93oct E30 Fuel

[NoHaveMSG]

Originally Posted by Spektyr

Nice explanation. I knew that higher E## gas got fewer MPG, but not the explanation behind it. According to the government study on E30 I read, a modern ECU can adjust the fuel mixture to run E30 even if the car is rated for E10 or E15. I'm not saying that's a good idea, or that it even applies to our specific cars - I'm just saying that's what a study (that may or may not have any bias) said.

So it sounds like if you had an E30 tune on a twin it would be a solid option. Probably not as much power as an E85 tune, but also probably better MPG.

On most cars you see the biggest gains between E40-50. After that the return diminishes significantly. It's very common to blend down to a lower percentage. It's also less demand on the fuel system.

Flex fuel tune is the way to go. Run whatever.

[Spektyr]

Originally Posted by NoHaveMSG

Flex fuel tune is the way to go. Run whatever.

True, but that requires extra hardware to detect the ethanol content, right? At least until the warranties start to expire I think at least some owners are going to want to be able to return to stock with a button push rather than a wrench if they need something done under warranty. (Assuming, of course, that the ECU doesn't tattle or can be made not to.)

[NoHaveMSG]

Originally Posted by Spektyr

True, but that requires extra hardware to detect the ethanol content, right? At least until the warranties start to expire I think at least some owners are going to want to be able to return to stock with a button push rather than a wrench if they need something done under warranty. (Assuming, of course, that the ECU doesn't tattle or can be made not to.)

Yeah. Depends on the type of kit though. Like the kit I have for my first gen ties into the EVAP and hijacks one of the EVAP compensation tables so I have to tie it into a wire on the ECU. Not easy to reverse.

A lot of kits just plug into the rear o2 sensor and hijack one of the o2 compensation tables. So you could just unplug it and plug the rear o2 sensor back in and flash back to stock if you wanted.