Octane requirements for JDM
 

Hey guys,

I did some searching but couldn't find anything solid. I was wondering if anyone knows what the Octane or RON requirement is for JDM/99 spec cars is. My car doesn't have a sticker on the back side of the gas tank lid

Any help is appreciated!

98 RON. Roughly equivalent to US spec 93. Basically, the highest rated normal pump fuel you could locate.

Great to hear. 94 is readily available in my area. I was concerned it might be 100 RON and I would need to purchase an aftermarket ecu and tune it ASAP

Is the 94 E15 by any chance? That would not work well if that is the case.

It's ethanol free thankfully. Some other gas stations have 91 ethanol free as well

Perfect!

Ethanol-free is a dream here in California...don’t even ask about 94 octane. :-/

I guess I should be thankful for the gas in British Columbia... except for the fact that our premium gas works out to be over $6 a gallon 😂

91 Octane in my FD for the past 12 years with no problems.

This is with the JDM ECU?

Stock JDM ECU for the first 1.5 years, until there was a coolant seal failure that forced me to rebuild the engine. I went to a Power FC after that and raised boost pressure to about 13-14psi while still using 91 octane.