CarmonColvin

Can you explain to us how removing the sway bar causes your springs to be stiffer?

I agree that having stiffer springs give a lower traction potential because of weight transfer. That does not mean you should try to find some 90lb springs because on most cars (including the FC) you need to have some stiffness to keep a desireable alignment. It is a tradeoff between keeping your camber/caster (front and rear) within reason and having too stiff of springs that increase weight transfer. And on the same theory a stiffer spring allows you to run a lower amount of camber for the same grip. The decreased camber increases your straight line accleration potential (rear camber) and increases your usable braking power (front camber).

I run (approx) 400lb springs in the front with a stock non turbo sway bar. And (approx) 275lb springs in the rear with NO sway bar.

swoop

Removing the sway bar does nothing to your spring stiffness.

But will you agree that you need to run stiffer springs to compensate for removing the sway bar?

You want your car to run as flat as possible through corner. Right? If you're not trying to do that then I think you are going in the wrong direction. Most race cars I know run sway bars to resist body roll, or a complicted 3rd spring set up.

But if you feel your setup is right, good luck.

kristopher_d

on a bumpy surface.

Stiffer springs actually reduce weight transfer. As a spring extends, weight is obviously being transfered away from it. As a spring compresses, weight is obviously being transfered to it. Since inertial load increases faster than traction as weight increases, it is best keep loads as balanced as possible. Sway bars use simple balance to prevent excess body roll. As weight is transfered to the outside spring and it compresses, it forces the inside spring to compress when it would rather extend. This furthere reduces weight on the inside wheel, thus reducing traction. By removing the sway bars, you allow the springs to do their job more effectively. However, it does require stiffer springs to compensate for the increased tendancy for body roll. That was the purpose of my initial post. I wanted (and still do want) to determine arithmatically (okay, trigonomically) the spring rate required to keep body roll in check while allowing both of the rear wheels to achieve optimum traction, rather than stealling traction from the inside whell to reduce body roll.

C. Ludwig

iTrader: (27)

Not trying to be a smart *** but have you listened to anything I've said? Seriously. Does it not make sense? You're trying to re-invent a wheel that has been rolling for nearly 20 years. If the effort the Mazda Factory put together for IMSA in the 80's didn't turn it up you ain't gonna find it. If you want a setup all you have to do is call Mazdaspeed and they'll suggest something that will put you in the ballpark at any track in North America. Not a flame just a reality check.

If you wanna do the math it's obvious we're not going to be able to give you the rates you need to work the formula. Again, Mazdaspeed, Racing Beat (if they have any engineers left from the 80's) or Ground Control would be a good place to start.

Also you view of a sway bar is flawed I believe. Springs store energy. And that's what a sway bar is doing as it is a torsional spring. As the coil springs and sway bars resist roll they store energy. A sway bar does not force the inside spring to compress. The only thing it is doing is storing energy that would otherwise be transferred to the outside springs.

One more time for everyone.
1)It's OK to run without a rear bar. You're not going to die trying.
2)All the authors I've read discourage what you're wanting to do.
3)You are NOT lifting the inside rear tire.
4)The diff and lousy tires are most likely your problem.

Oh yeah, race tracks are bumpy. And if you're not making the car go through a serious bump cycle you ain't driving it hard enough.

Chris

swoop

Maaaaan, there are alot of misconceptions and misinformation here. Sway bars do lift the inside wheel. But they give more traction than they take away.

jeremy

iTrader: (1)

i'm going with swoop here on the lifting of the wheel. it is possible as the swaybar is controlling the difference in height between the two connected wheels. if the front bar allows more difference then the rear bar, the car will be able to pick up the rear tire. however, as chris is saying, this is not the road you should be going down. your problem is more related to not having a lsd an crappy tires. taking off your sway bar is a bandaid fix. get an lsd, better tires and then use removal of the swaybar and other suspension tuning to balance the vehicle. you can't point at the swaybar as the problem unless you know what is behind it, causing it to happen.

CarmonColvin

Removing the rear sway bar is NOT a bandaid fix!

My car has a competition LSD with 4.33 gears with very low mileage and race tires as well.

I have removed and installed various rear sway bars in combination with different front sway bars. (RB Front and Rear; RB Front, Stock T2 bar rear; RB Front, Base bar rear; RB front bar, NO rear; Stock T2 Front, NO rear (current setup)). Everythign but the shocks on my car is top notch with plenty of time invested on an alignment rack and corner scales.

You may be thinking "What does he know?". Go hang out on ImprovedTouring.com and see what the top ITS cars are running.

kristopher_d

Well guys, simply for competive reasons, I'm shelving the no rear sway bar idea. I don't have the cash to make my car competitive in prepared class, and that's where I would have to run if I removed the rear sway bar. I'm sticking with the stocker in back, because it's required for Stock and Improved classes. Eventually I'll get my car where I want it, but I've got other bills to pay for now.