How much to cut off??

[Nova73]

I was wondering if anyone knew any rule of thumb measurements for cutting your coil springs, sorta like if you cut so many inches off the coil it will drop the front about x amount of inches, I have moroso trick springs up front and am looking for a 2 inch drop, if anyone knows around how much i should cut so im not cutting, putting back in and recutting that would be great. thanks

[69Nova]

There is no exact science. The smartest way to do it is going to be cutting some a test fitting it to see how much it lowered it. I say cut 1 full coil at a time. Dont forget the more you cut the coil the rougher the ride will be.

[nancejd]

I thought you were only suppossed to cut 1/4 coil at a time. You can't add it back after all.

[69Nova]

I thought you were only suppossed to cut 1/4 coil at a time. You can't add it back after all.

Depending on how low you want to go that would take forever. I guess you could play it safe and do 1/2 coil at a time.

[Norm Peterson]

I was wondering if anyone knew any rule of thumb measurements for cutting your coil springs, sorta like if you cut so many inches off the coil it will drop the front about x amount of inches, . . .

You can make a crude estimate based on the spacing between adjacent coils (in the loaded condition) and the spring's motion ratio (amount of spring compression relative to the amount of wheel motion). For springs with tangential ends, anyway. Pigtailed or squared springs behave a bit differently as the first coil or portion of a coil is removed.

Really rough example: 2" between adjacent coils with the car sitting only on its wheels, coil spring exactly halfway between the chassis bushings and the balljoint. One coil at the spring will be close to a 2" reduction in its loaded length, which then becomes 4" at the wheel.


Norm

[zbugger]

The 1/4 coil might take a while, and multiple attempts, but it's the safest way to go. The GENERAL rule I've heard is something like 1/2 coil is 1". It's by far not that accurate though. Like I said, it's general. Going 1/4 coil at a time is worth the effort.

[paul67]

Also you might be resricted by how the spring sits , there is 1 way put a block of wood under each side of the car under the lower control arms at the height you want, then get a fire blanket , heat the bottom of each coil up to when the car starts to go down heating the spring for about 4 -5" in length then wrap the coil in the blanket till cold, then repeat, you MUST USE THE BLANKET so as the coil does not cool down to quick also not to be done in a cold draft . I know i will get flack for this but it does work and has been done for years.If its done right theres no problem.

[69Nova]

No problem? Thats seems like it would compromise the springs performance. Maby I'm crazy.

[paul67]

Done it a few times but you must allow the spring to cool slowly that where the mistake made cools to quick and snaps , thats how the springs are made the first time heated coiled cooled slowly. If you took your leaf springs to be rearched they would only heat them up and bend them the left to cool slowly.

[chicane67]

I thought you were only suppossed to cut 1/4 coil at a time. You can't add it back after all.

Yup....... a 1/4 at a time.

[Nova73]

well after unbolting the lower control arms, when i was removing the coils i found that the coils were not fully seated in the control arm pockets, the were about a 1/4 turn out of the seat, so i cut 1/2 a coil to play it safe and reseated the coils in the pockets properly. I got around a 1 1/4 drop, i still have around 1" of air between the tire and fender lip, so im gonna take it apart and cut another half, i would like to see it sit around the same proximity of the rear tire and the lip on quarter and thats about 1/2" cover on the tire sidewall. car should look sweet as hell when im done, ill post some pics. give it that low stance with that beefy look, the car has a 4 3/4" cowl induction hood that really makes it look mean, being low will only add to this combo. Im really in love with the way my car looks with 17's instead of 15's and a lowered stance instead of that 70's hot rod rake with air shocks.