Cutting stock springs 2g

[Thomas91169]

So i have a set of stock springs i found in the attic. Right now Im on Koni Yellows with GSX springs and the car is 4x4 status. Car is my DD and right now i really have no intention of buying $100+ springs for it when i have a set i can modify for free. I have a set of Skunk2 ebay coilovers that came with the car but they lack the ability to sit on any shock perch other than the stockers (tried GR2's and these Yellows and the spacer for the coil hat always never sits right and slips past once weight is applied), so if im gonna spend money on anything, ill have a machine shop build me proper spacers for them to work properly.

Thinking on cutting the spare set i have and throwing them on, however all i can find is the back and forth bickering about how its a sin to cut springs, rice, yadda yadda.

All im looking for is to take maybe 1/2"-3/4" out of the ride height. Does anyone know if that equals roughly half a coil? 3/4 of a coil? etc? Ive taken half a coil out of ford C-springs on my GT to give it an extra bit of rear drop to level it. I believe its perfectly OK to cut up to a full coil off depending on the spring rate and not affect it as much as people think, i think more damage is done due to heating up the spring itself when cutting it.

 

[LiquidX]

Do NOT cut your springs! It is very unsafe. The springs are wound to support x weight and have x spring rate. Cutting will alter both making the car less stable. Leave them uncut and buy the proper springs.

I'd stay away com an eBay coilover kit as well.

 

[kimcheefists]

For as long as you've been on this forum, I would think you'd know that cutting springs is a very bad idea...

 

[cookmeup272]

i was gonna say the same exact thing

 

[914g63gsx]

i cut my springs befor on my gsx did not have a problem at all untill the front springs lost their spring rate like they were wooped bad. but this was after about 4 months, its not worth cutting your springs at all unless you just want to see what ## car will look like lowered for like a week. i dont see how its dangerous ### they sat the same as lowering springs. now with the ebay coil overs i have them on the front of my car untill i can afford a good set of springs or coil overs. their a nice stiff ass ride in the front with a good set of struts, the ebay coil overs arent that bad. if i were you i would just wait till u can afford a nice set its not worth the work of swaping all that out 2 times when u dont have to.

 

[GsXdSmKingGsX]

Its a terrible idea. Ive seen too many chopped stock spring cars go to hell. It cannot support the weight because there isnt enough of the coil left.

 

[LiquidX]

Lowering springs have the proper spring rate and are coiled tighter which makes them a smaller profile and still have proper handling characteristics.

 

[kimcheefists]

Lowering springs are obviously stiffer than OE springs. When you cut OE springs to lower your car, the spring rate (stiffness) will be same but will be shorter and will have a higher chance of bottoming out.

 

[yukiz]

as others suggested, dont cut your spring...bad idea.... if you want i have H&R Springs for sale... let me know... only 2000 miles on them before i sold my old N/T.... there are picture on my gallery if if you wanted to see.......

 

[RamenPride]

Lowering springs are obviously stiffer than OE springs. When you cut OE springs to lower your car, the spring rate (stiffness) will be same but will be shorter and will have a higher chance of bottoming out.

cutting a spring will increase the spring rate (ie make it stiffer). I could never get the minimal drop I wanted with a decent ride. After trying a bunch of setups, I cut my stock springs. It was a lot of trial and error to make sure it was even, but I'm happy with the results. I'm using them with Tokico Illumina's, and the cut springs haven't caused me to lose control and die. If you were to use a spring with an increased rate and stock shocks, then you would have crappy and bouncy ride.

 

[BLINKY619]

ok now if you have a spare set like you said... then i would.... and then install them, now if you dont like it. then put your other ones back on...

 

[BoostedBeater]

Sorry but your wrong. The spring rate on progressive springs lessons as they get closer to the center... I have no idea how you could possibly even think of some reasonable logic behind your theory that cutting the springs will increase the rate.

And if your theory is correct then why dont you have a bouncy ride due to the increased spring rate with your stock struts?

 

[RamenPride]

Sorry but your wrong. The spring rate on progressive springs lessons as they get closer to the center... I have no idea how you could possibly even think of some reasonable logic behind your theory that cutting the springs will increase the rate.

And if your theory is correct then why dont you have a bouncy ride due to the increased spring rate with your stock struts?

I'm assuming this is directed at me? The stock springs as far as I know are not progressive, and I never said they were. Simple reasoning would tell you that shortening any spring will increase its rate. It's not "my" theory, it's fact. If you use a spring rate calculator and change nothing but the number of active coils, you'll see that the rate increases as you decrease the number of coils.

Coil Spring Rate Calculations by Wallace Racing

My ride is not bouncy because I'm NOT using stock shocks as clearly stated in my post.

 

[master jared]

do not do that it will kill the ride of the car and it will be rice as hell

 

[Achelea]

cutting a spring will increase the spring rate (ie make it stiffer)

Let me ask a question. . HOW does removing material make them stiffer?

You are aware of metal working techniques. Right?

Like annealing, tempering, and so forth? They manufacture springs a specific way, and use specific heat treating methods to get the desired effect.

Here's a nice quote that states it perfectly.

Damage to springs, such as using oxy-acetylene to cut the end off a car suspension spring to lower a vehicle's ride height, can destroy the tempering in localised areas of the spring.

http://www.youtube.com/watch?v=Ix4-UUelDc4

Cutting suspension to lower a car or increase performance is like chopping off the end of a Katana with a blow torch because you wanted a short ninja sword. You would ruin it! (By the way, Japanese Katanas are made by making the back softer than the blade, so it has the hardened edge to cut with, but the flexible back to allow it to be flexible enough not to shatter.)

 

[RamenPride]

I used a hacksaw to cut them. I am well aware that using a torch to cut off the end or heating the spring to compress the coils will alter the characteristics of the spring.

 

[knochgoon24]

...Simple reasoning would tell you that shortening any spring will increase its rate. It's not "my" theory, it's fact. If you use a spring rate calculator and change nothing but the number of active coils, you'll see that the rate increases as you decrease the number of coils.

You fail to remember that you're shortening the uncompressed length by cutting off coils. Make the correction there and you'll notice that you are no longer changing the spring rate.

Cut the spring too much and you'll soon be bouncing off the bump stops.

 

[19Eclipse90]

The math involved in analyzing springs is pretty straight-forward. The spring rate (or constant) depends on the number of active coils in the spring. The full equation for the spring constant is such that it is divided by the number of active coils -- meaning that decreasing the number of active coils will raise the spring rate.

Assume a constant load is applied to a spring in each case. First the original spring will have a constant k and deflect a distance x. The second, modified spring will have a constant j and deflect a distance y. While k < j and x > y, it would appear to make the spring stiffer. In my opinion saying the spring is stiffer is very misleading. You're comparing two different springs, apples and oranges if you'd like. knochgoon24 touched on what would need accounting for, so I won't delve into that.

In addition, it is important to take the configurations of the end coils on the springs into consideration; I believe that our cars' springs have closed (squared) and ground end coils. Depending on how much you take off, you may actually increase the number of active coils, decreasing the spring rate and - following the train of thought in this thread - softening the spring.

Aside from all this, here is a nice article about lowering your car for performance purposes for those who are interested: The Ultimate Handling Guide Part V: The One Unforgivable Sin, Overlowering Your Car