road course forced induction

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Well, I've never road raced, but my gut would tell me twin screw/roots-type. I would assume with having to turn and slow down a lot, you would mostly be in the lower RPM bands. Centrifugal S/C's and Turbos make most of their power up top, where as twin-screw and roots style blowers make it all through the power band.
 
Well, I've never road raced, but my gut would tell me twin screw/roots-type. I would assume with having to turn and slow down a lot, you would mostly be in the lower RPM bands. Centrifugal S/C's and Turbos make most of their power up top, where as twin-screw and roots style blowers make it all through the power band.

I have never road raced either but my gut told me that you could get into the gas earlier coming out of the corner without losing grip of the tires with a Turbo or even a Centifugal Blower.
 
It really depends on the courses that one intends to run. :D In my neck of the woods, Infineon and Thunderhill are good courses for a Turbo, while Portland International Raceway (PIR) and Buttonwillow are good courses for a TS SC. It depends on the lines of the track configuration.

PIR:

http://www.portlandraceway.com/map1.asp

Buttonwillow: (click on track maps for track configs)

http://www.buttonwillowraceway.com/

Infineon:

http://www.infineonraceway.com/images/facility_ama_irl_web.jpg

Thunderhill:

http://www.thunderhill.com/html/trackmap.html

One word of caution. If you want to run HPDE/HPDS events then you do not need to worry about the set-up. If in the event you look into joining SCCA fine. No way in the Grand Am series. No aftermarket forced induction allowed. You need to consult their rule books on set-up. Each is VERY specific to what is allowed/disallowed in modification.
 
I've road raced before
My opinion is for a smaller track use a screw type blower for more low RPM
torque. For this reason you will need to shift less, if it's manual that is.
and a turbo for higher RPM horsepower for tracks with longer straights.
 
In my humble opinion, you can use either. It just depends on how much power you want/need to make, and where you want the power. Just like Jenn said. But turbos don't need that much time to spool. If your set up is right you will notice little to no lag. Unless of coarse you want a monstrous amount of power. :)
 
Just curious, how much track experience do you have? I've read a lot online and I am keeping my '07 stock. Based on what I've read, you don't want a really fast or good handling car as a beginner.

I've been to 4 track days and have been signed off solo. I only plan to change things as needed. For example, when I get brake fade then I'll look at different fluid, pads, and maybe ducting.

When I can drive to the limits of the stock tires and suspension, then I'll consider upgrading.
 
Just curious, how much track experience do you have? I've read a lot online and I am keeping my '07 stock. Based on what I've read, you don't want a really fast or good handling car as a beginner.

I've been to 4 track days and have been signed off solo. I only plan to change things as needed. For example, when I get brake fade then I'll look at different fluid, pads, and maybe ducting.

When I can drive to the limits of the stock tires and suspension, then I'll consider upgrading.

Great advice. Doc - Houton is correct. One of the first things we are taught is "Know your Vehicle". Hours behind the wheel, learning the feel of the vehicle and the capabilities of it will lay the foundation for a great solo career. For the first 5 events you spend little time alone. Most is with an instructor and most the time you are driving less than 45-50 mph. It is all about technique and control and little to do with balls out speed and racing.

Houston - Have you run only the SCCA sanctioned HPDE/HPDS? Or have you had an opportunity to run open events as well?
 
It depends on the gearing, but professional road race teams use turbos, as ultimately you get more power out of the same boost/displacement ('course, top-fuel dragsters are SC...). With a properly sized turbo you can get a LOT of midrange torque.

World Rally Championship cars are 2.0l turbo, with a 32mm intake restrictor which limits them to roughly 330ish hp. They run over 300 hp from 3000 rpm up to 7000 rpm. Mind you, AWD helps with getting a 400 ft-lb kick in the butt in a 2600lbs car in the gravel.

For track days, get whatever you want. They're all fun, and they will all teach you traction limitations. :)

Tom