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Cutting Rear springs...to level the car...(not a newb at cutting) but...

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Old 11-23-2009, 07:59 PM
  #11  
Norm Peterson
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The it must be due to production tolerances or variations in spring free length and rate.

I just stepped outside and measured less than about 1/4" difference in the front and rear fender heights on my '08 GT, looking straight-on in side view (and the front was the larger measurement!). Front tires might stand a tiny bit taller than the rears due to them being inflated 3 or 4 psi higher, so I guess my "gaps" are pretty close to even.


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Old 11-24-2009, 10:39 AM
  #12  
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I rode around for a year on cut rear springs. I didn't like the look of the rear fender/wheel gap so I purchased a set of take-offs on ebay and removed exactly one coil from the top of the rear springs. This leveled out my car nicely but I was not happy with the "feel". It removed most of the wheel hop, but didn't feel great in the corners. After a year or so I put on steeda ultralites and d-specs front and rear, which I like much better. What I found when I swapped out all the springs was that the front of my car was lower than most to start with and the steeda springs only netted my a 1/4" drop from where I started in the front. The rear dropped about 1.25" from stock or about 1/4" more than with the cut rear springs. So it ended up "looking" just about the same, but feels much better when driving. This is probably due more to the d-specs than the steeda springs, but either way I'm happy. If I was to do it again - I'd do springs and shocks together, but if $$$ are an issue, the I'd get the springs I want and just replace the rears (provided the drop is mild) until new dampers are affordable, then swap in the front springs and dampers together. The way the front springs are clocked, you have to remove entire coils if you are cutting - so I don't recommend messing with the front springs at all.
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Old 11-24-2009, 11:04 AM
  #13  
Ken04
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Originally Posted by Kona6Stang10
the main issue here is the amount of wheel gap relative to the front wheel gap.....I can fit my entire fist and one finger in the rear gap of the wheel well ....whereas in the front I can fit about 3 fingers.

It's a pet peeve of mine....if any of you have seen my last car I hate wheel gap

My last car had 1 finger gap in the rear and I couldn't even manage to squeeze my little finger into the front...
Rolled fenders of course

I'll post pics!
the S197's do sit *** high, so cut away. Guys have been cutting springs since springs were invented, so cut yours. Geez what's the worst that could happen ? Some people are way too paranoid. Just pull them out and hack away, if you hate it you can buy stock springs for $20. I'm sure you know not to use a torch and heat the temper away, but other than that, post pictures and impressions when you're done.
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Old 11-24-2009, 03:29 PM
  #14  
socalwrench
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Cutting the springs is not a big deal, but there some guidelines.

1) NEVER use a torch or use any kind of heat to cut the metal- this changes the characteristics of the metal and it will eventually fail (sag or break). Use a cut-off wheel or grinder with a cutting disc, and keep it cool. If it begins to turn orange, stop and resume soon after.

2) Be sure that the spring will fit back into (or onto) the perch after it's cut. Some springs have pigtail type ends that cannot be removed.

3) Measure before cutting. This goes without saying, but I've talked to a few guys that just hack away and end up with poor results. Remember, when you are measuring a spring there's a huge difference between the installed height and the free height. As the first name implies, the installed height is with the weight of the car (per corner) that actually compresses the spring.

4) Cutting a spring will stiff it (raising the spring rate). This is because you are removing the coils which are responsible for bending. The less coils there are, the higher the rate goes. This rules applies to active coils, not the flat or end ones. You must keep this in consideration since the installed height of the spring will change- as it will not compress as much from the weight of the car (again, per corner).

5) Do your math before making the cuts. Figure out how much lower you want the car. Determine how much the spring compresses due to weight, and use that weight to determine how much your newly cut spring will compress (remember, it will be less). This can be tricky since you're going to be cutting the spring at it's free height. This is where most people make a mistake, since cutting a spring at it's free height will not be where it stays when it's installed.

Best of luck!

Two other things to note when altering springs: the spring rate increases when reducing the outer diameter, or increasing the wire diameter.
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Old 11-24-2009, 08:06 PM
  #15  
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Not to beat a dead horse with my suggestion but the clamps will probably help you better determine exactly where to make the cut if you clamped the springs exactly where you want the height. Then you can measure the difference.
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Old 11-25-2009, 09:48 AM
  #16  
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While clamping, or marking, the location would get you close- it still doesn't take into account that the spring will become stiffer. Therefore, it will compress less than the original, and the car will not sit at the marked location.

Anyway, I think everything has been said about cutting springs.
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Old 11-26-2009, 08:51 AM
  #17  
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I cut my springs in the new edge with no problem, just used a cutoff wheel and took my time to make sure everything was measured correctly. But what I did was bought a complete set of take off first, that way if I did mess something up I wasnt without the veh until I could get new springs.
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Old 11-27-2009, 07:48 AM
  #18  
Norm Peterson
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Originally Posted by Ken04
Guys have been cutting springs since springs were invented, so cut yours. Geez what's the worst that could happen ? Some people are way too paranoid. Just pull them out and hack away,
Not paranoid, just careful with a great deal of respect for the rest of what goes into making a good spring. Some of it is from an engineering point of view and some is from direct experience.

(1) You cut too short and a spring falls out on your test drive (you do take careful test drives after performing chassis mods ???)

(2) The end configuration after cutting does not fit the vehicle's spring seats. Think pigtail-end springs and springs that need to be cut in specific increments (like in full coils). Ride height more than likely still won't be 'right', corner weights will be off, the spring's axis will try to bow out of straight because the cut end doesn't want to sit flat any more (this increases the likelihood that it might pop out).

(3) You cut or otherwise hot-work the spring using poor technique, add even more carbon to the steel composition, and it fractures. If you'd ever had to drive a car knowing that it had a broken spring and the situations that could easily cause the pieces to fall off the car . . . never mind the details regarding how I might know this.


You asked . . .


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Last edited by Norm Peterson; 11-27-2009 at 07:50 AM.
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Old 11-28-2009, 10:42 AM
  #19  
Rubrignitz
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I just purchased a set of Steeda ultralite springs from Sam to use while I figure out how to get my Steeda comp springs front ride height level with the rear. As it sits now, the front is 1/2'' higher than the rear! Not sure if it's my combination of mods but it seems even more offset now with the X5 balljoints and new control arms.

I was seriously considering lopping off ~1/4 of a coil on the steeda comp fronts which should be just enough to level the ride height. Being a tangential-end spring it wouldn't be difficult to do.

I love the springs but hate the higher front end. I've just lived with it since the springs are so nice but have finally decided to either swap springs or fix the steeda comps. If I like the ultralites I'll keep them, if not I'll be trimming these comps...
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Old 10-21-2012, 05:29 PM
  #20  
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Default How to Measure Where to Cut?

I wanted to revive this thread because I am going to cut my springs on my 2005 convertible to lower the rear by 1". Folks who have done this say to remove one full coil.

Two questions:

1) Exactly how do I measure one full coil? Just cut the underneath where the end is?

2) How do I make sure the newly cut end sits right, and not at an angle? Some have suggested turning the spring upside down because this put the newly cut end in a more stable position.

Thanks,

BL
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