[torsen] Re: Aerodynamic changes...LONG...here we go....

Dave Hord spokes at mail.the-wire.com
Thu Nov 1 23:45:09 EST 2001

Ah...In the two books I've read on Race Car building/tuning they both talk 
about aerodynamics...but haven't mentioned the speed at which they become 

In my head i've been envisioning a semi 'splitter' (I'm probably using the 
wrong term)across the lowest point on the bumper.  Say, 6" in depth (front to 
rear), at the ends (where the bumper curves to the rear of the car) the piece 
would bend and move up the sides of the bumper on an angle. The idea being that 
some air will be forced to move across the splitter to the upturned ends on teh 
side of the car, offering some downforce.

But, as you mention, if this is only going to be effective at 50mph it's hardly 
worth it.

Do road course race vehicles rely on suspension and tire setups alone for the 
tight slow corners of a race course? Or does aerodynamics play a role?


P.S. If I had my dream, I'd have another 90q...slammed with a full carbon under-
tray with side skirts and brushes.  Effectively creating a large wing with the 
entire car...But, we must work with what I have!

Quoting John Petersen <petersen007 at earthlink.net>:

> I like the problem. Unfortunately you'll have to get to at least 50 mph
> (85kmh?) for aerodynamic forces to be at all worthwhile. From what I 
> understand from solo racing, this happens rarely. If I had a high speed
> car 
> for the track which I wished to do this with I would make something
> which 
> would look a bit like a snow plow too high off the ground, and at too 
> shallow an angle to be a snow-plow, and attach this to the lowest place
> where you have to get ventilation through. The device should not be so
> low 
> as to touch the ground in full-turn. Again, you'll have to be going
> ~70mph 
> (115kmh?) for this to work decently.
> The effects of dropping the car down to the ground can create an actual
> vacuum underneath the car, and with proper skirtings, can vastly
> increase 
> high-speed downforce. Note: proper skirtings will probably mean super
> stiff 
> springs and 1 cm clearance to the ground.
> Easiest idea: put stickier tires on the front. Works marvelously, I've
> done 
> it on my urS4, gone sideways down public streets like that
> (intentionally, 
> of course). Long lasting perf. tires on the rear, and quick wearing ones
> on 
> the front. That is my easy solution.
> Hope this helps you
> -John

More information about the Torsen mailing list