hey guys

i am about to turbo my engine... a gslse engine... and i was told by a friend that knows alot about cars that i should only have to run 89 octane, cuz since my engine is already high compression thats all it should need, and he said that i shouldnt need to run 94 oct... what do you guys think? cuz i dont know... if i can run 89 or 87 then AWESOME... lol save me money... if not so be it... just let me know... thanks!

 

Generally the higher the compression, the higher the octane required. A non-aspirated rotary engine (13B) runs better on low octane fuel and premium is not recommended to my knowledge. Why don't you experiment and find out what works best? Just run the tank down and fill up say 1/4 full and give it a whirl. If your worried about the incremental cost of fuel then why are you blowing $ on converting your engine to turbo in the first place. Just my $0.02.

 

If you are going to turbo your engine I would suggest that you run a higher octane. The reason for this is detonation. Detonation can/will be fatal to your engine. Many people flamed me for it but I used to always put 92 octane in my SE.

Ask the turbo guys, all that care about the life of their engine will tell you they run 92 or higher.

~Z

 

ok i understand the part where it reduces detonation but... since its a higher compression engine already... and normally a turbo jadds compression to a lower compression engine, thats why they run it... but like i said since its already a high compression should i only run one grade higher?

and how do you know if you are detonating... like are they're any kinda sounds or vibrations ect that i need to listen/ feel for?

thanks
Cory

 

Run premium, until you can get it on a dyno with a knock sensor and wideband. Dyno tuning will tell you what your afr's are and if you are getting any knock.

If you can hear the detonation, it is sometimes too late for the engine. Don't take the chance.

 

the higher the octane the higher resistance of detonation (pre explode b4 ignition lights it off) so with higher compression the lower gases resistance to detonate starts to go away.

and P.S your friend that knows alot about cars is a moron. even if a car already is high compression a turbo will make it even higher run 92 or blow up your engine.

 

^ i'm with him, usually, the higher the compression ratio, the higher the octane you want to run. the exception being n/a rotaries, but anything supercharged or turbocharged, the higher the better.

 

In any turbo application, I'd run the highest octane fuel available. End of story. The risk of detonation in a rotary is too grave to do anything else.

 

i allways put 92 in my tank......If they had higher a the local gas stations i would buy it.....
I Dont want to POP my motor!