Late model small dia. hei dist.

[ezstriper]

Has anybody tried to run a late model small dia HEI dist from GM ? the 87 and newer that was used in computer controled cars/trucks. I don't which one had it but there is one(or all) with the advance curve built into the module and works without any computer control. the early hei work great but won't clear a tunnel ram, just thinking Rob...

[Foggerjet]

Those Gen II Hei's use an EST module, a little flat thingy that usually mounts on the firewall of the O.E. vehicle. This works in conjuction with the ECM, Coolant temp, Knock sensors and MAP or MAF to control timing. There is no mechanical advance, the EST and ECM control the amount of advance or knock retard. Even if you get spark, the timing will be locked, which may be what you want.Those Distributors also have a 4 wire plug that controls injector pulse on TBI and TPI stuff. It may be easier to just get an aftermarket dist. You know it will work without any drama.
just .02
fog

[ezstriper]

Thats not true on all of these units, as I have 2 on a pair of 454 crusader marine engines using stock apearing gm small hei dist. they run nothing but the dist. no external parts or sensors, the timing curve is in the module in the dist. to set the timing you unplug a 2 wire connector, reverse it reconnect set base timing, reverse connector and you are good to go, real simple set-up, I have been told before that there is in fact the timing curve in the module and the ecm just allows it to work, and also been told that you should only replace modules with gm one as there are differnt applications and the aftermarket one are usaully one size fits none. I am going to try get the wiring dia. for the crusader engines and try to find out what module they use, I tuned the boat up last year, used std accell cap, rotor, for 87 and later vehicles, and i thought i saw a gm # on the module, but not sure, if this works out could be a much cheaper and more reliable setup than some(MSD) setups, just was seeing if anybody tried such a thing, thanks Rob...

[Jetmugg]

I had the small cap HEI on the 454 in my Gullwing. You are correct, there is a default curve built into the dist. which works fine for a jetboat application. There is a "dummy" 2-wire harness that you have to use to set the initial timing. I ended up just using my light to set the "all in" timing at about 3000 rpm, and just let the initial timing fall wherever it did. These dist's. work great, and they will clear a tunnel ram, which a regular HEI will not.
SteveM.

[ezstriper]

Thanks, I thought it might just be the ticket as these H/P new dist. are pretty cheap and work well, I've used the large dia one in the past, how did you wire yours up, thanks Rob...