ok this is a dumb question i know, but i figured that i should get an anwser before i do it. OK so im getting my 04 priddy soon and was wondering what everyone thought about putting in a mixture of 100/92 in a stock motor. Im asking this
because i wasnt sure if running a high octain in a stock motor would do more harm then good sence its not f/I or nitroused. Thanks for your imput.

 

You want to run the absolute lowest octane possible without pinging. Lower octane fuels burn faster (more HP). 91 is optimal for the S2000. Anything more is a waste of money unless you reprogram the ECU to take advantage of it.

 

yep, this is what i've heard as well.

Benefit to higher octane gas is that it often has moredetergents and such, so it keeps the injectors and intake valves cleaner. I run premium every 3rd tank in my '92 accord, have done so for a long time. It seems to run harder with the high octane stuff, though i run it just for the cleaning effects. The S takes 91, so feed it 91.

Quick2k

 

 

Sorry Koala, but you're incorrect on this one for several reasons.

1. There is not a causal relationship between octane and burn speed. True, sometimes lower octanes burn faster, but it isn't a rule. A good 100 octane race fuel will usually have a quicker burn than a typical 91-93 octane consumer gasoline. Remember, octane is a measurement of resistance to ignition, not burn speed.

2. Racing gasolines are usually formulated with a far more consistent mixture. In comparison, typical consumer gasolines have a wide mix of heavy and light components which burn at different speeds, etc. This more consistent mixture can also improve performance.

3. The Honda ECU in the S2000 uses an unusual knock and ignition timing scheme whereby it is _always_ pulling out ignition timing through the knock sensor. Higher octane gas reduces the amount of timing pulled out in most cases.

You don't _need_ to run anything more than 91, but running higher octane has some useful benefits. The magnitude of those benefits may not be noticeable to the average butt though.

UL

 

UL is right, but it is also true that most oil companies provide higher level of detergents with their premium fuels. And octane is not the only thing for power - ethanol provides higher octane, but less power because its specific thermal output per CC of fuel is lower than gasoline without ethanol.

 

Thank you for correcting me. I was told what I [used] to believe by someone rather knowledgable.

What you're saying does make more logical sense. Thanks!

 

i really appreciate all the help everybody. I figured i should get all the info before jumping into anything thanks alot guys