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Help on how to reduce drag

Help on how to reduce drag

Help on how to reduce drag

(OP)
Hello we are looking for info on how to reduce the drag on our race car.The car does 160mph in 8.8 seconds on the 1/4mile.

We now feel that we need to look at the aerodynamics for the car to go faster, the frontal area of the car is not very good,we also have to run with 3" ground clearance would a flat floor be the right thing to fit.

you will find photos of the car here

www.keithcowie.com

thanks team cowie

RE: Help on how to reduce drag

A fully bellypan would help, if it could replace something else, e.g. the original pan, so there's no net weight penalty.  Given that the original pan probably develops a lot of its strength from bends and corrugations, it's really not possible to just substitute a flat plate with no weight penalty.  Maybe you could stretch a sheet of mylar over the bottom just to try it.

While you've got the Sawzall fired up, turn it into a 7/8ths scale model of what it is now...  and of course don't park it near anything similar.

Mike Halloran
Pembroke Pines, FL, USA

RE: Help on how to reduce drag

Hi there 'team cowie'!
Nice R32 you got there..  At 160mph there is definately some aerodynamic effet coming into play.  A completely flat floor (in lightweight fiberglass or other) would definately be a start.  In addition, since you're only running the car in drag configuration, you should get rid of the front-mount intercooler (or is that your radiator?) and tape up all of the 'speed holes'.  Next step would be to fit wheel covers and finally, a row of shark fins at the top of the rear windshield to promote flow attachment (as fitted to the EVO).

good luck!

RE: Help on how to reduce drag

Teamcowie...

Goe to http://store.sae.org/

There are many books/papers on race cars, including aerdynamics [whole vehicle and details], stability and handling, etc...  

Regards, Wil Taylor

RE: Help on how to reduce drag

I agree with the bottom plate for the car, it seems high enough as it appears in your pics to allow for it, an while you're at it, have a look online at the ground effect Lotus 79 cars of the late 70s? You want something a bit different from just a flat plate on the bottom, but I don't know any useful details of what the special underplate looked like and how it worked, I only know about the skirts helping a lot. That was a very interesting and pioneering car, Lotus engineers would actually wrap bogus parts of the engine in a handkerchief and whisk them away when the car stopped at the pits to keep the other teams thinking that their amazing performance had something to do with the engine instead aerodynamics.

I don't know if it'd be sanctioned by your racing body or if the extra downforce would be helpful at all at a drag strip, but the lessened drag could help shave a few tenths of a second off.

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