Cooling

[Sadden]

So i was having a conversation with dad about cooling the air charge on these cars and intercooling etc. He said another idea would be to run the gas lines through an icebox to make denser fuel.
Has anyone heard of this before?
Do you know what kind of gains this could produce?

[dirtracr95]

Yea its used alot in racing (not drag racing). every 11* you drop fuel temps raises its resistance to detention by the equivalent of 1 octane point or something simular to that.

[sandrock]

every 11* you drop fuel temps raises its resistance to detention by the equivalent of 1 octane point or something simular to that.

Funny. Any resistance I had to detention was met with swift and liberal force.

[bonnevillain]

LOL. I don't think it's worth it on anything but a track car though.

[Sadden]

Im assuming thats 11 degrees f?

[dirtracr95]

haha yea sorry forgot your north of the border. yea realistically its not worth it on a street car but if you got the spare time and money its not going to hurt or take too long to make.

[00Beast]

Something like that only works when you're able to stock it between rounds, at the drag strip, circle track, etc. It doesn't work on the street, unless you like pulling over every 20 miles to re-stock it with some ice and water.

[dirtracr95]

You dont have to do an Ice box though there are other ways to get the fuel cold. There is actually a very good summer setup using the accumulator from the A/C.

[00Beast]

There are much better ways to mitigate KR on a 3800.

[dirtracr95]

There are much better ways to mitigate KR on a 3800.

There is ABSOLUTELY no better way to get rid of KR. You missed the point. Its not that theres better ways were just talking about this way. You wanna point out all the problems Ill point out all the solutions.

[Sadden]

Is it worth looking into?
Yes i would like to do something like an icebox for the 1/4..
But you mentioned something with ac accumulator?

[sandrock]

That would mean having to run the AC full time. Who in the hell runs AC at the track, while ON THE TRACK?

[lewis26]

Is this before or after the dual supercharged engine and repaint?

[2000Silverbullet]

Cooling is definitely the key to killing knock.

Cooling the intake charge, either air or fuel, also has the added effect of increasing horsepower by 1% for every 10*F drop in charge temp.

This is very difficult to do without heat exchangers.

Intercooling works best, so does water/methanol injection although it is limited by reservoir size. My 1/2 gallon tank only lasts for 20 minutes of real world driving. Ice would last about as long. My trick is cooling the water/meth with ice.......works like a hot *dang*, even if it is only for 20 minutes.

The more heat exchangers you use, the better.

[01bonneSC]

Is this before or after the dual supercharged engine and repaint?

Youd probably gain more HP from deleting the AC copmpressor than u would using it to cool your fuel.

[BonneMe]

Is this before or after the dual supercharged engine and repaint?

Youd probably gain more HP from deleting the AC copmpressor than u would using it to cool your fuel.

AC compressor isn't loading the engine when it's not engaged. Like *dang* near every modern car in existance, It has a clutch on the compressor ...

[01bonneSC]

Is this before or after the dual supercharged engine and repaint?

Youd probably gain more HP from deleting the AC copmpressor than u would using it to cool your fuel.

AC compressor isn't loading the engine when it's not engaged. Like *dang* near every modern car in existance, It has a clutch on the compressor ...

still creating drag....

[00Beast]

A pulley in it's place creates about as much drag. The main gains are from the reduced weight of the system and all of it's components being removed, all 30+ pounds of it.

[01bonneSC]

A pulley in it's place creates about as much drag. The main gains are from the reduced weight of the system and all of it's components being removed, all 30+ pounds of it.

Yeah guess i didnt think about that youd have to replace it with another pulley....old school rodder in me, just pull it out and put on a smaller belt.

[dirtracr95]

That would mean having to run the AC full time. Who in the hell runs AC at the track, while ON THE TRACK?

Well if you run the A/C while your in line and let the accumulator get cold it will still cool your fuel even with the A/C off. If you like using your A/C during the summer when its hot then this would be a good way to cool your fuel when it needs it most. Or you could build a sealed Ice box around the accumulator so that It cools the fluid when the A/C is on then you could turn it Off and have a regular ice box that you can re-cool by turning on the A/C.

You could use a Fuel heat exchanger the same way you would use an external trans cooler. no HP loss there. Certain 80's BMW motorcycles use them because the tanks get too hot and the gas can boil in the lines.

If you have some fab skills you could use the shorter belt to bypass the A/C so it doesn't draw power from the crank, and come up with an electric drive. That's out of the skill level of 98% of the people on this site though.