M20 Octane question

[german g]

What octane do you use in your M20? 87, 89, 91, 93?
Or ,what are you supposed to use in a stock M20??

[mrsleeve]

my car like mid grade or better, pings like a bitch with regular

[german g]

im getting told on bimmerforums that 93 will damage a stock M20...is this true???

[fretburnr]

im getting told on bimmerforums that 93 will damage a stock M20...is this true???

Thats bullshit. higher octane rating only represents a fuel's resistance to knocking.

can't speak for cheap quality fuels though, watered down etc. someone may be using crap gas and claming its the octane thats causing problems.

i run Mobil or BP or Shell 93 octane ALL the time, and my m20 is stock except for a chip.

[german g]

Thats bullshit. higher octane rating only represents a fuel's resistance to knocking.

can't speak for cheap quality fuels though, watered down etc. someone may be using crap gas and claming its the octane thats causing problems.

i run Mobil or BP or Shell 93 octane ALL the time, and my m20 is stock except for a chip.

DIG, thats what I thought..93 is all i use in my m20..

[Sean]

Why would high octane DAMAGE a motor?

Only thing I can think of is that it wouldn't detonate correctly because the octane would be so high. But, why would you run 93 on a stock M20 anyway? A stock m20 runs on 87, you only need 91 or 93 if you're running a chip?

Ok, good - so I'm not the only one that thinks that's retarded.

BF is funny.

[Digitalwave]

DIG, thats what I thought..93 is all i use in my m20..

Do you have a chip? If not, you are wasting your money.

I have been running 89 octane with a chip in my car designed for 91 and I haven't had any pinging. 87 is fine for a non-chipped car.

[german g]

damn, looksl ike ive been wasting my $$ lol, oh well, i have a 93 chip in the mail.

[Sean]

I'm running 91 in my stroker. But...I'm breaking it in and want good fuel. heh

[X2theZ3]

Thats bullshit. higher octane rating only represents a fuel's resistance to knocking.

I always tell people this and then they try to explain to me how the fuel burns slower and will not completey combust which is bad for the car and all this other bs. So i've given up.

[IS]

I'm running 91 in my stroker. But...I'm breaking it in and want good fuel. heh

That is illogical.

A stock e30 is mapped to run on 87 octane gas. The only result with higher octane is a lighter wallet.

Higher octane fuel is harder to ignite and may even not burn completely. This is a fact. Running higher octane on a stock e30 only has potential to decrease performance, and can cause additional carbon buildup.

[german g]

That is illogical.

A stock e30 is mapped to run on 87 octane gas. The only result with higher octane is a lighter wallet.

Higher octane fuel is harder to ignite and may even not burn completely. This is a fact. Running higher octane on a stock e30 only has potential to decrease performance, and can cause additional carbon buildup.

thanks, that makes more sense..

[X2theZ3]

That is illogical.

A stock e30 is mapped to run on 87 octane gas. The only result with higher octane is a lighter wallet.

Higher octane fuel is harder to ignite and may even not burn completely. This is a fact.

Where's the proof of this "fact".

I'm still not convinced of this statement "Higher octane fuel is harder to ignite." I think it should be Higher octane fuel is harder to PRE-ignite. Once the fuel ignites (like it's designed to) by the spark plugs then it combusts the same as whether it's 91 or 87.

[MR 325]

87 is just fine for stock M20's.

I run 91 in mine of course, we don't have 93 here in Cali. :)

[AdironRider]

Running 93 octane is no worse or better for an m20 than 87. Running 93 isnt going to increase carbon buildup either.

I run 93 in my chipped m42 exclusively, most of the time Sunoco. Sunoco has never given shitty gas, which I cant say for Mobil, Citgo, et all. Usually pretty good prices as well on all grades.

I ran 87 only in my 325is as well as my 325ix, they both loved it with solid performance and decent gas milage.