e10 ethernol blends in old e30 323i

[nrubenstein]

One thing that continually causes confusion is that octane is measured differently in the US vs. most of the rest of the world. 87 AKI US regular is roughly equivalent to 91-92 RON in the rest of the world. Likewise, 93 AKI US premium is roughly comparable to 98 RON in the rest of the world.

[lentildude]

thanks for all the comments from everyone, many opinions. Thanks Madhatter for your local perspective/experience.

I have 1/2 tank of e10 (octane 91) left. Might fill the other half with either proper 95 or even thinking of high octane 97. The 97 might bring up the 1/2 tank of e10 to an average of 95?? Guessing mixing all these fuels isnt a good idea either.
(been getting crappy fuel economy on e10, about 6-8km/litre on highway)

BTW- Shell(Coles) e10 is 94. Is 94 close enough to the reqd 95 to run safely in the e30?
Caltex e10 (Woolworths) is octane 91

"Shell Unleaded E10 has a minimum 94 octane rating, much higher than the Federal Government mandated minimum of 91 octane for regular unleaded fuels. If your car requires a fuel with a minimum 95 octane rating, we recommend you use Shell Unleaded 95"

[Madhatter]

still, I'm fairly certain no E30s were ever made that required leaded fuel. they don't have cast iron heads, so hardened valve seats are sort of a no-brainer.

Alloy heads can have soft seats too. I was explaining what his mechanic was talking about. I know for a fact E21's had a bunch of problems with valve wear when swapping to lead replacement fuels, so much more abrasive. Look it up, plenty of people suffering. Fuel companies came out with a bunch of warnings about changing straight to unleaded during this period. Here is an example from shell.

http://s04.static-shell.com/content/dam/shell/static/zaf/downloads/products-services/compatibility-chart.pdf

I said I would suggest the seats will be fine and you don't have to worry, but you need to run the right octane fuel. Telling the guy no E30 ever needed leaded fuel is just plain wrong. This car was sold and delivered here running on leaded fuel, the same as it was in the UK, sometimes you guys in the US fail to account that it is different across many overseas countries. If it wasn't, the OP wouldn't be in here asking is it a problem to run unleaded when it was previously a leaded car.

So, as I said, you just need to make sure you run a minimum 95 octane fuel because of the added compression ratio of the motor. It will ping and can suffer significant engine damage if you don't.

Edit: Just in case I still haven't made it clear enough. Im making the point that it was designed to run on a fuel here with a much higher octane rating (leaded), and it's this part of leaded fuel that is the bigger problem, not worrying about valve wear. I don't even remember seeing unleaded fuels here as a kid in the 80's. Just leaded, diesel and gas. I don't think it was until the late 80's, maybe early 90's that you started to see it at all service stations. Prior to that, everyone just ran leaded fuels, it used to just be called "super". Don't think it was even officially (ie before that you couldn't buy it anywhere in australia) made available until 1986, even new cars produced here prior to this ran on leaded.

[Herr Faust Schinken]

Germany started to limit lead content in gas in 1972 i think your fine

[nando]

still, I'm fairly certain no E30s were ever made that required leaded fuel. they don't have cast iron heads, so hardened valve seats are sort of a no-brainer.

[Madhatter]

Lots of misinformation in here. You guys in the US are forgetting you got lesser rated engines. They lowered the compression ratio for a lot of engines in your market. We don't have that in australia, we have the higher spec euro engines as standard.

thanks madhatter will go for 95 octane fuel even if it costs 25c more.
I have been running e10 for a year and for some reason found the idle to be smoother than 95. Was thinking of mixing 1/2tank e10 and 95 to save some money but havent tried it yet. I need to sort my idling issues anyway but thats another story.

My car is an 85 model e30 so does that mean the valve seats are hardened and dont need lubrication? I do have a bottle of valve saver and tend to pour a little too much every tankful so hope too much valve saver isnt going to cause a problem either. Will do it every 2nd tank from now.

BTW- Where is your garage in oz? Anywhere in Western Sydney? Need to find a good e30 mechanic local.

Some servo's (like united) have an E10 blended fuel that is 95. You won't have any problems with that, just the cheapest unleaded like you'll get at discount servos is often usually 93, which is too low an octane for the car. It varies a lot between companies, so you just have to pay attention to fuel types. In aus, unleaded fuel only has to be a minimum of 91, so depending on where they get it from, it can be far too low.

It can go either way. By the 80's they started making vehicles with hardened valve seats anticipating the banning and removal of leaded fuels. You really don't know until you look with vehicles produced in the early part of the 80's. Too much can foul spark plugs, leaves an oily residue on them. No real problems that are permanent, can run rough until it burns the deposits off the plugs.

QLD unfortunately. Maybe ask for suggestions on eurocca.net? members might be able to point you in the direction of a good garage in sydney.

I tend to suggest you'll be fine running unleaded just as long as you run the correct rating fuel.

I'm pretty sure no E30 ever needed leaded fuel. these aren't muscle cars from 1972.

E10 sucks for a number of reasons but it should be just fine.

We didn't get rid of leaded fuels until pretty late, started being replaced at average service stations in the later 90's and was banned in 2002. We didn't even have cat's on a lot of vehicles until the 90's, so we got a lot of the euro spec higher compression bmw engines here. For example, our 325i's are 9.7:1 comp ratio. The 323i's are 9.8:1, hence the higher rated fuels needed.

It won't, it's only 93 octane which is about your 88, though it could be as low as 91 which is 87. They were designed to run on premium fuel here, which is a minimum of 95, which is about your 91.

[dnguyen1963]

The main worry about using ethanol in older cars is that some or most of the rubber seals are not designed to handle alcohol. They can dry out and leak.

[Thujalvi]

For what it's worth, I never had any problems running my M40 316i on 95E10. I've been told that ethanol is the least of my worries with the stuff they put into the fuel these days, but I can't really say anything useful in that regard. Lead substitues aren't going to do anything useful, but occasional use of some sort of fuel preservant and/or cleaner could be worth it, maybe.

[nando]

leaded gas was banned here in WA in the '90s. unbelievable that it was still allowed anywhere in the last decade given the health effects of lead in the environment.

[jperris]

I believe all gas in 'Murica is E10 and has been for years - all our older cars have been fine, I guess. If I had a choice though, I'd take the gas without any ethanol in it - from what I understand, the non-ethanol-y stuff lasts longer and isn't quite as corrosive to the fuel system.

+1, most gasoline sold in the states has been e10 for several years, as MTBE, which replaced tetraethyl lead, has been banned in most states since the mid 2000's.

E10 shouldn't be left to sit for long periods of time as the ethanol is hygroscopic, meaning that it absorbs water from the surrounding air.

Also, ethanol is a strong solvent and may dislodge residual gunk in your fuel system and send it toward your engine. It would be advisable to service your fuel filter after your first few tankfuls of E10 and then continue to replace the fuel filter on schedule.

[jalopi]

I believe all gas in 'Murica is E10 and has been for years - all our older cars have been fine, I guess. If I had a choice though, I'd take the gas without any ethanol in it - from what I understand, the non-ethanol-y stuff lasts longer and isn't quite as corrosive to the fuel system.

[jperris]

Lead was eliminated as a fuel additive mainly because it fouled up catalytic converters. If your car came from the factory with a catalytic converter, it was designed to run on unleaded fuel.

E10 won't cause any damage to your fuel system.

As for octane rating, you should run whatever the owner's manual says if your vehicle is stock. Running a higher octane fuel than your ignition map is designed for is money wasted. My '89 325i owner's manual says to run regular unleaded, known in the states as 87 (AKI, or RON+MON/2), and known in oz, nz and europe as 91 or 92 (RON).

[nando]

I'm pretty sure no E30 ever needed leaded fuel. these aren't muscle cars from 1972.

E10 sucks for a number of reasons but it should be just fine.

[Jaxx_]

some reason found the idle to be smoother than 95.

you may not be imagining it, lower octane is easier to burn, so I imagine this is possible.

[lentildude]

thanks madhatter will go for 95 octane fuel even if it costs 25c more.
I have been running e10 for a year and for some reason found the idle to be smoother than 95. Was thinking of mixing 1/2tank e10 and 95 to save some money but havent tried it yet. I need to sort my idling issues anyway but thats another story.

My car is an 85 model e30 so does that mean the valve seats are hardened and dont need lubrication? I do have a bottle of valve saver and tend to pour a little too much every tankful so hope too much valve saver isnt going to cause a problem either. Will do it every 2nd tank from now.

BTW- Where is your garage in oz? Anywhere in Western Sydney? Need to find a good e30 mechanic local.