jeff_man

So by my hosue there is a place selling 93 for about 1-3c more then every one else selling 91 and was wonding if there was any true diffrens in a s4 13bt w/ a s5 turbo while using 2 stroke premix stuff.

Icemark

well remember that pre-mix lowers the octane levels

But anything above 87 is a waste of money if the car will run without knocking or issues.

Remember the octane rating has absolutly nothing to do with how many BTUs can be generated, but rather the higher the octane number, the more resistant to exploding/burning.

jeff_man

ya but i wouldn't run a tII with 87 oc =P

Icemark

if it runs without knocking or other problems at the factory spec octane (87) why would you waste money on a higher octane???

Innovation

iTrader: (1)

A bunch of people I know think that they are doing their car a favor by adding high octane fuel because of all the stupid gas commercials. I'm sure after paying 3 to 4 bucks a gallon all those dumbasses have settled with 87 octane they could have used in the first place!

Icemark

well actually on a rotary engine, using too high of an octane will result in build up in the engine.

Remember the higher octane resists exploding/burning, so if you run too high of a octane you can actually have gas not burning and instead coating the rotor's face and slow burning there (leading to carbon and gunk build up) instead of as a gas.

jeff_man

ok then no oc 93, i'll stick with 91 then

slpin

iTrader: (9)

i run 87 on both my t2... 87 and 91

what mods do you have in your car, jeff?

jeff_man

Front Mount Intercooler, 255 Fuel Pump, RB 3" catback system, FD Corner Seal Springs and all new seals, S4 Block W/ S5 Turbo running 10psi, Block Off Egr,bac,omp, FCD, Hks Ssq Blow Off