Possibly dumb question..

[Chogokin]

a couple gallons e85 per tank is fine. Just be aware that it will steadily grow to a higher percentage as time goes on unless you're running your tank dry(which you aren't). Highly recommend the Innovate ethanol sensor/gauge kit on ebay. It's like $185.

That's why I don't do consecutive tanks of mixing E85. I'll be several tanks before I mix again.

 

[MonkeyMD]

That's why I don't do consecutive tanks of mixing E85. I'll be several tanks before I mix again.

I have a spreadsheet that calculates percent ethanol taking into account previous tank. Is it as good as an ethanol gauge, hell no because you never know what you're getting from the pump. What it does do is prevent me from going over about e30 which I think is the limit of stock fueling system at least for conservative tunes, because pumps are max e85