What GAS grade ?

[m3f_AngelsToy]

i hope everyone has deep pockets. gas will be 5.00 Very soon, if not already for your "crappy" 87. heh. honestly, with all the gas hype, do you think you're getting what you pay for anyways? maybe.. maybe not.



oh btw. has anyone tried that "not street legal" octane booster from AutoZone? i forgot the actual name of it but it says it's not legal for street use and it's a pure octane booster, not a cleaner.. anyways, i ran my beemer almost dry(i know it's not good. get over it), put that octane booster in, and then filled up half a tank of 93. it said it treats upto 20gal. so i figured 8 gal .. less gas = more octane?!.. well i noticed a differnce and i had a little more pep in my step for a couple days. fun times.



-mike

[m3f_bigneil_f35a8c7058]

I've only used Premium (8 years, 134,000 miles) and the engine rocks, and always has. Why take a chance? Plus, it's always 20 cents higher. When gas was $1.00 per gallon, that was 20% more. Now at $3.00 per gallon, it's only 7% more.

[m3f_Bell]

I asked the same question on a miata board and I got an excellent technical responce. It kind of sums up a lot of the posts here...



Octane is a meausre of a fuel's resistance to pre-ignition. As fuel is compressed in a cylinder by the piston, the temperature of that fuel rises pretty much directly with pressure (thanks to the Ideal Gas Law). All fuels will ignite without need of a spark once they reach a certain temperature. Ignition of the fuel in a cylinder is a very controlled event, and pre-ignition, or ignition before the spark plug actually sparks, does all kinds of nasty things to the components in your engine, in addition to decreasing the power output of each combustion cycle.



Engine manufacturers design their engine duty cycles, spark plug ignition times, spark power, compression ratio, etc., based on an expected amount of octane. If you have fuel with too low an octane rating, it can pre-ignite. This pre-ignition is basically like having uncontrolled explosives going off in your combustion chambers, which puts enormous stress on engine components.



Conversely, putting in higher than required octane doesn't actually benefit you, nor will it increase your engine's power output (unless your car's ECM can electronically advance the spark timing and measure detonation events with knock sensors). In fact, it can cause damage, because higher octance fuel is actually harder to burn, leading to more unburned fuel in the exhaust, which raises emissions, actually robs power (less complete combustion in each power cycle), and shortens catalytic converter life, among other things.



So the question I have is, anyone have an owner's manual in front of them? Does it recommend an octane level and if so what is it?

[m3f_fple6]

You guys are making me cry! 87 octane is $3.15 in Champaign, Il. Bend me over again.

[m3f_98M3and325_d8d2e42902]

You guys are making me cry! 87 octane is $3.15 in Champaign, Il. Bend me over again.



$3.15 in Champaign for 87? Man, that's more than out here in the Chicago burbs. I just filled-up today with BP Ultimate for $2.99. I graduated from U of I by the way about a decade ago.



Jinya, did you ever end up by an M?

[m3f_Jinya1004]

$3.15 in Champaign for 87? Man, that's more than out here in the Chicago burbs. I just filled-up today with BP Ultimate for $2.99. I graduated from U of I by the way about a decade ago.



Jinya, did you ever end up by an M?



YES I did, and I'm a happy boy.



I saw some price of $3.50 now for gas.



I'm thinking of keeping my Civic now. I was going to sell it and buy toys for my M3 but maybe I'll drive it and save some money.

[m3f_m3parker]

with the shortatge down in the southeast, i paid $3.39 the other night :banghead:



hopefully the pipe lines with have restored power by next week

[m3f_AngelsToy]

hey, i don't know if any of you know this or not but you can check gas prices online for any area..

http://autos.msn.com/everyday/everyday.aspx?src=LeftNav

either enter your zip code on the right or click Gas Prices on the left menu to goto the map where you can select metro areas.. like NYC and miami.

they might not have all gas stations but it gives you a general idea of what your area is priced around..