Autocrossing + Surprise Visitor

370zDR · 05-16-2012, 09:06 AM

Quote:

Originally Posted by ResIpsa

I actually was going to comment on this but decided on my previous snarky comment. Take a look at your photos. You will notice that your outside front and rear tires are lifting at about the same rate. Ideally, you want as much rear traction as possible when auto crossing our cars. That means keeping those rear tires as connected to the pavement and getting the outside front tire to the point of lifting off the pavement.

I would suggest full stiff in the front and full soft in the rear. This would give you maximum grip when throttling out of corners. 0threefiftyz runs the massive Hotchkiss front bar and no sway bar in the rear. And he won the Tire Rack Solo Nationals in BSP.

I'm not sure if I'am right, but You mean getting the INSIDE front tire to the point of lifting off the pavement??, isn't the outside tire the one getting the load?. As if I'm turning right, left tire would be the outside and getting loaded, right front tire would be inside and be the one lifting. Or do I have the whole outside/inside tire backwards??

Have read if you run very stiff front, You'd have oversteering issue. Looking for street/track setup

ResIpsa · 05-16-2012, 10:17 AM

My mistake. Yes I meant the inside front tire.

ResIpsa · 05-16-2012, 10:48 AM

Generally accepted rules: 1) Stiff = less traction, 2) Soft = more traction, 3) every input on a tire reduces overall traction (deceleration, acceleration, turning) and 4) you want to be on the throttle as soon and hard as your car can handle when exiting a corner.

Take a rear wheel drive car with a very stiff front suspension (in relation to the rear) around a corner with no throttle and it will under steer like a dump truck. Why? All the traction is with the rear tires and the front tires tend to continue traveling in the direction of the rear tires (straight ahead and not around the corner).

Then why is a very stiff front suspension ideal when this logically creates under steer?

Look at rule 4. You are going to compensate for the under steer as you apply the throttle out of the corner and thereby reduce available traction to the rear tires. This allows the car the maximum available traction to the rear tires and the fastest speed out of the corner.

05-16-2012, 10:17 AM	#2 (permalink)
ResIpsa Track Member Join Date: Apr 2009 Location: Virginia Posts: 564 Drives: 09 RACING HEN Rep Power: 340	My mistake. Yes I meant the inside front tire. __________________ The Reed Law Firm; Michael Fasano VA Attorney and Counselor at Law: A Virginia Traffic, Criminal, and Family Lawyer.https://reedlawva.com/

05-16-2012, 10:48 AM	#3 (permalink)
ResIpsa Track Member Join Date: Apr 2009 Location: Virginia Posts: 564 Drives: 09 RACING HEN Rep Power: 340	Generally accepted rules: 1) Stiff = less traction, 2) Soft = more traction, 3) every input on a tire reduces overall traction (deceleration, acceleration, turning) and 4) you want to be on the throttle as soon and hard as your car can handle when exiting a corner. Take a rear wheel drive car with a very stiff front suspension (in relation to the rear) around a corner with no throttle and it will under steer like a dump truck. Why? All the traction is with the rear tires and the front tires tend to continue traveling in the direction of the rear tires (straight ahead and not around the corner). Then why is a very stiff front suspension ideal when this logically creates under steer? Look at rule 4. You are going to compensate for the under steer as you apply the throttle out of the corner and thereby reduce available traction to the rear tires. This allows the car the maximum available traction to the rear tires and the fastest speed out of the corner. __________________ The Reed Law Firm; Michael Fasano VA Attorney and Counselor at Law: A Virginia Traffic, Criminal, and Family Lawyer.https://reedlawva.com/

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