My TC Kline suspension is coming on Friday. I was curious what are good base settings for rear and front ride height and bump and rebound settings to start out with. I would imagine there must be a thread setting that is pretty standard. Also is it worth it to get the car corner balanced right away? I have read some things in the Skip Barber book that lead me to believe that corner balancing may be overated.

I have read some things in the Skip Barber book that lead me to believe that corner balancing may be overated.

You sure you read that correctly? :rolleyes

I just read it again page 211 and 212 of "Going Faster". It states changing the spring perch ride height only accomplishes changing the ride height and doesn't change the static load on the tires. They claim the only way to balance the weight is to move components on the car.

Take this all with a grain of salt, as I have less than a week of experience with my TCK D/A. The best solution is to call Pete Stackhouse at TCK and get exactly his suggestions for exactly your car, spring rates, sways, driving style, etc. These instructions are from TCK.

Springs: 450 front 500 rear

Ride Height: "Set front of car with 1/2" to 5/8" of thread showing below the ride height adjuster lock ring. Measure from rocker panel to ground at a common point on the front of the car and set the rear 3/4" higher."

Shocks:

Rebound Front full firm -1.25 turns Rear full firm -1/2 to 3/4 turn
Compression Front full firm - 8 clicks Rear full firm - 5 clicks

Sway bars: Front full firm to medium firm. Rear medium to medium soft

Having driven it a bit, I wanted a bit less rebound in the front, so rebound is now -2 turns off full firm

My car is understeering a bit, but with spacers and equal size 235's Toyos all around I suspect it will be very neutral.

I talked to Bill at Soul Speed and Pete both gave similar advice. So how do you like it so far? I am putting 500lb fronts and 600lbs rears. That was Bill's recommendation and Pete agreed.

Ride Height: "Set front of car with 1/2" to 5/8" of thread showing below the ride height adjuster lock ring. Measure from rocker panel to ground at a common point on the front of the car and set the rear 3/4" higher."


For what it's worth, the stock rake difference on the car is 3/4" lower in the rear. So Pete or whomever said that has that backwards. Unless that's really how they setup their cars, I'd keep the stock rake difference though.

-Carlos.

I just read it again page 211 and 212 of "Going Faster". It states changing the spring perch ride height only accomplishes changing the ride height and doesn't change the static load on the tires. They claim the only way to balance the weight is to move components on the car.

Well, the easiest test is go put your car on the scales, and raise one perch up/down, I garuntee all the corner weights will change.

Also, with higher spring rates used for racing, you'll notice a difference more with slight height changes.

This is also why there are weight jackers, so you can tune the chassis by varying the ride height at a corner...moreso for circle racing, but still same concept. By varying the height you are varying weight distribution onto the tires, hence changing handling characteristics.

You can't shift weight between axles or sides, just diagonal.

And note that 50/50 weight distirbution is not always desired.

Its kind of like blueprinting an engine in a sense. While it might not be worth much by itself, it plays a roll down the road. If your corner weights are all whacky, and you try to tune your suspension, you are taking one step forward and 5 steps backwards.

There's a reason accurate scale setups are expensive, and often custom made for high end applications where being precise and accurate are worth the money.

And regarding rake...OEM design is intending for slightly different purposes than a race/track car. OEM, even very "sporty" cars are designed to slightly understeer if anything on the street. But on the track in a racing environment, that might not always be preferable.

And regarding rake...OEM design is intending for slightly different purposes than a race/track car. OEM, even very "sporty" cars are designed to slightly understeer if anything on the street. But on the track in a racing environment, that might not always be preferable.

So what do you recommend for an initial setup for a DIYer? I'm gonna swap in tckline c/o's over the weekend also and was going to set the rake to the stock one. As for initial height I was going to keep the current one with Eibach Prokits, it's not too low not too high and handles decently on the track. Mine is definitely a compromised setup as I want to still be able to drive the car on the street but yet handle a little better than with the Prokits.
I'll get it corner weighted when I can get on some scales.

-Carlos.

For what it's worth, the stock rake difference on the car is 3/4" lower in the rear. So Pete or whomever said that has that backwards. Unless that's really how they setup their cars, I'd keep the stock rake difference though.

-Carlos.

Sorry 'los, but you are going to want some rake in the car and what Pete said is a good starting point.

Mike

Take this all with a grain of salt, as I have less than a week of experience with my TCK D/A. The best solution is to call Pete Stackhouse at TCK and get exactly his suggestions for exactly your car, spring rates, sways, driving style, etc. These instructions are from TCK.

Springs: 450 front 500 rear

Ride Height: "Set front of car with 1/2" to 5/8" of thread showing below the ride height adjuster lock ring. Measure from rocker panel to ground at a common point on the front of the car and set the rear 3/4" higher."

Shocks:

Rebound Front full firm -1.25 turns Rear full firm -1/2 to 3/4 turn
Compression Front full firm - 8 clicks Rear full firm - 5 clicks

Sway bars: Front full firm to medium firm. Rear medium to medium soft

Having driven it a bit, I wanted a bit less rebound in the front, so rebound is now -2 turns off full firm

My car is understeering a bit, but with spacers and equal size 235's Toyos all around I suspect it will be very neutral.

I have this setup (TCK D/A) and 500f/600r with camber/caster kit in the front, camber rods in the rear and eibach sways. Pete gave me about the same recs he gave Scotty (with a little less rebound). I found that it wasn't enough rebound because my car seemed to sway in a very unpredictable manner on turns..almost felt like I was driving a marshmallow on a very firm suspension. Of course rebound is not supposed to control overall sway (that's the function of the swaybars), but it'll affect how quickly it transitions. I increased the rebound some (both front and rear) and this helped.

At VIR I ran into a member of this forum who was good enough to help me dial in a bit more understeer. His name on this forum is McClaskz or something, and he sent me these two diagrams which are FANTASTIC in assisting setting up suspension:

http://filebox.vt.edu/users/chcampbe/OVERSTEE.gif

http://filebox.vt.edu/users/chcampbe/UNDERSTE.gif