'87 350 TPI GTA modded. I was going to add an ATI procharger next year and I do make my own chips. Can anyone tell what needs to be altered in the prom settings, ie.MAF tables, when installing a supercharger.

The engine is already modified to accomodate a SC so I'm only interested in the PROM settings needed to run a SC.

Thanks,
Chris

 

So are you planning on using the FMU or modding a stock ECM and PROM to control fuel under boost?

 

I am not planning on running a FMU. I am also running the Crane HI-6S which has boost retard capabilities.

 

S/C, and T/C put alot of heat into the intake charge when they compress the air to make boost. The 3rd Gen MAF system doesn't allow for ANY corrections for timing or fuel due to charge temp increases. So you wind up having to run the timing at worse case scenario settings.

Lots of threads here about the 749 which is what GM used in the Turbo charged Syclones. It has the proper tables, and code to deal with boost.

 

7749 :lala:

 

Does that mean another ECM or just a different bin?? Also, does this mean that with the 165 ecm I have to run the timing backed down a lot or is it just advantageous to convert to the 749???

Also, If I did run a FMU would it prevent me changing the ecm over to the 749??

 

It's a different ecm. One that was designed to run with a 2 bar map sensor. The code is better (my opinion) than the 165 as grumpy has pointed out countless times.