C.M.Jones

Im building a SB 350 and I am thinking of going E85 so I can run high compression. I know there are "E85 carburetors" but is that really necessary or a marketing ploy like "HDTV antennas", lol or can I get the same performance from E85 using a properly jetted standard carb?

IROCZ28KevinZ

iTrader: (2)

An E85 carb may have a special coating or be made of special materials that can withstand E85. E85 requires special gaskets, seals, and rubber otherwise it will destroy normal fuel system parts.

InfernalVortex

iTrader: (4)

Im not so sure that's true. Methanol is VERY corrosive, but E85 isnt that bad.

I remember reading an old E85 thread where someone did an experiment and dropped a carb into a bucket of e85 for a few months and said it was fine afterwards.

But still, you can get new gaskets/seals/rubber for e85 probably with no problem if they're available/needed.

fleetmgr

An E85 carb will have special seals, and be jetted differently than a standard carb.

five7kid

iTrader: (14)

Not true. Modern fuel systems are compatible with ethanol.

I've been running E85 in the '57 with a stock tank and pick-up, and off-the-shelf aftermarket pump, lines, regulator, and carb materials, since 2006.

Tail light lenses are a different story. They are not compatible with ethanol. . .

Jetting and metering is different for E85. The special E85 carbs are worth the price in that regard. I started with a Proform mainbody-converted Holley double pumper, and by the time I was finished, I would have spent less money buying an E85 carb from Quick Fuel Technology, and had a better carb in the end.

By the way, there is a link to an E85 thread in the "welcome to the carb forum" sticky.

There is one problem running E85 on the street in a carbureted vehicle. Well, actually 2. The first is the E85 carbs aren't emissions legal. The second is during the winter, the E85 changes to "E70", and they don't have to tell you what percentage they're selling you. Flex fuel vehicles don't have a problem with that as they sense the percentage of ethanol and gasoline and adjust the system to compensate. With a carb, you'll have to take a sample of every tank and rejet to match the mix you've got in the tank. And, the carb metering other than the jetting will be affected by the change in the ratio.

C.M.Jones

not worried about emissions as we don't have them here

I am worried about constantly having to check the percentage and jet accordingly as this will be a daily driver. The minimum is E70 and the max of course is E85, now if I set it for E85 does this mean it simply won't run as well with E70 or it won't run at aLL?

I heard they lower the percentage in the winter to help with cold starting, that's ok with me, as I don't plan on racing my car in winter in colorado.

maybe I should meter it for E75 and call it good?

five7kid

iTrader: (14)

It'll be rich with E70.

If you set it for E75, it'll be lean with E85 and rich with E70.

C.M.Jones

is your 57 a daily driver or is it strictly a strip machine?
would you recomend a E85 carb on a daily driver?
how rich are we talking? here in Colorado, I was "told" that its 85% for most of the year and in the cold months its 75%. If I set it up for 85% then is it being rich for a few months a huge deal?

five7kid

iTrader: (14)

The '57 is driven to and from the track.

I've been buying E85 at the track for the last 2+ years because of performance variations using gas station product. I didn't try to test what came from the gas station, but can rely on the track tank to be filled with 85% mix.

For daily driving, a flex fuel vehicle certainly keeps it simple. If you do go with a carb, you'll probably be fine with two sets of jets, one for spring/summer, one for fall/winter.