cutting my springs?

Struts, spring, anti-rollbars, braces and the like.

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TurboLegacy
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cutting my springs?

Post by TurboLegacy »

will it kill the way my car rides if i cut them an inch and a half?
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
THAWA
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Post by THAWA »

yes, and mke it much more unsafer
Rio Red 90 Legacy LS AWD 174k
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kastrix
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Post by kastrix »

We call that Ghetto Hydrolics around here. Dont do it please!!!!
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vrg3
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Post by vrg3 »

Cutting a spring will increase its stiffness. The spring rate of a uniformly wound spring is inversely proportional to the length of the spring, so cutting, say, an inch and a half off a 16-inch spring with a spring rate of 134 ft-lbs will yield a 14.5-inch spring with a spring rate of around 148 ft-lbs.

It's a little more complicated with your car's springs, though. These springs aren't uniformly wound. They're somewhat progressive, so that they can soak up small bumps easily while not collapsing under heavier shock. That improves ride quality, but makes the springs somewhat more complicated. It may be hard to predict exactly how the spring rate will be affected by cutting the spring, and at the same time you are likely to lose the little bit of progressiveness that helps maintain ride quality and control simultaneously.

There's a bigger issue with cutting your car's springs -- it presents a safety problem. The stock springs are shaped in such a way as to provide a nearly ciomplete circle at the interface between the spring and each of its seats. That is, the first and last turns of the spring are nearly flat, not angled. This allows the entire spring seat to support the weight of the spring (and in turn much of the weight of the car). If you cut the spring, the spring will end at a sharp angle, concentrating all the stress on one small portion of the seat. It's not hard to imagine the seat eventually giving way at that point, allowing the spring to fly loose. If you're really lucky, it'll happen while the car is parked and nobody will get hurt. If you're really unlucky, it'll happen while you're working on the car and the flying spring will take off your head (those springs have an insane amount of potential energy in them). Or maybe the worst case would be if it popped off while you were driving, causing you to lose control of the car and cause a multi-car pileup, killing multiple people.

So, I guess my long-winded answer to your question is just to agree with THAWA and kastrix: Yes, it'll likely compromise both ride quality and safety.
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evolutionmovement
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Post by evolutionmovement »

Plus it looks stupid driving down the street and everyone but ghetto people will laugh at you.

Steve
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Post by vrg3 »

How can you tell the difference between proper lowering springs and cut spring just by glancing at a car coming down the street?
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evolutionmovement
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Post by evolutionmovement »

Serious rediculous bounce (probably combined with stock worn struts) and usually uneven ride height. Its part an assumption, but I would guess people buying actual springs would upgrade the struts too.

Steve
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
kastrix
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Post by kastrix »

Typically the front end bouncing off a stopliight is a good clue... But like steve said that probably comes with worn stock struts/shocks.
@The Beast@
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A good car is like a good woman...
She will turn on when you want her to and she will always give you the ride of your life.
206er
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Post by 206er »

I think it depends on what you want out of the car. if you drive it hard and have crappy roads then don't do it. If you are after looks and intent on doing it, cut one coil first and then 1/2 coil if you want more. don't use a torch.
cutting springs gets a worse rap than it deserves. a lot of cars can benefit from lowering the CoG a little, trucks especially. lowering springs are much better of course, but if you are on a budget then why not try it.
Additionally, many mac strut cars should not be lowered to the point where the control arms go past flat and angle up \.__./ This makes the roll center go below the CoG. this is bad because it makes it much easier for body roll to happen. basically the CoG has more leverage on the roll center.
so, lower at your own risk.
1994 Touring Wagon: ruby mica, 5mt swapped
LaureltheQueen
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Post by LaureltheQueen »

DONT! I know you tend to do ghetto things to your car, but stop listening to your friends and listen to people who know better. If there's someone giving you a reason not to do something, listen to it.
Laurel Tuning Stage 15
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sullione
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Post by sullione »

Just get you a set of lowering springs. You'll be glad you did. If you don't have all the cash now, just save a few dollors here and there and (everyone can do this if they watch their spending) in no time you'll have enough. :D
James
1991 Legacy LSi sold!!!
2003 Infiniti G35
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