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Old 10-01-2012, 05:30 PM   #1
leecea
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Default Question about rear grip: mechanical versus aero

I was at a very slalom heavy event this weekend and watched the top drivers pivot their cars around like pendulums. They must have set their cars to be very loose, presumably by reducing mechnical grip at the rear. Yet a number of them are running rear aero. Seems like they're taking away mechnical grip and adding aero "grip"

Is the goal to set the car very loose for slow speed turns, then use aero to try and plant the rear end at higher speeds?
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Old 10-01-2012, 06:02 PM   #2
NSFW
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Sounds like a plausible theory.

But don't forget front end setup - getting camber and caster dialed in will also help with turn-in and rotation.

And don't forget weight transfer, i.e. driver mods.
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Old 10-01-2012, 06:12 PM   #3
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It's possible that aero is being used to try and calm the rear down in higher speed segments, but more likely the car is just set up loose and the driver uses it to flick the car in tight stuff and is very cautious in the higher speed stuff.

Some say that mccanixx sets his ESP car up to spin while still in grid.....

Jay
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Old 10-01-2012, 07:48 PM   #4
leecea
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Thanks. Yes, these were drivers who are on the top of their game, with very well sorted cars. I'm just curious about how they set up their cars.

I know car set up won't fix my problems.
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Old 10-01-2012, 08:59 PM   #5
speedyHAM
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Quote:
Originally Posted by leecea View Post
I was at a very slalom heavy event this weekend and watched the top drivers pivot their cars around like pendulums. They must have set their cars to be very loose, presumably by reducing mechnical grip at the rear. Yet a number of them are running rear aero. Seems like they're taking away mechnical grip and adding aero "grip"

Is the goal to set the car very loose for slow speed turns, then use aero to try and plant the rear end at higher speeds?
This is exactly how I setup my XP car. Running a big rear wing allowed me to drop rear camber .2 and increase rear toe out by 1/4" to get the car to rotate like an M3 on the throttle.
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Old 10-01-2012, 08:59 PM   #6
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Quote:
Originally Posted by Storm View Post
It's possible that aero is being used to try and calm the rear down in higher speed segments, but more likely the car is just set up loose and the driver uses it to flick the car in tight stuff and is very cautious in the higher speed stuff.

Some say that mccanixx sets his ESP car up to spin while still in grid.....

Jay
I just spit up my soda...ROFL.... Thanks Jay..


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Old 10-12-2012, 07:57 AM   #7
penderperson
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Quote:
Originally Posted by Storm View Post
It's possible that aero is being used to try and calm the rear down in higher speed segments, but more likely the car is just set up loose and the driver uses it to flick the car in tight stuff and is very cautious in the higher speed stuff.

Some say that mccanixx sets his ESP car up to spin while still in grid.....

Jay
I heard this in the voice of Jeremy Clarkson as I read it...
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Old 10-13-2012, 11:08 PM   #8
Butt Dyno
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Quote:
Originally Posted by Storm View Post
It's possible that aero is being used to try and calm the rear down in higher speed segments, but more likely the car is just set up loose and the driver uses it to flick the car in tight stuff and is very cautious in the higher speed stuff.

Some say that mccanixx sets his ESP car up to spin while still in grid.....

Jay
He must have amped it up since STX..

http://forums.nasioc.com/forums/show...9&postcount=59
Quote:
Originally Posted by mccanixx View Post
Great thread. I applaude you for taking the time to chronical all of this, it seems it would be a benefit to all others walking the same path. (subaru on street tires)

As far as a loose car. I would recommend that you'd want the car to have the potential to spin on your way to the start line. From there dial your inputs back on the steering wheel.
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