Thinking about running E85

[jlwhorf]

I have been thinking about running E85 for some time, and now I have a supplier not far from me. I currently use an 80/20 mix with 93 and 110 gas, estimating it to be about 96 octane. I have a late model stock car that I converted to a road course car. I run a 359 ci chevy, 10:1 cr, mechanical roller 252/258 .630/.630, 200 cc intake runner alum heads, forged pistons, 4340 crank and rods, and dry sump. My fuel system includes a Holley 830 HP with annular boosters, Holley 110 gph pump, and a Jaz fuel cell. I run 1" aluminum fuel line and connect it to the pump with rubber hose. I connect the pump to the carb with 3/8 rubber hone to a -6 dual line hose kit, but do not run a pressure regulator.

I feel the carb should be no problem to convert, but what about the rest of the fuel system?

Do I need a regulator because the pump is rated at up to 8 psi.

What is the best way to set the fuel mixture for a do it your selfer (reading plugs?) or should it be set up on a dyno with the air/fuel mixture read.

Can a conventional double pumper be converted to run e85 by enlarging or converting air bleeds to screw in? I have a stack of holley double pumpers and would concider converting one of them if it is a safe conversion.

Does E85 have oil dilution issues like methanol?

Thanks

[Heath Daniel]

jlwhorf welcome to the board. You threw out a lot of questions that all have answers to. I'll go through some and I'm sure others will be glad to jump in and share there experiences as well. I just checked out the features on the 830 HP annular booster carb on Holley's site and it looks like a great carb to convert especially if your happy with it now. I'll start with your plumbing. I'm a little confused about going from a 1" feed line into the pump and out with a 3/8. If I'm not mistaken a -6 is about the same as 3/8 so you may want to step up a bit coming out of the pump with something like a -8 or 1/2' to a Y block then out with two 3/8 or -6 to each float bowl on the carb. If the pump does flow 110 gph and maintains 8 or below pressure than you should be okay if that's how it's running now. Personally I would go ahead and plumb in a regulator just so you know where the pressure is and if you decide to upgrade the pump it's already there. As far as the material, rubber hose, aluminum line goes, no problem. You can read plugs and watch your water temp. Nothing special is required to tune E85. Just a good working knowledge knowing when your motor is happy and when it's not and how to make it happy. Conventional double pumpers make great conversion cores. Several things have to be done to them in order for them to be right on E85. E85 does not, let me say that again, E85 DOES NOT have oil dilution issues like methanol. I can tell you jlwhorf that you motor combination will love E85.

[jlwhorf]

Thanks for the great info. Just another quick question reguarding storage. I usually race once every month or 2 in the summer, should I drain the carb after each event or can I let it sit it with e85 in the float bowls for these periods of time.

Thanks again

[Heath Daniel]

We leave E85 in our race car all season but we like to keep it moving. If we have a stretch between races of a month or so (which is not very often) we will back it out of the garage and fire it up and let it run and warm up just to keep everything moving. We do drain it out over the winter where it sits for about 3 months. Usually because we are doing something else to it like chassis or transmission work where we can't back it out.