Alcohol fuel temp

What effect would lowering the fuel temp for alcohol have on performance? of course all else being equal

 

Lowering the temp. increases the density which increases the amount of fuel charge which increases the power output. However, I'm sure their is a lower temp. limit.

 

You sure about that ?

 

call Dennis Taylor..Dave

 

Ora says alcohol makes it's most power at 60 degrees.

 

if Ora said that then my temp will be 60deg. Dave

 

Question for those that aren't doing anything special to control fuel temps.
What temperature do you record and where do you measure it?

Just curious what the average race day fuel temp might be (without controlling it).

 

I have been told from several outlaw racers they put it in the deep freez then take it out and use it..they said ..cold..Dave

 

Have done this and the only difference I see is when the air temp is over 80 degrees. If your fuel is 70 or below...give or take....that's as good as it gets. We've put it in at -20 and saw absolutely no difference, we were looking for a lower manifold temp. When the outside air is 108 and your fuel is 50ish, it will lower the manifold temp some.

Brandon Booher
NHRA TAD #35

 

Lots of speculation out there about this, I can tell you first hand what happens.

All it has done for any car I've seen do it, whether at -20 or 50 degrees is keep your bottom end happier if you're running on the edge of detonation. Won't even keep you from tagging pistons now and again.

 

temp affect is complex

A lot of pit buz that cooler fuel runs better. The previous responses provided some good examples.

METHANOL VAPOR ISSUE: We found in our methanol publication development that only methanol vapor burns. So much of the methanol in the cylinder is liquid, and large & small droplets. And not vapor. Anything that is not vapor does not burn. There is not enough time to vaporize. Furthermore, with liquid methanol in the cylinder, you get ignition vaporization at the expense of ignition.

MAYBE GOOD, MAYBE NOT: In some racer combinations, cooler fuel will be better. That would be the case for a hot day with an engine tuned to the edge of detonation. Yet in another engine, say on a cool day, that is somewhat rich and tuned with more spark advance than the norm, also tuned to a leaner idle than norm for more staging temperature, cooler fuel may not help at all. It will only reduce vaporization and make less power.

TEMP: Below 50 degrees in one atmosphere, there is little to no vaporization. Above 149 deg. in one atmosphere, there is all vapor. At boost and compression, different tune-ups make different temperatures and different amounts of vapor. There are so many different effects on vaporization and the horsepower result that a blanket rule will probably not work across the board.

REFERENCE: We discuss this in great lengths in our methanol publication with a lot of engineering and racer data. Over 30 pages provide Information about temperature. Over 60 pages provide Information about vaporization.

An extensive index of TERMS (6 pages single spaced) can be downloaded from our website; from the book description page. To give an idea of how vast the subject matter is.

Bob Szabo, author: 5000 Horsepower on Methanol
www.racecarbook.com