[Balr14]

Has anyone tried E85 in a Z4? It was not uncommon in a couple other car brands I owned. But, I haven't seen any mention of it here. Just curious. Plus, we don't have much to talk about around here... it's a small group.

[GerryC]

No, and I haven't heard of anyone trying it.

Switching to E85 is a good idea if you're adding a lot of boost. So with bigger turbos, injectors, and a complete re-map, you could probably get 600-700 hp. The question is who needs a 600 hp RWD Z4?

It might be worth it if you had an M4 CSL you wanted to take to the drags.

OTOH, there might be a few Supra owners who've done it.

[gkgeiger]

For the average person, E85 is a waste. When we got our first E85 available car we saved a few cents per gallon but got 25% less mileage. Ymmv

[Balr14]

Today, around here, premium is $4.70, E85 is $2.65. That seemed to be reason to consider it. But, I wouldn't try it if I had to do any mods or impact my warranty. I didn't buy a Z4 expecting an economy car and don't drive enough miles in a year for it to really matter. I just don't like wasting money.

[Westside Guy]

I have no interest in using ethanol fuel in my Z4.

[GerryC]

Originally Posted by Balr14

Today, around here, premium is $4.70, E85 is $2.65. That seemed to be reason to consider it. But, I wouldn't try it if I had to do any mods or impact my warranty. I didn't buy a Z4 expecting an economy car and don't drive enough miles in a year for it to really matter. I just don't like wasting money.

Switching to E85 is wasting money. The cheaper price per gallon is enticing but E85 has way less energy than gas. You can’t run it without mods to the fuel mapping or you’ll destroy the engine as it will be running extremely lean. BMW states a max of E10.

There are “FlexFuel” cars that have a fuel sensor that detects E85 and allows the DME to adjust its fuel mapping. I had one 15-20 years ago. Ran a test on E85. Cost per mile went up about 10%.

Drag racers like E85 as it helps cool the charge when running large amounts of boost. Cooler means more power.

[Balr14]

Originally Posted by GerryC

Switching to E85 is wasting money. The cheaper price per gallon is enticing but E85 has way less energy than gas. You can’t run it without mods to the fuel mapping or you’ll destroy the engine as it will be running extremely lean. BMW states a max of E10.

There are “FlexFuel” cars that have a fuel sensor that detects E85 and allows the DME to adjust its fuel mapping. I had one 15-20 years ago. Ran a test on E85. Cost per mile went up about 10%.

Drag racers like E85 as it helps cool the charge when running large amounts of boost. Cooler means more power.

Thanks. That's the kind of insight I was looking for.

[blue135]

Have run E85 in my 2010 Colorado V8. It is designed to rum that much ethanol. During the week after Hurricane Ian last year, it was the only pump with fuel. Ran fine, but the cost savings were not there (clear difference between price and cost).

[BEAR-AvHistory]

Requires a tune to make any sense.

[stlcdr]

If you want more power, the vehicle needs tuning for ethanol.

If you want it to make sense for the 99.9% then the price needs to be less than the loss in economy. Which can happen. I ran a suburban on E85 for several months, when the dot.gov was trying to promote it as a ‘green’ alternative with significantly lower prices. That is, it was just under 2/3 the price of regular gas (I got 2/3 of the fuel economy than regular).

The price differential didn’t last long. It’s simply not economically viable. In addition, the more frequent fillups had a psychological toll (a significant reason for ‘range anxiety’ with electric vehicles).

[Sheharyar_rr]

I have port injection and lpfp upgraded with pure850 turbo. Makes about 700whp on e70 mix.


It’s a ton of fun

[Balr14]

I'm sure that car is way more fun than I can handle. I have no self-control!

BTW: E85 is normally $2.00 less than premium around here... 2.69 versus 4.73.