Always use premium gas.
I only use Sunoco 94. Unless I'm away from home and can't get it...then, Mobil 93. Only the best, it does make a difference.

 

Octane rating is a fuel's direct ability to resist pre-ignition. (also known as pinging, spark knock, detonation, pre-burn). With the S2000's 11.0:1 compression ratio, I wouldn't even think about anything less than 92 octane. Even for an engine knock sensor to compensate for spark knock, it must first detect it's presence.(maybe someone could post a pic of a piston exposed to prolonged pre-ignition) that should clear the air. Kekoa; every station i've seen sells 93.(ny,nj,nh,vt) may have to do with CA strict emissions reg.

 

I put 5 gallons of the cheap stuff in while in St Louis on an empty tank. It was interesting, the car ran but would not engage VTEC -- or maybe I was just imaging things....

 

It is safe to use regular gas on the occasion. The ECU will retard timing to account for the lower octaine (prevent predetonation). You will notice a reduction in power, increased engine noise, rougher idle etc...this is a safety percaution built into many cars that require Premium....

If you really need to, and Premium gas is not available then u can use Regular....but dont make it a habit. The S2k ECU/Engine is tuned for 91 octaine gas.

My reccomendation is to use 91 or higher. You will get the best performance and longevity from your engine.

Good Luck

 

Over here we have the choice between 95 and 98 octane, the manual states to use minimum 95 octane for the F20C1 and 98 for the F20C2 engine (mine is F20C2), it also states you can use lower if it is not available and if no detonation is caused

Does anybody know the difference between F20C1 and F20C2 ??

Is the US engine different (ECU settings) as it can run on such low octane fuels without problems ??

 

sunnoco's 94 is THAT much better than mobils' 93?
i always use mobile... should i switch?

 

Hi,

we checked the difference between taking a 95-octane-,98-octane- and 99-octane-fuel in the German club scene. There are two major differences. Using the 95-octane-fuel brings you to up to 13-14 liters for 100 km consumption and the 99-octane reduces to 10 liters/100 km. The other difference is the power. Driving the 95-octane-fuel you may recognize a massive lack of horsepower instead of using the High-Octane-Fuel.

>>So I wonder if the US-Model with a filling of 91-octane-fuel gains as much horsepower the a European model with 99-octane-fuel ????

Peter mit 180

 

Yes, the 11 to 1 compression has higher requirements than engines with lower compression ratios.

 

Why can't we get anything higher than 91 in So CAL!!!!

 

[QUOTE]Originally posted by QuickS2ilver
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