I have a question that I didn't see answered in the "read this first" stuff.

I have an 86 Iroc. As far as I know, the ECM and PROM are factory.

How much will this computer setup restrict my ability to increase HP and tq? for example, if I swap in a 350 crate motor, will the car need a new computer so the 350 can perform properly? Or, will the computer still consider it my 305 tpi and essentially keep power as it was before as if no new motor had been installed? Just wondering at what point I need to consider a new PROM if I'm trying to squeeze out more HP.

thanks.

 

The factory ECMs can handle a LOT. GM put a ton of money into developing them, and the aftermarket stuff is just now catching up to what GM put in these cars 15 years ago. The ECM is not a restriction at all for anything less than a full-on trailer-queen drag car.

The calibration is a different story. When you make a major change to the engine's characteristics (i.e. an engine swap, head work, intake upgrade, new cam, even just changing the exhaust) it changes what the engine wants. The more things you change, the farther off the calibration gets, until the car becomes undriveable or unreliable.

You should consider PROM tuning as one of the first things to do with a car, if you want to get the most out of it. That way, when you change something, you can adjust it so that the computer works WITH those changes, to maximize your gains.

 

thanks man, that's just the kind of information I was looking for. appreciate the feedback. time to start researching PROM tuning.