i normally race in the mid-west were the altitude is around 1,100 feet.
i have a race this weekend at high plans raceway that is at 5,000 feet,
will the ring wing need more angle and or should i soften the spring rates?

 

Very interesting question! I've never even had to think about this... pretty flat where I live! I'm sure someone with some aeronautics knowledge will chime in with some good information. My initial thought is that you'll get less downforce from the wing (at the same AOA) in the lower-density air... less drag and less lift as well though. How does that affect the overall balance of the car? And will the wing stall at a lesser AOA than it would at a lower altitude?

I guess if it were me I'd do one of two things; 1) Leave the car as is and if it feels loose in practice, dial some more angle into the wing. 2) Change to a softer rear spring since we know that won't be affected by the altitude change.

I'm interested to here what other, more knowledgable persons have to add.

BTW, glad to hear you're getting the car out on track again. Wish you could have made it to Putnam in October!

And if all else fails: http://www.sciencedaily.com/releases/2006/...60624120556.htm

 

I'd never really heard of this idea until a couple weeks ago when I was watching one of the races on speed... Rolex I think it was. They mentioned that wherever they were racing was at a high altitude and all the teams were running their extra high downforce setups. Makes perfect sense.

Can you adjust your front downforce? If not, I'd just leave the wing settings alone to keep the high-speed/aero balance the same. If you've got the car setup to be oversteery before aero kicks in and then the opposite after, might not be a bad idea to go to a softer spring in the rear for a little more high-speed stability.

I'd probably be more worried about how the tune with your supercharger is gonna act, or is the ECU pretty good about auto-correcting for that?

 

That would explain the HUGE wings on the Pikes Peak Hill Climb cars...

 

Good point! John, you now know what you need to make your car look like for this upcoming race. Just buy 6 or 7 cheap ebay ricer wings and bolt them to the car in as many places as possible.

 

Does that mean you have to take points for all of them?

 

HPR is a very fun track with lots of elevation changes. Hopefully you're running Saturday because Sunday is possible snow.

 

only thing i can say is car will feel slower. higher altitude is less dense air for the motor

car will feel like a slug compared to the 1000ft elevation.

 

before i left to go to high plains raceway i just installed some new aero, apr 67" rear wing with gurney lip, apr front bumper, spliter and there new S2000 canards (which fit and look great) , so i had no reference point to start with. i ended up lowering the car about 1/8" (most i can do without rubbing the insise of the front fender wells. the car was low on power , but since it is supercharged it seams much better than the other N/A cars there. i had to put 12 degrees in the rear spoiler, tweak with the shocks & front swaybar settings. already had soften the spring from 18K front & 16k rear. to 16k front & 14k rear. over all the car felt good. i started P1, finshed first and set and new track record in STO. this track has the most elevation change in 1 lap (300 ft change per lap) in it's 2.5 mile corse set-up. it's fun, fast and busy.

p.s. arron i think that pikes peak car aero set-up would look good on your car

 

Looks who's talking!

Its great to hear the car ran well for you. Congrats on the STO record! I'll be looking forward to seeing the car in person again, even if its just a speck in the distance on track!