forced induction for road racing

[StickShift84]

As the title suggest I want to know everyones opinion on which type of forced induction would be best for sreet and road racing?

Roots/ Twin Screw positive displacement - Awesome low end power but heat soak issues.

Centrifugal - cheaper, builds power the slowest, easier to maintain temperature

turbo - most power, quick hit of power

 

[gashog]

If its auto x, I'd say stay away from forced induction. But if you're tracking the car It depends, short track with lots of curves go with a smaller quick spooling turbo or screw type charger. Or a long track, with lots of top end blasts, go with a big turbo. Different FI for different things.

 

[Towelly]

You can use any type of power adder but nitrous if you ask me. It just depends on your setup.

You could do a centrifugal supercharger in a blow through setup with a extremely small pulley. That'd spool fast kind of like a PD blower and still have the top end.

You could do a turbo. Just make sure you match a the turbo to your car. Just don't go out and buy the biggest turbo in the world and expect it to spool fast. But also you don't want to go to small so you run out of effeicency.

Also you could do a posative displacment blower. But make sure you get a big aftermarket heat exchanger and plenty of injector to keep the combustion chamber as cool as possible for as long as possible. Also you would want the biggest coolant tank you can fit under the hood (or elsewhere) . Just don't expect traction comming out of the whole in the real tight stuff unless you have a really trick suspension setup and some fat rubber.

It all depends on how much you want to spend and what you want to do. The biggest factor as always is the $$.. The more $$ the faster your going to go.

In my opinion the best of both worlds is a Centri blower with a blow thru setup and a big ass air-air intercooler/aftercooler.

 

[Hoboattacker]

Well, the arguments about low end power w/ a centri are null here. You are road racing and in road racing if you dip below 3k rpms you aren't driving right. Above 3k rpms, the Centri's make pretty good power and will feel "insta on" feel since you will be right in the power band. Easier to keep cool and it's cheap, good idea for road racing. The only thing is that it is forward of the motor just like the turbo's are (unless you go with an STS system)

Positive displacement blowers would be nice but they raise your center of gravity. They aren't hard to keep cool, either. Just buy this: http://www.killerchiller.com/index.html

The Killer Chiller was designed by my tuner and one of his friends and it's fantastic. He has a customer that has a Lightning with the KC on it and he is rocking 60-70˚ IAT2 temps all day long and he lives in Mobile, AL.

 

[Towelly]

Well, the arguments about low end power w/ a centri are null here. You are road racing and in road racing if you dip below 3k rpms you aren't driving right. Above 3k rpms, the Centri's make pretty good power and will feel "insta on" feel since you will be right in the power band. Easier to keep cool and it's cheap, good idea for road racing. The only thing is that it is forward of the motor just like the turbo's are (unless you go with an STS system)

Positive displacement blowers would be nice but they raise your center of gravity. They aren't hard to keep cool, either. Just buy this: http://www.killerchiller.com/index.html

The Killer Chiller was designed by my tuner and one of his friends and it's fantastic. He has a customer that has a Lightning with the KC on it and he is rocking 60-70˚ IAT2 temps all day long and he lives in Mobile, AL.

Wow. Thats freaking sweet. I didn't think about how a PD blower would raise your center of gravity. Thats a real good point if your looking for better handling.

Although I don't think you would have a problem keeping IAT's cold enough as long as you have a good/big enough Heat Exchanger on a PD blower. The new AFCO exchanger would be a lot less crap to worry about and you would still keep the IAT's down enough. Even on a road coarse or in Auto-X.

 

[Hoboattacker]

From what I understand, there is basically no way to keep them as cool as with the KC and it's really not all that much more to worry about. It take the IC fluid and drops it to around 35˚F which in turn keeps the IAT's way way down. The AFCO HE is still a great idea though, don't get me wrong. I just think that the KC would give you the lowest IAT temps possible with FI.

 

[Snooze]

Road racing.. Is driver skills.(imho)
If both cars have 500hp, slicks and fairly stable and rigid cars, then how they make the power means nothing.

If you ever have a chance to compare the two pro drivers with a side by side camera, you'll always notice that the turbo driver will hit his gas Much sooner in or before the apex to get the turbo's to spool. so by the time he begins to exit, his turbo is at 100.

Personally, i would say Turbo. for one, your on a V8, and for even just a week-end warrior, we have alto of torque from 3-4grand.
Now I'll mention Gas. If your tuning it on 93/94 or race, and racing it often.. Even just 2$ a liter is still about 120$ fill ups.. And I'm, sure you know that going through 3tanks of gas on a full track day is easy to do, Even by following a 5Min on 15Min off rule. And what happens when it starts busting up to 3-4 a liter? (I'm scared ****less)

a con to a turbo. Well, hitting full boost at RPM, coming out of a corner.. my turbo beast has AWD, so its no problem. But i can only imagine that the RWD stang would just sideways.. Which is counter-productive to a fast lap-time. **Unless your in a drift-mania**

I don't have any troubles with some sticky tires, 94tune and a hot summer day. If i want to actually break it loose, then i have to give it the Scandinavian flick.