Any fuel reccomendations for '90 E30?

[Yesterday617]

I've been putting in plain 87 octane. Is there any reason to use a different type?

Also, how about oil. 130k miles 6cyl manual. Changing this weekend.

 

[Big Daddy]

If it was mine I would use minimum 91 octane, but I am not sure that is required or recommended with the 90 models. If you have no oil leaks than I would use 10-30 in a synthetic oil, such as Mobil 1.

 

[epj3]

Use 89 - BMW requires 87 or higher for the 6 cylinders, using 91 could possibly have a noticeable DECREASE in power. The 6 cylinder motors are fairly low compression, so high octane is unnecessary anyways. I did however notice the engine smooth out quite a bit using 89 instead of 87 - probably becuase the motor had 182k miles on it.

I know using 92 in my E30 had a noticeable decrease in mid and high rpm power. Big daddy is right on about the oil, for a 130k mile E30, synthetic would be ideal.

 

[otahand]

BigDaddy,

Why synthetic oil if NO oil leaks? Just had the head gasket kit installed on my 1991 318i with 67K. Was leaking oil badly from the head and edge of profile gasket on top of the timing case. Now I am running synthetic BMW 5W-30. It's been a couple of weeks, and it's dry as a camel's #%@.

 

[AutoXfreak]

I have had just the opposite luck with the 91 vs. 87. In one instance my mom drove my car for a week and when she returned it I noticed there was a drop in power, turns out she put regular 87 in the tank and not premium. This was before my car was chiped too. Oh thats another point. If you plan on chipping your car youll have to run premium or the engine will preignite (bad!!!).

 

[Big Daddy]

I ran 91 in my 91 318is as that is what it called for.

Why synthetic oil if NO oil leaks?

Because if you put synthetic in a leaking car you are wasting and leaking $4.00 a quart oil. Fix the leaks and than fill with a synthetic.

 

[1985_318i]

Just my two cents but Royal Purple is much better than Mobil 1 as I have used both. All the claims that they make about gaining more power and better mileage is true. My first experience was in my 1987 Nissan Sentra. I changed from Mobil 1 to RP and went from 30mpg to 33mpg, it revved quicker, and felt stronger. (It's not in my 318i b/c my dad gave me 5 qts of Mobil 1 15w-50)

 

[Big Daddy]

I highly doubt that switching from a carbon based synthetic like Mobil 1 to Royal Purple would result in a 3 mpg gain. I am sure that there must have been some other factors involved, climate, driving habits, etc. I would believe a 3 mpg gain from Dino to any Synthetic. That said I have owned a dozen or more vehicles all raised on Mobil 1 with no complaints or adverse affects, and a few sold with in excess of 250k. I wonder if your Sentra had been running on synthetics from birth? That could make a difference. I am sure that RP is a high quality synthetic, but than again so is Mobil 1, Red Line, etc.

 

[1985_318i]

I agree completely, and I should have said it went from 15-50 Mobil to 10-30 RP (sorry

 

[hatchman088]

I use 89 because everywhere around here goes 87 89 and 94... its all screwed up