I'm looking to do an E85 conversion, current setup is a Carbed 383 w/Holley 750 vac. Still have the stock L98 in tank pump and will most likely go to an external in line. Any thoughts on fuel line size, -6an or -8an? Motor is a stout 383 GMPP short block, Milled 55cc AFR eliminators, 10.82:1, comp cams .510/.520 230/236. Best idea for carb pickup? Has anyone done an E85 conversion!? -Alex

I've been running E85 in the '57 since 2006. I'm using 3/8" line. I would recommend keeping an electric pump back in or by the tank. I used a mechanical pump for the first couple of years, but went to electric in '08 and removed the mechanical.

If your in-tank is a stock factory TPI unit, you'd be best putting in a better pump. The Walbro 255 would probably be enough.

I would like to add some info, as well as pose a question about E-85 carbs.

Some, if not all gas companies mix their E-85 at the pump, and because of this, the ratio of ethanol to gas is not always consistent. this does not really matter to a FI flex fuel vehicle, but the same carb will not be able to adjust itself for the different ratios, so has anybody had to deal with this?

I've never heard that E85 is mixed at the pump.

I do know the ethanol percentage can be anywhere between 70% to 85%. They are not obligated to post or disclose what their percentage is. The pumps do say "for flex fuel vehicles only", and flex fuel vehicles automatically compensate for whatever percentage ethanol there is in the tank.

I started buying my E85 at the track for this reason. I know it will be 85% each time. An alternative would be to get a kit that allows you to test for the ethanol percentage and jet for whatever is in your tank.

I did not know they sold E85 at the track, is it more expensive.

They sell it at Bandimere Speedway.

It's a lot more than the least expensive stations, a little more than the most expensive stations. But, I've never had quality issues with it when purchased at the track.

All the E-85 around here comes out of a tank just like the gasoline does, no mixing involved!!!!

We live about 10 miles from an ethanol plant, a little talk with the right person gets a 55 gal drum of E-100.... The correct blending with E-85 will yield an E-90 mix, this is what we use in the drag cars... Consistently 112 octane!!!!

When we went to the Div 5 finals in Topeka last year, I hadn't filled up my fuel jugs with E85 before we left. I wasn't too worried about it, because there was a station about 10 miles from the track that carried E85. When we went to fill up, we discovered the station was closed. We couldn't find any anywhere in Topeka. My sister lives in Lawrence and knew of a station there, so we drove over there. Their pump had several choices, from E10, E20, E70, and E85 - but each pump only had one hose. The last customer hadn't taken their receipt, and it showed they purchased E20. I was a little concerned that the stuff in the hose was mostly gasoline and "diluting" my E85, so when I used that jug, I only took about a gallon at a time and mixed it with a gallon from the 2nd jug I filled. I don't know if it made any difference doing it that way; when I got back to track E85, I didn't notice any difference.

I'm thinking of running one of the jeg's methanol pump kits, I'm not sure how cost effective the Walbro is, or if it's compatible with e85? (is it?) Also I believe a guy sent you a thread quite a while back about fabbing up his own carb pickup, it looked like 3/8" pipe and he soldered a strainer from a 2nd gen fbody onto it? If I keep an in tank pump, do you think the stock fuel lines would be large enough for the alcohol? I believe it's a 3/8 feed and 5/16 return. Thanks again for the mile high help neighbor!

It's a sticky in the top section of this forum.
Should be good well over 400 HP. I've fed the 396 plus a 100 shot with a 3/8" line.

I'm having a problem with it cutting out on hard pulls from 4000-6000 rpm, I checked the fuel pressure and it's at 6.5psi. The pump is only about a year old (bosch), also it's an intermittent problem. Do you think the stock 5/16 return line is too small? I had another 91 RS vert with a similar zz383 and same 750 combo and in tank tbi pump w/regulator and never had this issue.

Is the fuel pressure still at 6.5 psi when it's cutting out?

I spent hours researching e-85 and I have found numerous people running it in regular cars with no problems as well as a company that ran it in a non flex fuel 2000 suburban for 108k and the whole engine and fuel system including pump were in better condition than the same truck with regular gas.
I am def running e-85 in my 383 when I get it all squared away does anyone know how to set up a 750 vs holley for e-85?

That I'm not sure of, I have the pressure gauge under the hood and it only seems to do this when under load driving the car. It doesn't cut out if I rev the motor out of gear, and again it's intermittent. By the way, thank you very much for your help! You have a great rep on thirdgen for a reason.

Try and google this- AED 4500A HOLLEY E85 750-1250 DOMINATOR CARBURETOR KIT

Also found them on ebay, and atlanticspeed.com

Hey I was wondering, you suggest the 255lph pump, from my knowledge that is at high psi (60-70ish) where it flows that much. Do you think it'll still flow enough at 6psi? I had a 91 RS Vert ZZ383 with a stock tbi pump and it never ran dry, but it's hard to fathom putting a stock pump in where a stock pump already is..

Also, I was looking in my old Gm power book at the 3rd gen ZZ3 H.O. Camaro, it had a high flow in tank pump ACDELCO Part # EP386. It was good for it's 308 hp, but I can't find any flow numbers if it'll run my hungry 383. Any thoughts? And thanks again for your insight!

Flow increases as pressure decreases. But, 255 lph is a free-flow rating. It should be fine at 6 psi.

That makes perfect sense, that looks like the right pump. Thanks again!

In hindsight, I should have just bought a carb already set up for E85. I learned a lot going through the process, but I spent almost as much as a ready-to-run E85 carb would have cost. Quick Fuel Technology and others have them ready to go.