[FRSBRZGT86FAN]

Originally Posted by CatScan

I'm still waiting for reports of an FR-S/BRZ damaged by using lower octane "every now and then". Are these cars only sold in areas that have 91 or better? Or is it that the possibility of running lower octane if needed was taken into account when they built the thing.

Whatever, I guess.

Originally Posted by CatScan

Ahh. Perhaps number-one son could find a YouTube video or someone could text him. No doubt the owners manual is waaaaay too big with too many words to even open.

I forget that people take advice from the www instead of an actual, factual source.

My car runs great on Alphadelic IPA. You guys should try it.

Originally Posted by CatScan

RTFM must be an age thing at well. It would never occur to me to not read the owners manual. Regardless, putting anything less than unicorn pee in your car every now and then if you have to will not cause you any problems.

Originally Posted by CatScan

No shit on the tune, that's fairly obvious. And a tank of something less than 91 octane won't kill your car. Got any proof of how bad that is? List of dead cars? Class-action suit?

Don't ever go to Colorado, I guess, where up in the hills you might find yourself stuck with 85 octane gas. The horror!

Originally Posted by CatScan

Or 87 if you have to. You wont hurt the car. E85 is the best solution though.

Originally Posted by CatScan

Perhaps I am not speaking English. Are you saying the ECU can not (or was not) programmed to handle sub-optimal fuel?

Originally Posted by CatScan

Again, you translate what I am trying to say into something understandable, thanks.

Let me try: To think that Toyota/Subaru designed this car WITHOUT considering that at some point some of them will HAVE to run on low-octane gas "every now and then" is idiotic. That's what the ECU is for.

Then again, I'm ASSuming that the typical owner of a car will read the manual and understand what's going on.

Dude you're attacking everyone with fallacies This is what the manual says for posterity as these type of threads continually keep popping up and no one bothers to either do a search before posting or simply look at the quick start up guide or manual of the car and it's quite sad.



In layman terms use 93 AKI/98 RON or higher, if you don't have that available you may use 91 but only if the higher grades are unavailable


It does not mention 87 however, the assumption can be made the highest available average octane is 91 (U.S. and candian AKI I think canada uses it not sure) or 95 RON in other places.

If you do put 87 you have to understand you're taking a longevity risk, why? Every time the car has to alter it's IAM (Ignition Advance Modifier) below 1 or that means knock is being detected and it is having to adjust to try and prevent another "knock event" (not sure if that's the right term @steve99 knows his stuff about this ), once the IAM reaches 0 you're out of luck the ecu can no longer adjust timing to counter the lower octane fuel and knock will happen consistently. Every time this pre-detonation knock occurs you put a lot of stress on parts specifically the valves, piston head, and rods, ESPECIALLY in an engine with as high compression as this where they have a tendency to knock on lower fuel like 87 because with lower octanes it is more likely to ignite. Now putting 87 in a full tank once or twice is no big deal but if you keep doing it to save a few bucks or because you think you know what your doing you're creating unnecessary wear long term to the engine.

This isn't a new concept to engines or sports car, in fact a Shelby GT500 from 2007-2010 didn't even come with a knock sensor and doing something irresponsible like putting fuel under 91 would probably kill the car in a few highway runs. I don't understand why you're making a big deal when everyone is telling you you're wrong, including the manual and science. Find something of hard tangible evidence to prove us wrong.