Honda Car Forum

do you have to use the premium 91 octane here in NorCal gas in preludes or is it recommended or you can use regular 89 Octane what is the deal i know my 1993 Nissan 240sx said on fuel cap premium 91 octane gas recommended but i always used 89 octane

just becuz its recommended doesnt mean u have to stick with it. some of my friends here i am from nor cal and they own some ludes. some guys use 89 while others who have some crazy fast ludes use the 91 octane

it all depends on if ur engine pings when u have the lower octane in. if it does the use the higher octane. i am from nor-cal also and i had that same problem with a car of mine. so i have to use premium on it. at 3.70 a gallon it blows.

Not manditory but, when you take the car for inspection, make sure the 2 tanks of gas before inspection are 91 or higher... It'll help to make the car pass emissions tests..... Other than that, 87, 89 or 91 are all fine....

i have a mitsubishi ecilpse 98' turbo and when i first bought it i ran 93 in the thing and then i switch to 87 and once a month i'd put 93 in it. Putting 87 in or 89 should make it run any worse as long as you run 93 in it once and a while to clean the carbon out. When they say recommened it's just what they mean. It's not going to hurt it.

it all depends on your compression ratio cars that require lower octane can run the higher octane but it will not do them any good. cars that require the higher octane may run rough, pin, or knock if this happens go back to the higher octane fuel. because the lower octane fuel will ruin you motor over time. Try it for yourself but I would trust your owners manual the people how built the car usually know what they are talking about

ur time and look at that video, it shows what the difference when it comes to octane preference.

I also own a 2001 Honda Prelude and would rather die than put anything less than 93 octane in it. I guess up there in Northern California all you get is 91, but that's ok too. Your motor, the H22A4, has a pretty high compression ratio compared to most cars. That's how it's able to make just short of 100hp/Liter. Your 240SX sadly enough uses a KA24DE motor that's probably better suited for a compact truck than a sporty car. Not a really screamer of a motor, 89 would be great in a car like that. If you intend on driving your Prelude with any sort of vigor, or you would like to "haul ass" if you will, I'd stick with the 91 octane you use now. You run the risk of detonation at high engine speeds with the lesser fuel though. So if you were to use the 89 muck then you should try to keep your engine speeds (RPMs) down, and stay outta VTEC!