jetting a carb for ethanol gas E-10 & E-15

[Dingie 2]

A buudy of mine and I where talking about jetting his V-4 . He said that he was going to jet his motor to a common jet size that was used prior to E-10 and E-15 use. I told him that he may want to run a larger jet than we used with non-ethanol gas. I know that back in the day when Ethanol hit the gas pumps in our area of Fl that I enlarged my fuel jet size by 3 % because E-10 was 13.7 to 1 and the old safe gas was 14.9-1.
Todays gas has oxygen added ethanol. I know that the gas at the pump is not always the same but does anyone have a formula that shows the correct jet size increase that someone should run when they switch from non-ethanol gas to 10% or 15% ethanol gas ? Thanks for any help
Joe Raimondo

[terry taylor]

If it,s stock, use premium 91 with stock jetting and full synthetic oil thanks.

[dcarter]

it is not stock. I am using 93 premium for among other things higher compression heads per builder.

[terry taylor]

it is not stock. I am using pemium for among other things higher compression heads per builder.--------------------------------Perhaps the builder could have the suggested specs. for carbs. thanks.:)