Cutting spring coil

[kmack]

What's the consensus on cutting a coil or two off the strut springs? I'm looking to lower the car some and add a little negative camber also.

I have a set of performance springs that work pretty good on the track, but I can't get any more camber adjustment. (I need to get a little more for running high-speed events). I realize cutting the spring will lower the car some, not a bad thing, though. How will this affect the spring rate? Will it increase it some or at all?

At this point, I don't have the budget for coil-overs, and standard camber plates are designed to be used with coil-overs. I know MSA has a set of camber plates to be used with stock struts, but I'm afraid that these add to the overall strut height some and won't give me the added negative camber I'm looking for.

FWIW, I already have about 1-1/2* of negative camber. I'm looking for up to -3*.

Any thoughts? Good or bad? I'm just in the idea stage right now.

[240znz]

I lowered my old Datsun 1200 coupe by installing Hillman Avenger rear springs in the front after gas axing 2.5 coils off.

The result was great except for the fear of the coil jumping out off the tower base when I got the car in the air over a hump. You MUST to get the coil under tension or it could cause a very nasty crash.

Yes it handles great but it was a major worry. Face it, you WILL dirve this car to the limit on occasion, so why not do it right and negate the possible risks. Save you money until you have enough for coilovers.

Not too sure about the camber change as you have so much already. You could slot the tower holes or I heard of the struts being bent to get the extra. Where are you planning on using it

James

[PrOxLaMuS©]

Cutting springs are dangerous and can cause your car to loose control easily.

Just buy some shorter springs or coilovers from MSA.

[hls30.com]

I have cut the coils off before, and it works OK. Remove the spring, cut one coil off at the time-(use a cutoff wheel on a diegrinder-or you will be at it a long time and go through many blades) and check your ride height before cutting more. Make sure that you cut the same number of coils off each spring, adnd that you get the cut end butted up right in the perch. A little goes a long way. If I remember correctly, I had Nissan competition springs in the rear, and cut 2 coils off the front to balance the car.

You will be happier with the results if you get a new matched set, but cutting them does work in a pinch! If you are cutting all 4 the spring rate ratio(F to) will remain close as long aas you cut the same number of coils from each spring.

Will

[gundee]

Years ago before the coilovers were widely available, most of us that autocrossed our Z cars cut our springs. Just take it easy and don't cut too much and bottom out the shock.

Some of the guys used front lower control arms from I believe a 710 sedan. They were longer and gave more neg. camber.

They would press out the 710 bushings and press in the 240Z bushings and install. Worked good. There still may be some of old Z's running around with control arms from other models.

[2ManyZs]

Ken, since I know what you have on the car since you bought it from me, I vote against cutting the coils for a couple reasons(at least for now).

1. You have the adjustable bushings that with the "cheap" camber adjustment from MSA should allow you to have in the neighborhood of -2.5 or so camber.

2. If I remember right, the "cheap" camber adjustment plates that MSA have are the same ones that I had on the old ITS 280 that I got from GC. They are a top hat with long studs that protrude through a thick piece of urethane that acts as your top insulator. You can shave off a little of the urethane "top hat" for more lowering, without sacrificing suspension travel. The urethane "top hat" is slotted for a fairly good camber adjustment, which in truth, I never really needed on the rear of the 280 because if offered more negative camber than the tires I was using wanted, and I ended up getting the negative camkber by adjusting the offset control arm bushings.

3. If this doesn't lower your car enough, then you can still cut the spring, yet have to cut less off the spring and not compromise the suspension travel to get the desired ride height.

4. You may find that you won't need more than 2.5 or so negative camber with a lot of today's radials. I know that many of the racers I used to race with aren't running near as much negative camber with the race tires as they did in the past.

This is the camber kit you're talking about right?

http://www.zcarparts.com/store/merchant.mvc?Screen=CTGY&Category_Code=PSDC08

[gundee]

That is a real good point about the modern radial tires. With that flat tread I don't imagine they like much camber like we used to run.

[260DET]

If the car is going to be lowered significantly then consider relocating the inner pivot in the crossmember up and out.

[kmack]

Originally posted by greyghost

Some of the guys used front lower control arms from I believe a 710 sedan. They were longer and gave more neg. camber.

greyghost,

Interesting idea here. Although I haven't seen many 710's around the junkyards lately. Any idea how much longer the control arms were in relation to Z control arms? Were the 710 control arms used on any other models?

[kmack]

2Many,

I don't want to cut the coils if I don't have to. I'm just looking for pros and cons for this option.

1. Yes I already have adjustable bushings in the control arms, but you may remember that the initial reason I got them was to overcome the too much positive camber on the left front suspension. I have since slotted the strut tower on the left front to help make the bushings more effective for camber adjustment.

2. The MSA camber plates seem to be my best bet, but as always, they cost more money than I have. Cutting the springs effectively costs me nothing more than my time. It's the side effects that I'm trying to determine right now and if I want to deal with them.

3. Either way I want to lower the car some. Any other options on doing this other than:

a) relocating/sectioning the strut tubes

buying lowering springs (already have the money issue)

c) buying larger rims to help fill in the space (again money issue)

4. If I could at least get to -2.5* of camber that would be great! But like I said, with bushings, and a slotted tower, I can only get -1* out of the left front. The right front will go farther, but there's no point if the left can't follow.

I'd like to pursue greyghost's idea about the 710 control arms, if anybody has any more info. My other option (that I honestly haven't looked at much) is to lengthen my left control arm. I have already lengthened the left T/C rod to get my caster where it needs to be. That has worked out good so far.

Or I could relocate the control arm holes in the cross member, but by how much? What dimension of movement of the holes gives what change of camber in degrees?

[gramercyjam]

Cutting springs is easy. You don't even have to take them off the car. Jack 'er up, cut the spring in 2 (maybe 3) places.

Cutting does increase spring rate, but not by a whole lot. Spring rate is proportional to the number of coils in the spring. Take out 1/10 of the coils, springs will get 1/10 stiffer.

After cutting springs, they won't fit right in the spring seats, but no biggie.

FWIW, I tried various cut springs, the results were never what I was hoping for. Went to coil-overs pretty quickly after that and got the desired results.

You have seen how much my car has been lowered. I still don't have a ton of neg. camber in the front. Probably about -1. I had to install camber plates in the rear to remove excessive negative camber and put it back to about -2 so I wouldn't need a new set of tires daily.

-2.5 is a lot. Better get a tire sponsor.

Bigger rims to fill up the wheel well is a cosmetic issue unrelated to increased performance. Bigger rims will make you slower unless you offset the increase in rotating mass (inertia) with performance gains elsewhere.

IMO, there is no "cheap" route that will achieve your goals in a satisfactory manner.

[Zrush]

What's the difference between lowering springs and just cutting the stock springs? (Other than....the lowering springs you have to go out and buy and the stock springs are already yours). Are lowering springs stronger/stiffer. Very interesting thread IMO

Vicky