ECM /Distributor Upgrade

[edovigi]

Looking for advise to upgrade/replace the ECM(part # 16005520) and Distributor on a 1979 231 v6 turbo Buick engine that is in a 1981 Buick regal sports coupe.
The engine runs but the ECM does seem to be retarding the timing under load . Originally I had no spark at the distributor I replaced the ECM with a spare I had and it fired right up but didn't run as smooth as before ,When I removed the cap the counter weight nylon pins bushings and the springs where worn and the magnet that is at the base of the distributor at the secondary coil was in pieces. I repaired the distributor weights and magnet issue but it back fires or detonates at about 2000 rpm. If i run a standard distributor it runs strong no hesitation or sputtering .I don't want to run it this way i am afraid it will eventually damage the engine. Any advise is greatly appreciated.

 

[BEATAV8]

The “before black” guy is Rich G.
He’s the fella to talk to. His 82 GN uses a carburetor on E85 and an HEI with an MSD box to control timing and pull back as it goes into boost. The MSD box has a map sensor and is programmable with a laptop. It’s set up for around 17 degrees of advance at ~20psi. Runs 11.0’s like that.

BEFORE BLACK - About the 1982 GN

 

[edovigi]

The “before black” guy is Rich G.
He’s the fella to talk to. His 82 GN uses a carburetor on E85 and an HEI with an MSD box to control timing and pull back as it goes into boost. The MSD box has a map sensor and is programmable with a laptop. It’s set up for around 17 degrees of advance at ~20psi. Runs 11.0’s like that.

http://www.beforeblack.net/CantTouch.htm[/U

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[edovigi]

The “before black” guy is Rich G.
He’s the fella to talk to. His 82 GN uses a carburetor on E85 and an HEI with an MSD box to control timing and pull back as it goes into boost. The MSD box has a map sensor and is programmable with a laptop. It’s set up for around 17 degrees of advance at ~20psi. Runs 11.0’s like that.

BEFORE BLACK - About the 1982 GN

thanks for the info I'll try to reach out to him.

 

[b4black]

The 1979 did not use an ECM. 1981 was the first year for an ECM. (1978-1980 did use a Turbo Control Center - that was just for knock retard).

If you are using the 1981's computer, then the distributor should not have vacuum advance and weights. The 1981 distributor is control by the ECM and it is the same unit, turbo or NA.

I believe if you are using the 1979 turbo distributor without the Turbo Control Center, it just stays retarded all the time. That's why the non-turbo distributor is working better.

You'll have to go all 1979, or all 1981 for the engine management.

 

[edovigi]

appreciate the info.... I am using the 79 distributor with the turbo control unit which I suspect is my issue ..... do you see an issue running the stock distributor on my car less the turbo control system, I'm only running it at 7 psi boost using 92 octane fuel there is no noticeable knock or can you suggest an MSD ignition upgrade to manage the engine with easier available parts?

 

[edovigi]

The 1979 did not use an ECM. 1981 was the first year for an ECM. (1978-1980 did use a Turbo Control Center - that was just for knock retard).

If you are using the 1981's computer, then the distributor should not have vacuum advance and weights. The 1981 distributor is control by the ECM and it is the same unit, turbo or NA.

I believe if you are using the 1979 turbo distributor without the Turbo Control Center, it just stays retarded all the time. That's why the non-turbo distributor is working better.

You'll have to go all 1979, or all 1981 for the engine management.

appreciate the info.... I am using the 79 distributor with the turbo control unit which I suspect is my issue ..... do you see an issue running the stock distributor on my car less the turbo control system, I'm only running it at 7 psi boost using 92 octane fuel there is no noticeable knock or can you suggest an MSD ignition upgrade to manage the engine with easier available parts?

 

[BEATAV8]

You’ll need something in place to pull back timing when the boost comes on.
A regular N/A distributor with vac advance & weights typically runs up to 30-36 degrees of spark advance at high RPM. That’s way way way too much for even 7psi of non intercooled boost on 92 octane . Just to throw a target out there I’d say something around 18 degrees total in boost would be more appropriate. The MSD setup would be a good way to do it.

 

[b4black]

If you don't run the Turbo Control Center, you will have no Knock Retard protection. I avoid the knock issue by running E85. I run the MSD 6AL programmable. https://www.holley.com/products/ignition/ignition_boxes/street_and_strip/parts/6530

The 1979 Turbo Control Center when it hears knock, pulls a lot of timing and keeps it pulled for a long time. Same for the 1981/83 ECM systems. If you want to keep knock retard function, people recommend the J&S Safeguard. J&S Electronics SafeGuard Indivdual Cylinder Knock Control