<VV> Re: Corvair running on E-85

[Jim Burkhard]

Hey Paul-

Interesting stuff!  Can you let us know how long (miles and 
days) it takes before you have to change the carbs, fuel 
lines, tank, and sender because of corrosion? Oh yeah, if 
you are running a mechanical pump, the elastomers in the 
diaphragm will not survive, so carry a spare, a big fire 
extinguisher, and watch the "oil" level in the  crankcase. 
If it's an electric pump, corrosion will probably be the 
death of it.

I'm an engineer who works for the world's largest supplier 
of automotive fuel systems.  Even E20 (20% Ethanol) requires 
special attention to materials throughout. With 85% ethanol, 
you really need to seriously bring out the ethanol-proof 
parts -- lots of 300 series stainless everywhere and special 
material gaskets, hoses, etc. It's not a minor problem at 
all.  I can't think of *any* OEM Corvair parts in contact 
with fuel that will be happy with E85 for long. They just 
didn't design the parts with that in mind.

If you are going to quote fuel mileage to people on the 
list, it would be most helpful if you could do the math and 
compare with gasoline on a "miles per dollar" basis (or 
furnish your E85 mpg values with the current price/gallon). 
The low heating value and much lower stoichiometric ratio 
(i.e. you have to run much bigger jets) screw up making any 
direct comparison in terms of miles by gallon.  I can tell 
you that at $2.11 per gallon, although undoubtedly 
subsidized heavily, the economics are wholly uncompetitive 
with gasoline.  You are going to find your miles/$ fuel cost 
going up significantly. Those 0.063" jets are going to flow 
plenty of the stuff!  :-)

For people thinking of running it as a race fuel (as Paul 
suggests):  Yes, it can do this well (better than as a road 
fuel in fact), but unless you have really built the fuel 
system (from tank to carbs) to handle the high ethanol 
content, you are going to soon have trouble. If you don't 
want to run ethanol-proof materials, plan on flushing the 
fuel system with gasoline after every race.  I have friends 
who run modified midgets (motorcycle engines in a dirt track 
car) and that is their regular routine.

Keep us posted on your results, Paul.  I'm curious how many 
miles and/or days (it will probably be mostly time based) 
before you have problems.

best of luck,

Jim Burkhard

-------------

Paul Fox wrote:
> Group,
>            A gas station just started selling E-85 here in Indy. I thought I'd give it a try in my beater 110 hp Corsa. I knew that I'd have to change the carbs jetting. But I put some in with the stock jets (.050 or #50 in 63 carbs with no power valves) just to see how it would work. It displayed signs of being to lean. But it ran a little better as it warmed up (the engine and the weather).
>           I called my engineer dad who did a little reserch and figureing and came up with .063 for a jet size for me.I just drilled the jets with a 1/16 drill bit. I knew I would need more accel.pump too so I drilled the holes to .025.
>            The octane ratring on the pump was 105 so I cranked the timing up to 25 degrees from about 12. There is no ping or knock at all.
>          So far it runs great. I'll keep everyone up dated on mileage ect. as I use it. I was getting about 18mpg around town with the 3.55 rear 4sd. transaxle. This is with a very tired engine.
>          I think this stuff might be fairly good race gas at $2.11 a gallon.
>                 Paul Fox