I have a question on how much boost I can safely tune for / get away with so here is the setup
93 hatch
F20b w stock internals
660 siemens deka injectors
chipped p28 on crome
turbo out of a stock Vr4 3000gt

also, my "boost tools" plugins dont work on the p28 base in crome but they do work in the p30 basemap, if I use the p30 basemap can I put that chip in my p28?

 

There are too many variables for us to give you a "safe psi".
You could be running x octane with an x sized exhaust/down pipe, with an x sized intercooler & x style turbo manifold that flows like crap etc...

Concerning crome. Yes you can use p30 code on a p28 ecu.

 

nice reply....MY question is are you tuning this? Because you should know what PSI you can go to if you are. It really depends on the injectors and what you wideband says

 

I would post this on pgmfi.org forum. If you tune on crome and your not on that forum, your lost

 

sorry in order: 91, 2.5 staight out, 60x30x7.6cm, fabbed a ramhorn out of schd. 80 fittings. this is just a dd with a street tune. Im not shooting for huge numbers here just a low 300 would be nice. I guess my main question was that with the stock 11:1 pistons how far can I push this. is 300+ realistic or do I need to go back and redo the bottom end?