Hi, I just acquired a set of 164 front coils, which I am going to put on my 142. I want to lower the front by 2" (at least). I remember reading somewhere that you cut 1/2 of what you want to lower the car by. So in my case 1" or 1 coil. If anybody can confirm or refute this it would be much appreciated.

Chris,
68 142S

You've got the right idea... if the center of the spring seat in the lower a-arm is 1/2 distance between the lower a-arm inner pivot point and the center of the tire contact patch, then 1 inch cut from the *loaded height* of the spring will result in the car sitting approximately 2" lower. Incidentally, I don't know that the spring seat *is* 1/2 distance to the contact patch, you'd have to measure to confirm that fact. Also notice I've tried to emphasize the term "loaded height"... we're not making the *free height* of the spring 1 inch shorter, we're making the *loaded height* 1 inch shorter.

WRT rate change, according to the manual, stock 140 front springs are nominally 310 lbs/in. If you start with a stock 164 front spring, you're up to about 360 lbs/in, again per the shop manual. If you eliminate one free coil, the spring rate will go up about 14%, to around 410 lbs/in, assuming the stock spring has about 7 free coils. (The 164 manual is a little fuzzy here, but I *think* it says they have 6.83 free coils.)

Keep in mind, the term "free coils" is important when calculating rate changes. If you simply lop off the top or bottom coil and stick the spring in the car, you can throw all this math out the window because those coils aren't "free" to start with. As installed and loaded, the bottom and top half-coil (or so) are typically "coil bound" due to the way the spring is wound. This flattened seating area of the stock spring needs to be duplicated (reshaped) when you cut it, or like I said... this math is all out the window.

Bottom line, you'd be increasing the front spring rate about 30% in the example above... you're going to have to do something at the rear of the car to compensate, or you're going to end up with a LOT of understeer.
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Gary Learned - '71 142E ITB / '73 1800ES / '02 S60 T5

Hi thanks for the input, however (gulp), I started the job by taking 1.5 coils off the top of the spring (and flattened the top coil). When I reinstalled the coils it heightened the overall stance. I was not satisfied, so I took almost another coil off (by now the coils are pretty short). Putting them back in I notice that they are now loose on the unweighted A arms. It did lower the car the amount I wanted, but the ride is pretty soft (should have kept it the way it was). A lesson to those thinking of doing the same.
If you have any suggestions of what I might be able to do to stiffen up the suspension tremendously I would appreciate it.

Vintage Performance Developments can very likely supply you with the springs you want.

Well, I have to ask... did you actually remove these springs from a 164, or were you simply *told* they were 164 springs? 'Cuz if you cut 1.5 coils from these springs and your car ended up with more ride height, then in my opinion, you weren't working with stock 164 front springs to start with. According to the shop manuals, 140 and 160 front springs are very nearly identical. The 160 springs are made from slightly larger wire, so they are stiffer, but only a little. Putting stock 164 springs in the front of a 140 would theoretically raise the car slightly, but unless the old 140 springs were absolutely shot (and the 160 springs were like new), I would be surprised if you would see a big difference in ride height. You're obviously describing something totally different, with the cut springs actually raising the car. Also, 164 springs with 2.5 coils gone will definitely NOT ride softer than stock 140 springs.
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Gary Learned - '71 142E ITB / '73 1800ES / '02 S60 T5

Naw, that can't be quite right. The spring is in the center of the control arm, so if you would get twice the drop of what you cut off *except that* the spring then has fewer coils is stiffer than one with the regular number of coils, and will compress less under the weight of the car.

Make sense?

I bet that 164 springs already have a higher rate than 140 springs, and the more you cut them, the stiffer they get beyond that. You stand a chance of ending up with as much suspension travel as a go-kart.

There are very nice lowering springs available in both linear and progressive rates...