The 91-93 Syclone/Typhoon PCM?

The world may never know.......

 

Now that I think about it , I dont know why. I know there computers can read boost but I didnt know the two pcm's were compatible?.

 

They can be configured to run on a 4, 6 or 8 cylinder car. Other than that, probably not too much work adapting it to a newer car. If the VSS is not the same, well they will accept a magnetic pickup VSS.

I'll be adapting one to a 72 straight 6 car, I'm finding that other people elsewhere are using them on totally foreign cars, so I dont see why people here are not more creative, and instead crying about thier $2500 computer requirements.

 

Doc,

I think the hang up would be the optispark control. I've used the 730 ECM on a BBC with no problems and I'll be running the SY TY 749 ECM on a blown olds. Both are using GM HEI ignition.

Steve

 

what ever happened to this?

 

Good question. I've heard from many that it has been done, but never found specific details for lt1's. Only TPI stuff...

http://www.speedtoys.com/~bort62/7749/Main.htm

 

Bingo

optispark controls.

I think your best bet woudl be tuning the stock computer. If you wanted to get fancy then you can try to piggyback a 749 on a stock computer.

 

Well, my desire is to get a car that doesnt need a complete re-tune every time I adjust boost. I would prefer a low boost setting for the street, and a high boost setting when I feel frisky. Now I know I CAN use an Apexi S-AFC, but that'd be a lot of effort to get the adjustments down correctly - and that doesnt solve one safety issue turbo guys have. If you get Boost creep and dont realize it instantly - how do you account for the extra air once your maf is maxed out?

You go DFI or fast. If removing the opti spark is part of the solution (which many of us would prefer anyway) and going to a crank trigger or the like, couldnt that still be an advantage?

I know far too little about piggy-backing ECU's.

 

For LT1 owners, there is a very easy answer to that ... the 749 requires the signal from a late model GM HEI distributor =! high/low signals from the opti. You could machine your LT1 intake for a conventional distributor and go through wiring hell to install the 749 (while retaining your stock pcm around to keep the guage cluster/ect alive). Seems like a pain. A LOT of 3rd gen guys are doing the 749 swap - the pinouts are almost identical.

 

With the 749 you would also have to remove your MAF and switch to speed density. Not really a big drawback in my book, but it certainly adds to tuning time. Also, AFAIK, the 749 can not handle EGR controls when set to run a V8.


Steve