93turbo16

Really as long as you know exactly what you are putting in the tank you are fine.

You could buy an alcohol test kit to test the fuel you are putting in before hand so you know exactly how much alcohol is contained in the fuel. This would be helpful if you are using as strictly a race gas option for the times that the car goes to the track.

Gernby

In the 20+ years I've been driving, I've NEVER really known what I was putting in my gas tank.

93turbo16

And you shouldn't have to as long as you are running a normal gasoline blend from the pump, since they won't change THAT much from winter to summer.

But when it comes to E85 it does make a difference if you are planning on using the fuel as a race fuel only. It is nice to know exactly what you are getting from time to time.

Hondata

You can either calculate the ethanol content with a kit (fairly easy - involves adding water in a graduated tube to determine solubility) or use a ethanol content display gauge. Usually they change the E85 ethanol content 4 times per year - summer, shoulder, winter, shoulder, summer etc.

wadzii

on an ap1, the stock injectors are too small for E85. I have only an intake and AEM EMS, i was hitting 100% duty at around 8300 rpms with a lambda of 0.83ish. at 9200 it was at 0.87-0.88