just put a p28 ecu on my GSR motor because i'm installing the skunk manifold this weekend. i got one of the mugen style chips (redline 9k, vtec-5800) me and a friend installed the chip. its about the 5th time we've chipped an ecu sucessfully. chip works exactly like its suppose to. only problem, my A/F gauge is staying on rich, only time it goes to stoich is when i gear down, but while i'm driving it stays rich. i've adjusted my fuel psi from 40 to 50 and everywhere in between, still rich. no gas or any liquid coming from exhaust, doesn't smell rich either. i'm thinkin its probably ok but i had to ask just in case.