 and ran it. now checking with a meter I am a little fused as in why I open the gap wide and it seemed to get better throttle response.

I will retest and see what I got now I am less fused.

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When you open the point gap you are advancing the timing unless you reset the timing after opening the point gap. But when you open the gap the points open sooner and it fires the coil sooner which advances the timing and gave you better throttle response. General rule of thumb was point gap about 16 to 18 and dwell about 27 to 30 for single points. Get it in them setting and it will be fine. Course dual points will have more dwell as thats the reason for dual points for more coil saturation time and stronger spark. Ron

Anyone old enough to remember using a match book cover to set the gap.
Showing my age.

not a problem because we always had matches to go with the "luckys" or "camels" rolled up in our t shirt sleeves. when they came out with those new fangled "throw away" bic lighters, we found out those didn't fit right for setting the points, so we just quit smoking and went to electronic ignition....

did it last week myself.

that was when a set of NOS Accell super stock points with a 32oz spring went out.

they went in and adjusted them with a feeler gauge. ran them 18 months trouble free.

upgraded to FC-RTR dist/coil. a few issues x2 that are now resolved and ready to try again. = coil relocation/rewire.

so I pulled the point dist after 18 months trouble free, put it back in a month later and ran it a couple months.

then one day I am rolling hard and it stops running, no start = no fire = the pad/tip on points burnt right off the arm.

installed cheap points and been doing a little skipping popping but other wise ran good once under way. just could not jump on it hard. ez pz and it did fine.

so now with a new meter (which is something I never had to use) I am playing with it. got it running way better now. so will be looking into some good NOS mopar/Accell points for it.

I have a FBO mech advance limiter in there with initial at 18* and mech at 14* for a total of 32*

I found the whiplash cam seems to like 32* better than 38* with it set 18*/18*

I will pick up a new set of points and retune.

I want to dial in the points dist before swapping back to the FC system. that way I am ready if it fails.

the metal contact tip not the fiber piece that rides on the shaft cam lobe correct? that is pretty rare, I'd suspect an oil film on the point contact faces or a very high draw coil or a cheap set of point or maybe it it is a good set then one that came thru with bad metallurgy (Murphys law) plus alot of dwell gives more burn time but rarely burns off the tip!. You are lightly lubing the cam lobes for the fiber piece?

If you should happen to leave the key on for a good while with the engine not running it could burn up the points.

no I don't leave the key on with points.

the metal tip welded to the arm that the contact pad is secured too. almost 2 yrs service with no adjustments on that set.

cant get any better than that. they were a nice NOS Accell 32oz set.

I am a little more fresh with it and not so much fused on the basics.

I really should get a pertronix points conversion and be done with it.

not sure about the ignitor III set up though.. it looks like it does the most for the $

OH! any reason I cant remove the cap and check dwell reading and adjust as it is cranked over??

that's just the way I have always seen/done/told how to do it. well other than the GM window cap.

should be the same reading correct?

if I understand correctly the ignitor III adjust dwell and coil saturation time as needed.

is that all hype or does it really do that much?

(1) now that you mention it I heard of doing that back decades ago so if it worked then it would work now. (2) I have the ignitor III for the stock car but ain't got around to it yet (I have a point dist/new bushings/reamer) so no feedback here (& I have the matching coil for it) EDIT on my bench there's alot of play between the two plates & I'm gonna call em & see if that is OK or if I should return it