[Sam Tango]

Tuning noob here. How easy or difficult is to deal with ethanol? I want to tune my car, but am worried about messing it up when I use ethanol maps.

Is a flex fuel kit mandatory? Can you reliably mix ethanol at the pump without a sensor?

[Jnasratyar]

Originally Posted by Sam Tango

Tuning noob here. How easy or difficult is to deal with ethanol? I want to tune my car, but am worried about messing it up when I use ethanol maps.

Is a flex fuel kit mandatory? Can you reliably mix ethanol at the pump without a sensor?

I mean you can mix without a sensor, but you’ll never really be 100% sure on the mix so it’s kind of bad. I’d just get a flex fuel sensor, soooooo much easier that way.

[ichigom340i]

I bought some testers to test the gas for the amount of ethanol in the gas. my 85 ethanol around here is right at 85 percent and my 93 octane is between 8 to 10 percent. It’s usually around 8 in the colder months I’ve noticed. They have apps for android and iOS to help calculate the percentage. You just have to know the amount of fuel in the car to get the calculations right. Kern417 has a older video about how to do it. https://youtu.be/_vbqcIDlOC4?si=2iuVMv3_-_LfvDPo If you have the bmw app and pay the yearly fee it will show you the percentage in the tank which made it a lot easier. It’s definitely a pain but after doing it a few times it’s not so bad. I am ordering a analyzer soon for the convenience and able to see an actual number. But from a few samples I’ve taken after a fill and some driving it’s marks at 40 maybe 41 percent after a mix. My target is 40 I am using a MHD stage one OTS e40 tune. No issues at all so far.

[abbike18]

Just get a dynamic ECA and flex fuel tune. Then you never have to worry. You can fill up at any E85 station and do rough calcs and it doesn't matter. I find ethanol stations vary widely so it can be hard to hit the mark perfectly every time. Why spend so much time not being sure on your e content when there is a solution to not having to be precise?

[Sam Tango]

Originally Posted by abbike18

Just get a dynamic ECA and flex fuel tune. Then you never have to worry. You can fill up at any E85 station and do rough calcs and it doesn't matter. I find ethanol stations vary widely so it can be hard to hit the mark perfectly every time. Why spend so much time not being sure on your e content when there is a solution to not having to be precise?

how well do these things work in the long run? after all, its an aftermarket part

[mike@x-ph.com]

The flex fuel is not mandatory but makes it so much easier

If you are using a jb4, get the fuel-it kit; if you are using bootmod3, get the PTF kit.

[pdxtiger]

Originally Posted by Sam Tango

how well do these things work in the long run? after all, its an aftermarket part

Most kits actually use an OEM GM sensor, so longevity isn't an issue. I highly recommend disassembling and reassembling the fittings before installing though, just to make sure the o-rings are in good shape etc and it wont suddenly start leaking because one is bound up (ask me how I know lol).

You'll wanna read up how to run ethanol from a practical perspective too. You don't want to run it every single tank, you don't want it to sit with a tank of it for extended time periods, and you don't want to short-trip the car on it constantly, it really needs to get up to temp or you'll get a ton of water in your oil. You'll want to do more frequent oil changes as well.

It's absolutely worth it though, great power gains and it smells lovely.