Fuel Cooler for 7th Injector - Anyone Tried It?

[Terbro]

Inspired by the guy doing a hot air '87, who's been experimenting with heating his fuel to vaporize it, I thought, why not use a fuel cooler to cool the plenum with a 7th injector. Moroso offers and insulated Cool Can fuel cooler: http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=2716&prmenbr=361

So one could run an insulated fuel line to the 7th injector. Using wet ice 0ºC would be good, using dry ice in the cooler (-70ºC) would be excellent. I don't know what the freezing tempurature of gasoline is, but if it's similar to alcohol, it's less than -70ºC.

Anyone try this?

Alcohol injection is achieving the same thing, right? Cooling the intake air at the plenum because of the cooling effect of alcohol. Maybe this is a cheaper alternative (using wet ice, that is).

Terry

 

[turbosam6]

One of the twin turbo cars I saw had the fuel cooler on it, but I think it was for all the fuel, not just a 7th injector. I've thought about doing something like that before. But I think maybe a 25 shot of nitrous would work better. I've considered putting the shot before the intercooler, to drop ic temps. Anyone do that?

 

[turbo buicks]

terbo, are you talking about bruce's experiment on www.gnttype.org ? i would also like to see his results. he mentioned in a previous thread he does 28 psi on pump gas. id like to see what his max boost level is now. are you out there bruce???

 

[Terbro]

Turbosam - Someone suggested a small shot of nitrous right into the IC once. I'm thinking along the lines of cheap, and running it full time...

...yes turbo buicks, I'm referred to Bruce's experiment.

Terry

 

[bruce]

Originally posted by turbo buicks
terbo, are you talking about bruce's experiment on www.gnttype.org ? i would also like to see his results. he mentioned in a previous thread he does 28 psi on pump gas. id like to see what his max boost level is now. are you out there bruce???

I've actually dropped back to 26.
And with the cold roads, it's hard to get much traction.

You won't be seeing me post numbers for gains. I'm tired of the games people play with posted numbers. I might post some MAT numbers when the warms, and I can get some similiar numbers to similiat weather conditions.

With the replumbing and a few other projects going on, I'll be dropping back to 15ish for a while.

There are some differences in what works in a carb'd engine and what will work in a S/C T/C application. Cool fuel can make a big difference in a carb'd application since the fuel has a long route to the intake valve, and it can readily fall out of suspension. The fuel load in a N/A displaces about 10% of the charge volume so the net result of cold fuel does work well there.

Cooling the plenum is just one element of what I'm doing. You got to look at the big picture. If you want to try the chilled 7th injector then go right ahead. But, I think you find poor distribution. And remember I mentioned my manifold isn't stock, and that the plenum floor is lower then the runner's floors.

 

[turbo buicks]

cool bruce, sounds quite interesting what you come up with. i for one dont have the guts to do this and your car has other things only you know you have done to do this so ill just stick a big FMIC on it for now i am truly boost envious of you, 28 psi on pump gas, sheesh

 

[blackbuick87]

Dont see much gain by only cooling 1/7th of the fuel going into the engine. Cooling all the fuel would give more substantial gains, and it would be all the time, not just when the 7th kicks in

 

[turbo buicks]

i think bruce is using the fuel to cool the manifold surface and reduce MAT temps in his 87 hot-air conversion. his plenum isnt stock either, the floor sits below the runners, like a bowl i would guess.

 

[Ormand]

Why?

Cool fuel on a carburetor keeps the fuel liquid so the carb can meter it. This isn't needed for an injected engine. Cool fuel in a carb will also "richen" the mixture, since the cooled fuel is denser than what the carb expects. But the seventh injector takes care of adding more fuel, cooling it won't change that- and in closed loop, it won't even affect the mixture at all. The actual temperature of the fuel doesn't contribute an a whole lot to the "cooling effect", anyway. The heat that's absorbed when the fuel vaporizes is responsible for most of the cooling. It might even be better to have the fuel hot, so that it would vaporize more easily. If you want more cooling, go with alcohol to the 7th injector, it cools more than gasoline.

 

[Terbro]

It's understood that alcohol cools more than gasoline. That's why I'm proposing to cool it. It might show to be equally effective as alcohol...cheaper to set up, and cheaper and easier to use.

But I don't know...that's why I'm asking.

Terry