steve k. need help

[o2obsessed]

Steve,

I was reading some of your old posts about Suspension Springs. I was wondering how you like them and what spring rate you ended up ordering. How much did it lower you car if at all. Thanks.

Andrew

[steve k.]

I do like the springs. they seem a little heavy, but then i have never held a 500lb spring in my hands before.

i ended up runnign 500lb springs all the way around. My car is lowered, but how much? i don't know. But i run shortened struts in front and shorter shocks in the rear.

My shocks:

I also have an adjustable spring perch in the rear that allows me to rais and lower the car. I do run 8x5 springs that are almost as low as they can get. The car handles great on flat surfaces, but has a lot of bump steer on bumpy surfaces. I still need to figure out how to fix that and stay legal in class.

this is how low the car is on 215/50R13 tires.

let me know if you have any more questions,

steve k.

[Mike Self]

part by the stiff springs? I was taught that soft(er) springs with heavy sway bars and good shocks would give more compliance over bumps without excessive body lean in the twisties...

mike

[robspeed]

steve's is a dedicated race car, so he doesnt have to worry about compromizing. bump steer comes from lowering the car past its normal operating range, causing geometry problems. the fixes for this are to lower the pickup points for some of the suspension pieces (like steering arms) to go along with the lowered chassis. question for steve is whether this messes him up in the rules for his race class... (not to talk for steve, just saying in general)

[steve k.]

Rob is masically correct.

Due to the front end being lowered, the virtual controll arm now intersects the sterring arm thus causing the bump steer. It is always there, but only noticable on bumpy surfaces. The stiffer springs will bring it out more. Another reason it is very noticable is due to great toe out on front tires. It is a dedicated autocross car and runs mostly on very flat surfaces, so most of the time i do not care.

One of the way to correct this is by extending the strut bellow the spindle, but it is not legal in my class . I also do not think i'll be able to run 13" wheels after that is done.

The reason i do run springs that stiff is to elliminate most of the dive under hard braking. With wide race rubber and concrete surface cars really dive. I am still working on elliminating the lift of the rear tire during sweepers. Stiff springs and shocks helped a lot, but i think the next stepp is inicreasing the stiffness of the front sway bar. It is already mounted to the struts instead of controll arms, so i actually now have to find a different bar.

I am sure some people will recomend softening the rear bar to keep the rear tires on the ground, but I have tried that and that actually increases the roll of the rear of the car to the point when it lifts the tire even more. The car was orginally cornerweighed, but things had to be changed int he field to change the weight movement. Seams to be workign OK now, but can deffinatly improve.

steve k.