Ok, a Nissan guy friend of mine claims that over in Japan they only have 97-100 octane and nothing lower. He swears my JDM P72 ECU that came with my 1998 GSR swap will be preset to run that grade and that I can't run anything but 97-100...wtf is what I have to say...your opinons guys...thanks in advance!

 

not really - octane just reduces knock - use premium with your GSR (91 octane here in cali, i mean my friends' USDM 00' Integra GSR says PREMIUM ONLY) and you'll be fine. what's missing from the JDM vs. USDM ecu is maps for emissions (evap purge control, etc.)

 

different rating system

we use R+N over here. They use just one of the letters, i forget which one.

 

91 octane is fine for the motor.. our 91 octane is Rated at like 98 in japan and Europe

 

Thanks guys...I love it that the emissions BS is missing on the JDM version...not used here in KY anyhow...no checks and all that jazz Pure catless screaming power