Factory ecu is getting old, main issue is knowing what does what, the values of components, and which way you need to go to change things. In short, dont bother, instead try bigger injectors, and combine with variable resistors in the afm temp circuit, and the water temp circuit to clip the pulse rates. They work on group fire, by altering/reducing pulse amount with bigger injectors you can sort of alter fuel delivery, combine with a decent camshaft, good exhaust system, they can be made to work ok. I have stumbles in mine at approx 4000 rpm, but above that to 7800 it is all good.
Other issue is the intake plenum flows different cfm air down each runner front to back, resulting in lean outs and burnt pistons. Intake needs to be airflowed and matched cfm per runner
A decent fuel pressure reg helps too.
Otherwise, just buy a aftermarket ecu,,,,,, i am selling a Autronic sm4, brand new, $2100
