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Author Topic:   Front Suspension Setup ???
Dixon
Member
posted March 02, 2004 03:33 PM
This question is directed to everybody, but I'd particularly like to hear from people running Camaros.

I don't currently run a sway-bar (or anti-roll bar), but I've read a bunch of stuff about NASCAR teams using really light springs with heavy-duty anti-roll bars. I know that part of the reason they do this is to stick the nose as close to the ground as possible, but my questions are:

1)Has anybody tried this on dirt? I mean if you were running springs in the 1000-1300 range without a sway-bar then put one on and went to springs in the 400-600 range.

2) Does it work? I'm wondering if this helps the suspension in other ways then would be attributed to aerodynamics on CUP cars?

allan
Member
posted March 02, 2004 04:51 PM
I would realy like to know if itworks might be helpfull on my chevelle

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U LIFT U LOOSE


dirtracer50
Member
posted March 02, 2004 05:58 PM
I have played with sway bars alot on my camaro. I've never gone that light on my springs but my experience has shown that when you start messing with bigger sway bars they become real touchy. I think you may be able to make a setup like this work but you'll need a lot of different size bars and a lot of time to try and find the correct setup. Keep us posted on what you find if you try this.


speedyd1
Member
posted March 02, 2004 06:05 PM
think you would be asking for trouble if you went that light look at those cup car and see how they bottom out on some tracks with just the slightest bump an asphalt car is alot lower to the ground and doesn't roll as much in the corners as we do they also don't have to deal with ruts i have ran with and without and preloaded like speedy suggested i like without alot better


allzway
Member
posted March 02, 2004 08:13 PM
On my road course Camaro.... There is always much debate about which is better and there never is a consensus thought, but most on road courses run heavy springs and smaller bars. But those that do auto-x tend to like more bar and less spring.
Road courses are generally not tight and don't have as fast of transitions while auto-x's are usually tight turns and quick transitions.

I am not sure how any of this would relate to dirt...just giving you a different perspective and since dirt tracks are generally not a real fast transition, then it just might work.




Dixon
Member
posted March 03, 2004 01:34 PM
I didn't have any basis for the 400-600 spring rates other than hearing that CUP teams have gone to spring rates less than half of what they used to use. Since I run my front in the 1000-1300 range...

Dirtracer50, would you mind telling me a little more about your experience? I was counting on having to try multiple different bar sizes, but how much lighter did you go on springs?

c21
Member
posted March 03, 2004 04:11 PM
ia ma currantly running a 800 re and 1000 lf on my car with no sway bar.... and no prods ...i run at a 3/8's and a large 1/4


dirtracer50
Member
posted March 04, 2004 07:41 PM
Dixon, I'm not sure my info will help a whole lot I never really went very light on springs. I currently use a 950lf and 1150rf with a small sway bar. I only went down to 850 and 1050 on the springs with a larger bar. I use the bar just like speedyd1 explained to put crossweight in the car for a drier track. I've probably used five or six different sway bars with these spring setups and found that the larger bars were very unforgiving if they weren't adjusted just right. After causing and ill handling car several times I became frustrated and used the heavy springs with a light bar. I know that alot of people don't like the sway bar idea but it must be a driver preference thing because I wouldn't run with out one. Hope this helps some.


Scoot
Member
posted March 04, 2004 08:17 PM
How do you determine the size of sway bar? I run a 1200# rf and a 1000# lf. I've never ran a sway bar. I can get one off my old parts car which is a 75 camaro. Should I install it as you guys have described?

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Scoot
Smith Racing Team
870-365-5989


c21
Member
posted March 05, 2004 09:17 AM
keep in mind, that the rate of a torsion spring (which a sway-bar is) is determined by its length, lever arm length AND .... it's diameter to the 4th power. So ... (for example) a 1 1/4" bar has 2.44 times the rate of a 1" bar. ..... which may explain why some find bigger bars so unforgiving.

once you know a sway bar's rate (a fairly involved calculation), the effect a bar has on your roll resistance can be roughly calculated by determining it's wheel rate (which is a funtion of it's motion ratio)and noting it's significance relative to the wheel rate of your existing springing.

a rough calculation of wheel rate would be the distance between the lower A arm inner pivots and the center of the spring (or sway bar mount on arm) ..... DEVIDED BY the distance between the lower A inner pivots and the tire contact patch .... TIMES the rate of the spring (or sway bar).

c21

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