HEI acting like a rev limiter w/ video

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dart_68

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I've got a problem that I think is originating in the ignition system. When I stab the pedal there is a split second bog then revs fine to 5000 when I pull my foot off. But when I rev the engine up slowly it will go a little past 2000 then drop to back to 2000 and sit there sounding like a rev limiter and the tach needle quivering even though I am still moving on the pedal. After a couple of seconds it will begin to rev up again. I've disconnected the tach to see if that was the problem but it was the same.

The ignition system is a standard type Mopar distributor with an HEI 7 (8?) pin module and coil. Ballast resistor has been bypassed. Engine is a 1990 360LA. Internally stock but has a performer manifold and 4bbl Holley and headers.

I'll post the video as soon as I figure out why I can't get it off of my phone...

Let me know what other info you need. Thanks!
 
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First, put a timing lit on there, and look for the dropped sparks and watch the advance, to see what it's doing.If the advance is steady and around 20 degrees or more, and the strobing is normal, then
second;
it could be a fuel problem. 2000rpm is still on the transfers but about to transition to the mains. If you have a metering rod carb, then I'd provide some enrichment first and see what happens.
If a Holley, first I's stick a 10.5PV in there and second I'd go up one primary jet size, and again see what happens.
If you think it's going lean, the easy test is to wad up a shoprag and start covering the primaries with it, while it's in stutter-mode. If it smooths out and starts acting normal; badaboom.
 
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I did one of the one wire E-bay distributors and just used a stock type coil it did not like it acted kind of simular to what you described. put the proper E-core type coil on and it woke it right up.
 
I've got a problem that I think is originating in the ignition system. When I stab the pedal there is a split second bog then revs fine to 5000 when I pull my foot off. But when I rev the engine up slowly it will go a little past 2000 then drop to back to 2000 and sit there sounding like a rev limiter and the tach needle quivering even though I am still moving on the pedal. After a couple of seconds it will begin to rev up again. I've disconnected the tach to see if that was the problem but it was the same.

The ignition system is a standard type Mopar distributor with an HEI 7 (8?) pin module and coil. Ballast resistor has been bypassed. Engine is a 1990 360LA. Internally stock but has a performer manifold and 4bbl Holley and headers.

I'll post the video as soon as I figure out why I can't get it off of my phone...

Let me know what other info you need. Thanks!

It happens so you could be right.
I had an HEI module on my car once that went out completely at full throttle and came back on when I let off.
It scared the guy I was passing so bad he almost went right off the road.
Sounded like a high powered rifle shot.
Checking into it later I found out the module wouldn't rev over about 4k, but I keep a spare module in the trunk and it's been fine since.
 
Here's the video of the tach showing what it's doing, both when I press on the pedal somewhat slowly and also when I stab the pedal. You can see the "rev limiter" type action when I rev slowly at about 2000 rpm.
 
That's weird. I've had a tach that had a rev limiter built into it do the very same thing.

Said tach met hammer. Fixed that issue.

I'm stumped.

Sure is weird though. You have something to tell your family about tomorrow though.
 
Here's the video of the tach showing what it's doing, both when I press on the pedal somewhat slowly and also when I stab the pedal. You can see the "rev limiter" type action when I rev slowly at about 2000 rpm.


I really think that is the module.
 
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