# Thread: Forced induction theory questions

1. ## Forced induction theory questions

I was looking at the new Superduty Ford 2008 on the internet the other day and noticed that they made a big deal of the fact that they are cooling the fuel from 140-170 degrees down to 70+- degrees. This is the new twin turbo 6.4L diesel.

These are direct injection motors, so how would a spritz of cooler fuel help build more power? The air in the cylinder after the valves close has a certain volume of oxygen, and a cooler spritz of fuel helps how again?

Someone school me with a little theory.........

Smack your computer screen to help me get the moths out of my brain.........

2. Just another way to take heat out of the combustion chamber which will help fight off detonation (and if you can lower your intake temps you can thereby run a little more compression, boost, etc...and make more power)...

It's really very similar theory to cooling the intake charge with a intercooler just applied to fuel instead of the air...

3. Cooler intake charge = more density = more power.

4. Originally Posted by qbzonk
Cooler intake charge = more density = more power.

Exactly!!!!

5. Beating a dead horse (so removed)...

6. Like the other 2 said above. The more heat you can take out of the combustion chamber the more power you are going to make which in turn lets you turn the boost up if so desired. In the diesels a lot of people run propane injection which further colls the air charge after the intercooler.

Myself personally use methanol injection on my car and it lets me turn the boost past 30psi still running 93 octane. If the methanol wasn't present in the air charge at that boost level the motor would last about .0000001 seconds and either melt a piston or break a rod due to the extreme detenation. Using this method has trapped into the low 130s in the 1/4 mile.

Diesels are a tricky animal but there is a ton of hp/tq that can be had by a few minor bolt-ons.

7. This thread has got me thinking.

If anyone watches NHRA drag racing, the top-fuel dragsters which run on nitro-methane use more fuel to cool the combustion chambers than fuel is burnt. Remember all the "fire" you see coming out of the exhaust?

8. Its a whole different engineering platform. Top fuel. The cylinders are actually at a point of hydro lock.

9. Ok Thanks guys........

I just didn't think that coolng the fuel itself would matter much.......