I say don’t cut them because when you buy a lowering spring it lowers the car while also making up for the lower stance through added rigidity. You cut the springs and you’ve lowered the car, but the springs aren’t going to magically firm up. You’ll end up with a suspension with a lot more play than should be aloud. Also, bouncy bouncy!
cutting coils off stock springs?
- Thread starter fastsnake99
- Start date
Drop the IRS down to remove the rear springs. Makes it real easy.
learned this from physics class in regards to springs. perhaps there are some experts here who can chime in.
K is a spring constant referring to the stiffness of the spring.
K is inversely proportional to the # of turns/coils for the spring.
so if u reduce the # of coils, ur effectively increasing the stiffness.
i know this applies to linear springs but not sure about progressive. this is assuming the wound up diameter of the spring is constant.
the great thing about buying aftermarket springs is that, although they're cut to get to the desired ride height, the spring rate is predetermined. cutting a stock spring rated at 600lbs will increase the stiffness to an undetermined value.
K is a spring constant referring to the stiffness of the spring.
K is inversely proportional to the # of turns/coils for the spring.
so if u reduce the # of coils, ur effectively increasing the stiffness.
i know this applies to linear springs but not sure about progressive. this is assuming the wound up diameter of the spring is constant.
the great thing about buying aftermarket springs is that, although they're cut to get to the desired ride height, the spring rate is predetermined. cutting a stock spring rated at 600lbs will increase the stiffness to an undetermined value.
I havent tried just the springs but I think dropping the IRS for them would be overkill. I currently have my whole rear ripped apart, half shafts out, IRS down, LCA's off. And If I were to just do the springs. I would support LCA's and then remove lower shock bolt, sway bar end links and lower knuckle bolts then lower the control arm.
Man where did you go to school? haha.
Cutting the springs down won't change the spring rates at all, however, when lowering a car you want the new coils to be stiffer, hence aftermarket springs are stiffer so your car doesn't bounce like stock and bottom out/have fender clearance issues.
(With progressive springs, It depends on which end of the spring you cut from).
Cutting springs is the WRONG way to lower your car. Springs are cheap. Do it right or don't do it at all. $250 is CHEAP. I spent $1600 on the coilovers on my WRX, but they were worth every cent.
On DSM's cut springs is common.... blown struts are a common result due to loads too far outside design specs of strut. They also had issues with breaking axels due to camber conditions over -3 degrees. etc.
That is the worst advice I've ever heard!!!! If you drop the IRS for a spring install you're wasting your time.
Jack up the rear control arm until you've loaded the suspension in that area to the max
Install an internal spring compressor
Unbolt everything from the control arm (the shock and whatnot)
Release the pressure on the jack
The spring should fall out
Compress the new spring
put the new spring in, jack the suspension back up
reattach the shock and whatnot
remove the internal spring compressor,
Remove the jack
you're finished with one side of the IRS.
Stang2WRX
have u taken a physics or dynamics course and know anything about hooke's law?
where did u go to school at? :shrug:
follow the link for some useful reading.
spring tech tutorial
have u taken a physics or dynamics course and know anything about hooke's law?
where did u go to school at? :shrug:
follow the link for some useful reading.
spring tech tutorial
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DO NOT DROP THE IRS!!!
with car on stands and wheels removed...Place a jack under the control arm and jack it a little to compress the spring. This will allow you to undo the lower shock bolt, also remove the lower bolt that holds your hub and brake assembly so it can swing away from the arm pivoting on the top bolt (now the control atm is not attached only where it pivits at the irs frame), dont forget to undo the brake line where it's bolted to the arm. By undoing these you will be have more movement in the control arm when you are removing/installing springs. With the jack still keeping the spring compressed, insert the compressor...you wont have to turn it as much if the jack has it pre compressed and you may have to adjust jack height to get the compressor in place. Compress the spring as much as possible before lowering the jack, a second set of hands will help by pushing the control arm down where you unbolted the lower hub bolt so you can pull the compressed spring. If you are installing a new spring you will have to use the compressor to get it in, If you are cutting a coil off the OE's you may or may not need the compressor to get it back in.
TIPS: Spray WD40 on the threads of the compressor. Get a buddy to help you! Can be done alone, but it is much better to have an xtra set of hands.
OK...I hope this will be accurate enough for you, I'm not the master but this works for me, takes roughly 1-2hrs for back with 2 people. This is strictly from memory too!
with car on stands and wheels removed...Place a jack under the control arm and jack it a little to compress the spring. This will allow you to undo the lower shock bolt, also remove the lower bolt that holds your hub and brake assembly so it can swing away from the arm pivoting on the top bolt (now the control atm is not attached only where it pivits at the irs frame), dont forget to undo the brake line where it's bolted to the arm. By undoing these you will be have more movement in the control arm when you are removing/installing springs. With the jack still keeping the spring compressed, insert the compressor...you wont have to turn it as much if the jack has it pre compressed and you may have to adjust jack height to get the compressor in place. Compress the spring as much as possible before lowering the jack, a second set of hands will help by pushing the control arm down where you unbolted the lower hub bolt so you can pull the compressed spring. If you are installing a new spring you will have to use the compressor to get it in, If you are cutting a coil off the OE's you may or may not need the compressor to get it back in.
TIPS: Spray WD40 on the threads of the compressor. Get a buddy to help you! Can be done alone, but it is much better to have an xtra set of hands.
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Sorry Brad!!
Damn!! I didnt see Brads instructions before posting....They're simple too!
Damn!! I didnt see Brads instructions before posting....They're simple too!
Far from be "the worst advice". Many people have trouble with various spring compressors on these cars. Dropping the IRS was a snap, and my spring install went very quick. I had never done springs before, either.
I guess the jury is out on whether cutting is the "right" thing to do or not. The "why spend $30K on a car then do things the cheap way" is a two sided argument. I HAVE to do things the cheap way in order to be able to afford to modify my $30K car! A lot of the parts I have bought have been used. I have less than $1100 in performance mods so far, and it is running just as well as if I had spent the $16-1700 for them new. I even bought a blower case and ported it myself (FWIW I am a machinist by trade) but have yet to install it.
I cut the coils on my '85 GT back in the day and loved the look and the ride. Rode great for the 4 years I owned it with no suspension troubles at all.
My next question is to those who have cut: did you cut off the top or bottom of the springs? (I haven't even looked at the '03 springs, so forgive me if this is a dumb question.)
Thanks, Jay
I cut the coils on my '85 GT back in the day and loved the look and the ride. Rode great for the 4 years I owned it with no suspension troubles at all.
My next question is to those who have cut: did you cut off the top or bottom of the springs? (I haven't even looked at the '03 springs, so forgive me if this is a dumb question.)
Thanks, Jay
Correct! Here's an easier way to look at it. Pretend a spring has a rate of 500 lbs/inch and has 10 coils. If you put 500 lbs of weight on it, the whole spring collapses 1 inch and each coil collapses 1/10th of an inch (10 coils). If you cut one coil off and put 500 lbs weight on it, the spring will now only collapse 9/10th of an inch (each coil still collapses 1/10th of an inch). It now takes OVER 500 lbs to collapse the spring 1 inch, so the effective spring rate has increased but the stiffness of the spring wire has not (it still collapese 1/10th of an in per coil).
What does everyone think lowering springs are? They are shorter spring (less coils) with a higher effective spring rate. Sound familar?
Either way, I say go with Coilovers!!
No one still has any proof that cutting stock springs is bad.
I have thought about cutting mine, but I am not 100% sure that I am going to.
And why is it that springs for our cars are almost $300? My springs for my GT were about $140. Any real reason why Cobra's are more? Or am I wrong and they are not that much??
I have thought about cutting mine, but I am not 100% sure that I am going to.
And why is it that springs for our cars are almost $300? My springs for my GT were about $140. Any real reason why Cobra's are more? Or am I wrong and they are not that much??
Your car looks really low.
Did you cut them off the top of the spring? How is the ride?
Did you cut them off the top of the spring? How is the ride?
Thanks.
Guess I'll have to decide if I am going to do it or not. I want my car to be a little higher than yours though. So maybe I'll go with 1/2 a coil. I'm already scraping though, so I may not do it.
Guess I'll have to decide if I am going to do it or not. I want my car to be a little higher than yours though. So maybe I'll go with 1/2 a coil. I'm already scraping though, so I may not do it.
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