Comptech-814

i tried to search this and i couldnt find anything maybe someone knows, there is a BP by me that has 101octane gas, if i put it in my car will it be ok, and is it worth the little extra to buy it?

CGTSX2004

iTrader: (1)

That much higher of an octane rating isn't going to do you a whole lot of good unless you're running heavy boost or a highly modified motor. For now, just stick to premium and you should be fine.

Comptech-814

i see i see, thank you

blueglows

yea but im sure its better than 93 just like 93 is better than 87 right?
Unless some one knows different that it can be bad for the engine...?

curls

Engines will not produce more power with higher octane.

Higher octane is required as a result of higher compression (or timing changes) that require better detonation resistance. Because of these changes in compression and/or timing, more power is made.

In the end, you'll be completely wasting your money with anything higher than 91. 93, maybe ok, depending on the quality of gas in your area and the use of ethanols, etc... but I stick w/ 91 Petro-Canada and won't change unless I boost, etc.

Brandon24pdx

As long as its unleaded race gas it wont hurt anything.

It would make a difference in some extreme cases. Drag racing in hot weather would likely cause the ECU to pull a little timing to compensate, even if you were using 91-93 to begin with. (especially true if you have a short-ram style intake that sucks in underhood air. Probably only worth it if you were going to the dragstrip for times.

BananaFusion

I still haven't found a station that has 91 octane gas. It's always 87, 89, and 93. With 10 cents between the price of each.

PittIsIt

BananaHammock -- try Sunoco

CGTSX2004

iTrader: (1)

Octane ratings will vary from station to station, brand to brand, but 93 octane seems to be the standard on the East Coast while 91 seems to be more the typical octane on the East Coast, but I have seem exceptions all over the place.

subdued

fixed.

subdued

yep: on the other coast: Northern California is 91 octane . My recent trip to Oregon allowed me to live it up with 93!

CGTSX2004

iTrader: (1)

Oops...didn't even notice that...I'm tired after a long day...

chuson

If you really want to try, try it. It won't hurt, and you can prove us all wrong as well.
Keep filling up 101 Octane fuel consecutively for at least 3 times, see any differences in butt dyno. Also check if your Fuel Mileage go up or down, and the differences in prices.

jlukja

Trophyhead

Octane available at the pump usually varies with altitude. The higher you are, the lower the octane. In Utah (4500 ft or so), our grades are 87 (reg), 89 (plus) and 91 (prem). There are exceptions, but this is generally how it goes. In higher altitudes (like Wyoming), regular is 85 octane.

Obviously, I haven't done a nationwide station-by-station poll, so there may be exceptions...as I'm sure several will point out.

I'm not a chemist or engineer, but I believe it has something to do with the density of the air and how much oxygen the engine gets out of the air to burn. At higher altitudes the air is less dense and that reduces the octane requirement for the engine. I'm sure there's a technical reason for it, I just don't know what it is.

SoCaliTrojan

In cali, we used to have 93 octane (or was it 92?) They changed it so now we can only have 91 octane.

Octane level basically just tells you how much harder it is for the fuel to combust/ignite. Imagine your TSX engine, with the piston compressing the air/fuel in the cylinder. With 91 octane, the fuel won't ignite until the spark plug ignites it. If you had 87 octane, the fuel might ignite on it's own during the compression (TSX is a high-compression engine).

The octane your car needs depends on how the manufacturer designed the engine. For example, honda accord's are designed to use 87 octane, and the TSX was designed to use 91 octane.

So now you know why you shouldn't use lower octane fuel than recommended. Now you might wonder if using higher octane is any better. Obviously, if the octane level is higher, you don't have any worries of pre-detonation (it'll ignite whenever the spark plugs ignite). Higher octanes supposedly have better additives/detergents, so that's a plus. The second is that it allows the car's ECU to adjust the timing (ie: advance/retard timing).

EDIT: To answer the original question, it won't hurt your car, but it won't help your car (much)

Mokijoki

I thought there was an octaine discussion on this forum before... Don't remember and too lazy to search... In most of europe we have 91, 95, 98 and in some cases 100 octaine fuels... I always used to drive on 95 octane, but since about 1,5 years have been driving on BP Ultimate (don't know if they use the same name in USA), which is 98 octane. Can't really say there is a major performance increase (maybe slightly better pull), but I definatly have better milage...

curls

What calculation is your octane rating based on? I believe ours in North America is something like (R+M)/2

The calculation makes a difference.

CGTSX2004

iTrader: (1)

I believe that European octane ratings are based on a slightly different system than the US system.

Mokijoki

I believe you are right.... we use a different formula then the (RON+MON)/2 used in the USA... Found this site in Google... guess it's the same fuel as the BP Ultimate (98) sold here... if so it's 93 (USA) octane fuel... I can say the promised better fuel efficiency is true...

BP Amoco Ultimate