5th coil / chassis's traction control devise

[ShortTrakWarrior]

ive been told that the lift bar and 5th coil is a built in traction control devise.

ive been doing a lil reading on this subject. from what i read and am able to comprehend. there is no correct recomended preload measurement on the 5th coil. unless engine, gear,and tire rule is figured in. ive been told before by an unreliable source that all cars should be set at 1/4 inch preload.

from what ive read now. it is my understanding that if your preload is too high you will experience the tires spinning. therefore if you were to reduce the amount of preload on the 5th coil you would get more traction. has anyone found this to be true?

or should u just change the spring rather than adjust ur preload?

also what happens when u increase or decrease the spring rate on the 5th coil. which one gives more traction.

the reason im asking is because the track i run on is always super slick and i never seem to have the grip and this is an area i never messed with. im on hard azz skinny lil spec tire rule that dont help my situation.

any info about things yall have done with ur lift bar / 5th coil to improve traction would be info greatly appriciated. like ive said before im not the brightest bulb in the pack, so im more of a this does this, that does that, type of learner. with out all the complicated responses that i would need a engineering degree just to understand lol. no offence to you smarter folks lol.

thanks a ton

[billetbirdcage]

You'll probably get several different answers as alot depends on the driver.


Generally if you not real smooth with the throttle you will likely have better traction with a softer spring rate, but a driver that is real smooth will generally like a stiffer spring.

A stiffer spring hooks up quicker but doesn't stay hooked up as long and the opposite for a soft spring it hooks up slower but stays hooked up longer.

If I had a soft spring in the arm like a 200, the car was so slow to hook up that you couldn't ever get the car going off the corner that even if it would hook up better later down the straight you were still loosing time.

I went so far to installing a hydralic jacker on the fifth coil to increase the preload while on the track (test day). With a 200# spring in the torque arm and a 1/4" preload instead of a 300# spring, I couldn't keep up with the other cars that I easily out ran everyweek. So I cranked a full 1" of preload in the spring while still on the track and then I could at least stay with the other cars. Came back in and replaced with the normal 300 spring and when back out and passed them like normal.

If you go too stiff for you smoothness on the throttle you can shear the contact patch and then loose traction.

For the most part I wouldn't ever use anything softer then a 300 and may get as high as a 425 but keep in mind that the closer to the rearend the fifth coil is mount the softer the spring rate acts. So a 350# at 32" out will act similar to a 300# at 38" out.

[ShortTrakWarrior]

Question 1
did you have too much traction that bogged your motor down or not enugh traction and spinning with the 1/4" as the reason you weren't keeping up, you answered most of my ?s perfect except for did more preload give you more traction or less?

QUESTION 2
is adding preload similar to stiffening the spring but to a much smaller degree?

QUESTION 3
with out me having to put my car back on the scales. could you tell me how more/ less preload effects the scales as far as percents or pounds?

thats all the questions i can think of right now but give me a few days and im sure ill be askin somethin else lol


i hope too many people dont have different oppinions on this or i will be confuzzled all over again lol

thanks for your help, it is greatly appriciated. if there were more of you, the world would be a better place.
i ask questions on here because when u ask locally you dont know if they are out to help or hurt ya.

[billetbirdcage]

#1. I couldn't get into the gas or it would spin the tires - lack of traction.

#2 Yes, in a way!

#3 For the most part, it will not change the scaling of the car as far as percentages but it may alter LR bite a few pounds but nothing to worry about.