quick question

The lowest octane around here is 87, which is what i think most stock cars are recommended to use. 91 and up octane should really only be used if your car is tuned/high compression/heavily modded for it, it won't "hurt" to use it on a stock car but it also won't gain you anything using a higher octane, in the end it actually might sap a small amount of power from you.

ya cuz in colorado its unleaded 85 super unleaded 87 and premium unleaded 91

Stick with 85 or 87 if your car isn't heavily modded or don't have your car tuned for higher octane. The higher the octane means it has more of a resistance to ignite (yeah i know it sounds backwards but its true). They are used in high compression engines to prevent premature ignition or pinging.

ok well can i put in 87 in my car now even though i have been using 85 for along time now

Yeah, if you don't care about the extra few cents/gallon, it wont hurt. I wouldn't go any higher than 87 though.

ok cuz im on e right now and will b puttin 87 in tomorrow will there b a difference

I think 85 and 87 should be almost exactly the same in performance. Its not until you get into the higher octane 89-93 where you would actually lose performance in your lower compression engine.

just put the 87 in your car. you wont really gain anything for going with anything else IF you dont have a performance tune.

Ok thanks guys ya I'm not heavily modded so ill b good then I just don't understand the difference if its 85 and 87 besides the price lol

damn those octanes are low, we got 93 octane and there is a gas station around me selling racing octane, i think its 97 octane or something ridiculous

Yeah i've never seen 85. Its 87 89 91 93 around here. And yeah racing fuel is like 97 or 100 octane. And sickstang. The difference between the octanes is the higher the octane the higher the resistance it has to ignite. So in higher compression engines low octane can actually ignite before the spark due to the higher pressure in the cylinder which is called a "ping" because it can make a ping sound. So higher octane is used in these types of engines so they can take advantage of the higher pressure which produces a more powerful explosion aka more HP.

Octane at the pump usually goes down a little when you go uphigher altitudes, and also for some reason California has 91 as the highest widely available octane. There are a few (very, very, VERY few) pumps with higher octane, but theyre hard to find and usually out of the way.

Ok then ill switch to 87 then until I do more things to my car

it doesn't ever hurt to run higher octane gasonline, unless you run really high octane in a stock tuned vehicle.

Run 87 in it