swaybars and corner exiting accelleration

[NSX_GTR_LM]

I notice after the full set of hotchkis sways I can get on the throttle much more when exiting a corner. Is this because the desired hop in the inside wheel is counteracted with weight transfer from the swaybar? taht is my educated guess, can someone correct me if i am wrong?

[GTS LAID]

the reason is actually kinda simple and it has to do with weight transfer / distribution, and lift on the inside wheel.. with less lift you're getting a higher normal force on the tires... increasing your available friction per tire (even if overall is the same the distribution is much better) and therefore its acting as a crude LSD of sorts by distributing the power more evenly. thats MY guess

[NSX_GTR_LM]

thats my guess too, just stated a bit more eloquently :) Thanx for the timely reply.

[GTS LAID]

now i cant wait to be provem wrong by a suspension guru...lol

[nxracer]

I have actually found that attempts to increase front roll stiffness also increase wheel spin. It seams the stiff front end tends to "lift" the inside front tire under high cornering loads.

[4PASNU]

Originally posted by nxracer
I have actually found that attempts to increase front roll stiffness also increase wheel spin. It seams the stiff front end tends to "lift" the inside front tire under high cornering loads.

But if you use the stiffest setting for the front bar and have a LSD?

Dan

[nxracer]

An LSD will help BUT it will not keep the tire on the ground.

[NSX_GTR_LM]

is it that it tends to lift the inside tire under the same cornering load, or that the threshold is so much higher that it causes the inside tire to lift. If our tires had infinite traction, all inside tires would lift, and eventually roll. Is it more of a case of the higher threshold causing the inside tire to lift?

[nxracer]

I really don't think so. Stiffening the car will increase wheel lift no matter the cornering force, did you know that making the "rear" bar too stiff will also lift a "front" tire. IMHO anything that promotes lifting the front tire on a front wheel drive car is a bad thing, maybe a LSD will mask the problem but it will still be there. The key is finding a way to increase roll stiffness without stiffening the front bar (see below for the answer). I have ran with a stiffer bar and have had mixed results. with the bar stiffer I love the way the car turns in and runs down slalom's but coming off sweepers really sucks. Being able to "put the power down" is much more important to me than a couple mph in a slalom.

Some things I really believe about car set up
1. 25% of the improvements you make to your car will slow it down.
2. 25% of the well thought out changes you make will improve your time just a little.
3. The rest of the changes will not make any difference that you'll notice.
4. (and this is really #1) Just drive the car better, actually drive it the way it "wants" to be driven. A Happy car is a fast car.


An excerpt from A Basic Guide to Dialing-In Your Car (http://www.tsscc.org/images/handling.pdf) By Alex Tziortzis

snip...
I will discuss springs and swaybars together. Springs and swaybars work in tandem with each other during a cars transition and steady state handling (see Appendix A). Both affect body roll of the car as well as weight transfer. A stiffer bar can often be put on a car to keep body roll in check, especially if the springs are soft. Conversely, stiff springs can be used to control body roll and smaller sway bars used with them. Which is better and why do you want to control body roll? I prefer having stiff springs and a smaller sway bar than the reverse. This is because a swaybar effectively makes the suspension on that end of the car dependent (instead of independent). This means, in order to control body roll, a sway bar will tend to lift the inside wheel in a corner, making what happens on one side of the car dependent on the other. By using springs to control most of the roll, you keep the suspensio n more independent from side to side. The reason you want to control roll is that body roll is a significant factor in weight transfer. While you do want to have some weight transfer (this is because a tire grips better laterally with more vertical load), at the same time too much weight transfer decreases vertical load on the inside tire, making the outside tire do more work to keep your car turned. Cars that roll little are best. But there is such a thing as too stiff. If the car is too stiff it will skip over bumps and deformities in the pavement as well as possibly load the tire under cornering too fast, causing the tire to break away and slide.
..snip

[NSX_GTR_LM]

I agree totally with what you are saying now. I have noticed that long sweepers can be a beeatch. I also understand everything in the article, but there must be some weight transfer. How do we know what is best?

[Patches]

With front wheel cars, you want the rear stiffer. With rear wheel you want the front stiffer.

If your front tire is lifting completly off the ground, the front is to stiff or the rear is to soft(for a front wheel). You, of course don't want you wheel to lift completly off of the ground, but just touching it.

This info I took out of a book on suspension setup and racing.

[nxracer]

Originally posted by NSX_GTR_LM
How do we know what is best?

That's were testing comes in

"Glad I run stock class"

[GTS LAID]

actually i agree with nxracer... too stiff a setting will lif the entire corner up.. but you are changing the thinking from wheel and tire loading dynamics to entire chassis load dynamics... of course the second will give you a better idea.. but since its more general its also harder to figure out...

[t2000gts]

but why can you then get on the throttle more while exiting a corner?

also, can you corner with greater speeds (as opposed to actually cornering faster) with a sway bar? i'm making this up off the top of my head but if the inside wheel(s) are lifting, then the outside are being pushed down, meaning bigger contact patch, along with the weight transfer to that end, meaning an overall increase in traction...and here is where i have no idea at all what i'm talking about...since the outer wheels spin faster than the inside wheels when turning (assuming you don't have an LSD), the outer wheels will spin faster than they would on a stock car, and since the inner wheels are lifted, they won't have enough friction to mess with the speed of the outer wheels? (also less chance of actually starting to slide?)