Anybody wth an M20 525i...

[CharlesAFerg]

Do any of you fill your car with anything other than regular grade gasoline?

[DaveVoorhis]

Do any of you fill your car with anything other than regular grade gasoline?

Nope. Here in the UK, I use regular grade petrol which is 95 RON.

[HIe34]

92 here. Local mechanic told me where i can get some 102. About $7 a gallon but worth a couple of gallons just to see.

[Mewsy]

and have found absolutely no difference in performance or milage with any of them. There recently was a report done here in Aus that came up with an average result of no difference between the three fuels in regards to milage and performance. I think everyone has their own opinion on each fuel, and some believe their engine's life is extended using the premium fuels. Each to their own!!

[Alan_525i]

Deep down inside, I figure it makes no difference. Even though the M20 doesn't have knock sensors, you'd have to have a ton of carbon build up to induce knock.

Despite the fact that I know it makes no difference, for the extra 4 bucks a week it might cost me, I let my irrational side sleep easier at night and fill with premium. I'll do without a Starbucks one day a week to offset the cost.(It'd be nice if it was only like 1.50 difference a week like it was a few years ago).

[joshua43214]

I run premium, my car is just not happy on regular. Price sucks.

[Zeuk in Oz]

Do any of you fill your car with anything other than regular grade gasoline?
I use high octane (98 RON in Oz) because it is supposed to have injector cleaners etc in it.

For the little extra cost it gives peace of mind - possibly not worth it though.

[M20Turbo]

My M20 likes the high octane. Which here in New Mevico at 5200ft. is 91 octane. I will run 101 octane from time to time at $4:25 a gallon.

[Jon K]

Any boosted engine will essentially "require" highest street octane available. A stock M20 or even a modded but un-chipped and stock compression motor should still run regular... there's nothing to be had by adding higher octane if there is no timing map to take advantage of it.

[525i!]

Do any of you fill your car with anything other than regular grade gasoline?


ok this is where my schooling comes into use. so IT DOSENT MATTER. if your car runs on 89 then run it on 89. running it on 104 does you no good, it dosent do bad but still no good either. if you want good gas with all the detergents and **** in it you have to go to a exxon or mobile GS. besides that running I high octain fuel in your car is just a waste of money unless your car needs it. all the high tess fuel does is burn a little slower very good for high comp and booster engines but pointless for a unmodified engine.

[CharlesAFerg]

oops

[CharlesAFerg]

I saw some old people filling up their chrystler something (old people car, I don't even remember) with rpemium, I'm beginning to think that people thing premium is better for the engine because it's called premium... The only car I get premium for is the family's Porsche 928s They are picky, because it was built for it. I was just curious if the E34 was built for higher octane, but i figured not, just thought I would check! :D
Thanks guys

[TheEndIsNear]

The book for my '90 says regular is fine but I run 3 out of 5 tanks premium. I never notice much difference in power or mileage but I do get slightly more tick on the regular.

[SC David]

My car runs noticeably worse with regular. Idle will be rough and there is a loss of power. My girlfriend's E30 M20 runs smoothly with regular though. Meh.

[TheEndIsNear]

I really think it just depends on how beat the motor is and how honest the gas station is...

[BillionPa]

any car with a "performance chip" should require high octane gas, because the performance chips mainly change the timing advancement maps.

however, running high octane on a car that is listed for low octane can actually cause problems, because octane is the resistance to ignition (and preignition), and having the gas ignite at a different speed is bad, mkay

[TheEndIsNear]

Well said... My protege always ran better on regular.