What should I be using for rear coil springs ?

[wikd69]

Ok, so here's a question.

My Camaro is 3845 lbs with me in it. I know, it's a porker, but it is a street car

I just installed QA1's in the front with 550# springs (these are the QA1/R version, not the street version)

I currently have Alston single adjustable coilovers in the back with 135# springs.

This is a back-half 32" ladder bar car. All steel big block, TH400, lots of weight.

I've not had a chance to scale it yet, so I don't know how the weight is distributed.

My question is this: I have two sets of coils for the back, 135# and 185#. What would you recommend ? The new QA1 are essentially teakable 90/10 shocks, so there'll be a lot of weight shifting to the back of the car under throttle.

Are the 135# coils too light ? Are the 185#'s too stout ? I could get some in the middle, but I consider these two the extremes.

I know theres not a lot to go by, but I don't know what I should be stuffing under the back.

[supernova]

Herry,
The rule is use the lighter spring and put alot of preload on it . If you use to stiff of a spring then you don't put much preload on it. That causes it not to store enough energy to make the suspension work properly. The lighter spring will need more preload to support the back of the car and will store more useable energy.
Hey get Dave Morgan's book and that should help you out a lot. I think it's called: Door Slammers: The Chassis Book

It is always better to error on the lighter side when springing a drag car. I would stick with the lighter springs to start with and preload them.

Just my 2 cents

[wikd69]

Herry,
The rule is use the lighter spring and put alot of preload on it . If you use to stiff of a spring then you don't put much preload on it. That causes it not to store enough energy to make the suspension work properly. The lighter spring will need more preload to support the back of the car and will store more useable energy.
Hey get Dave Morgan's book and that should help you out a lot. I think it's called: Door Slammers: The Chassis Book

It is always better to error on the lighter side when springing a drag car. I would stick with the lighter springs to start with and preload them.

Just my 2 cents

okie doke :)

I'll chase the book down too.

Thanks Chris

[Bob West]

My Camaro is 3845 lbs with me in it.

I've not had a chance to scale it yet, so I don't know how the weight is distributed.

Now that I'm thoroughly confused.

[wikd69]

My Camaro is 3845 lbs with me in it.

I've not had a chance to scale it yet, so I don't know how the weight is distributed.

Now that I'm thoroughly confused.

I've weighed the machine, just not corner by corner, that's what I meant...

I don't know the weight distribution front to rear, nor left and right.

I just know that with the cheeseburger munching meathead in the left seat, it weighs about 3850.

[Yellowchevelle]

Herry,
The rule is use the lighter spring and put alot of preload on it . If you use to stiff of a spring then you don't put much preload on it. That causes it not to store enough energy to make the suspension work properly. The lighter spring will need more preload to support the back of the car and will store more useable energy.
Hey get Dave Morgan's book and that should help you out a lot. I think it's called: Door Slammers: The Chassis Book

It is always better to error on the lighter side when springing a drag car. I would stick with the lighter springs to start with and preload them.

Just my 2 cents

X2 go with the lighter spring and put some preload in them