I have a series 4 rx7 and I am deciding whether or not to get a microtech ecu installed. I have a 3' exhaust and pod intake. Spoken to the 'experts' and they say its only a matter of time before the engine will blow cause it is running lean.

Main question: will I get significant power gains from a stand alone ecu with the engine fully tuned (ie fuel mapping etc..)

And.... how much boost would be safe(reliable) on a standard series 4 engine? (with a ecu)

 

I was going to answer your main question but thought that there are better people to do that

with a 3" exhaust and intake, safe boost for a bone stock series 4 (non-ported wastegate) should be 10psi

but without a ported wastegate, you are in dangerous territory for boost spike/popped engines