• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Coil spring help

desertjr

NAXJA Forum User
Location
Low Desert
Picked up some coil springs from a member. He said they were RE3.5" but I'm not sure..the part number on them is rm60120-59911.
I'm trying to figure out overall lift & spring rate on them!
 
FOund it using only the first half of the part #. They are RE 3.5, 190lbs spring rate.

Now if I cut off 1 full coil how much will that spring rate go up?
 
Cutting will always raise the rate, progressive or not. If they were progressive the spring rate would not only be higher but ramp up quicker as well.

If you have 2 coils, same everything except free height, the shorter coil would be stiffer always. Yes there's reason, yes I understand no. N I won't type it out as I'm on my phone lol.
 
I know what you mean, cutting the spring simply reduces the amount of metal available to absorb the shock.

Spring rate is generally measure in lbs per inch. It takes x lbs to compress the spring one inch.

A rough estimate would be to count the coils, and divide by 100. That will give you essentially what percentage of the load each coil absorbs.

Say you have a spring with 12 coils. Each coil you cut off will increase the spring rate by approx 12%. Not sure how many coils are in the RE 3.5" spring, but since you have the stated spring rate, you can easily get a rough estimate of how much stiffer it will be when cut.
 
Search around, you can find a spring rate chart that will give you an idea. Doesn't matter much, it's trial and error anyway. Coil springs are cheap, cut some and see what you get.
 
Cut 3/4 turn..ended up at 3.25 over factory withy new isolators...stiffness is firmer than uncut for sure. Can feel it while cornering & braking..I don't run sway bars so its a plus. I'm happy with where they ended up.
 
Back
Top