Need some advice on coil over lbs rating?

Can anyone give me some advice on what coil overs to use on my A model tudor (sedan)
I am running a triangulated 4 bar on a fabbed chassis,fuel tank in the rear.
Not really concerned about handling,just want to know what pound rating I should run-200,250,300?????
Any advice will be greatly appreciated!
El-richo.

 

Depends on how much wieght is on the rear end and what angle the shocks are at.

For a wieght of 1350lbs on the rear of the car with the shocks near vertical, 300lbs per inch will put you if the ballpark.
900 lbs on rear will take you down to needing about 200lbs per inch.

 

I will be running the shocks at about 30 degrees-roughly.

 

For 30 degrees increase the spring rates by 15% for the same vertical load

 

A recent thread,,,this might help. HRP

http://www.jalopyjournal.com/forum/showthread.php?t=403224&highlight=coil+overs

 

I was told 220# at 28 to 27 degrees..on a Tudor A

 

I would probably look at 250's I just went through the same thing mine are on less of an angle and a 32 tank out back. I had to change mine to 300's from 250 ride is stiffer but the handleing is better.

 

Drop it down to about 150-175, it will ride good and hook up better

 

How much travel do you have in the shocks? Many guys use short travel shocks and get stuck having to run real stiff springs to avoid hitting the snubbers all the time. Before you buy them, check with the seller and see if they will let you exchanged them if they are wrong. It seems like most guys that use coil overs end up with some extra springs in the garage.

 

Whatever you do, do not use the Speedway catalog charts. Ask a shock manufacturer.

The Speedway charts said 300 lbs for my 1933 Willys sedan rear (V6 turbo/TH 350 Vette IRS 1525 lbs rear weight full tank unladen, 30 degree shock angle). The shock manufacturer (Carrera) said 550lbs. Guess who was right....

 

I had almost exactly the same experience. Using Mark VIII IRS in '28 Tub. Speedway was way off. I think I have 500LB, that was the 3rd set I tried.

 

Sounds like I will need about a 400 pound spring rate then.
OK then-who makes the best ones???????

 

alden is a nice brand for coil overs

 

http://www.proshocks.com/calcs/anglefirst.htm

Here is the calculator I used....Dave

 

The pickup in my avatar weighs 2380 and my coilovers are mounted @ 30 degrees. Everyone told me I needed 200# springs. The truck rode like a buckboard...people following me down the highway commented on how much air I was getting under the rear tires! I called up an All American coilover distributor (cant remember who, its been about 10 years) and he suggested I run their 180# progressive rate coilovers. They were perfect right out of the box...truck rides like a dream and the rear tires stay on the ground!

 

I tried 300s, and they were pretty stiff!!
So-After the rebuild Im gonna try 250s-see how that goes.
Im using So-Cals speed shocks.

 

I used pro shock calculator it is always close used #120 vertical on a 4link 61 corvette with 9" stroke shocks built others I call the tech at pro shocks. you have to watch your shock rate too stiff and the springs don't work and will ride hard you need them just stiff enough so the car doesn't bounce

 

I like AFCO for springs. They're very reasonably priced and guaranteed forever, not only against breaking but also against loosing tension.