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Cut Coils Today...Couldn't be more pleased with results

Yeah, but it would only soften it an inch or so from the cut. I'm only guessing since I've never tried it. It would change the rate by a fraction, not near as much as taking part of the coil away though.
 
Today I finally got around to cutting my front coils today. I ended up taking off a 1/2 coil. I am very happy, with results. Drove to the alignment shop and it didn't rub at all.
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I'm guessing that the front tires are 225/45's on 17 x 8's. Mostly for comparison to the various tire sizes the car could have originally been fitted with.


"jonward786" said:
I thought others would benefit from seeing how much of a drop 1/2 a coil gives so they could decide how to cut their own.
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You can calculate from the spring's motion ratio and the loaded coil spacing (use the center distance between adjacent turns) to get a pretty good idea where it'll end up. If anything, you'll tend to end up a little high, rather than a little low.


I didn't cut the coils myself because i dont have those kind of tools (yet). I ran down the road to a machine shop / welder and asked him to cut em with a low heat method because i didnt really want to bust out the hacksaw. He goes "why can't i just use a torch?" I replied, "Well ive read heat could damage spring rate, so if you have a cutting wheel or something, could you just use it?" He goes "Whoever told you that is an idiot, you would have to heat these things at 600 degrees for 5 hours to damage them" I just smiled and said "No torch please". So i guess everyone on the internet is wrong according to welder bob, haha :shrug
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I've got to give welder bob at least partial credit here. And not everybody on the 'net flat-out disapproves of using a torch to do this . . .

Partial because if your acetylene kit is "big" enough to get the cut started quickly and keep it going, you absolutely can use a torch to cut springs.

If it's not, you'll end up putting more heat into the spring than necessary.

Yes, there will be a length of the first coil that may get annealed (softened) even on a quick cut. But that's the part that sits directly on the spring perch anyway, meaning that it isn't involved in any flexing. In fact, it might even be a good idea to let the end conform to the contour of the perch by letting it bend a little and stay bent that way.

If you were really worried about heat traveling along the wire, I suppose you could lay the spring down in a pan of water about deep enough to cover half a coil diameter.

Internet wisdom on using/not using a torch to cut springs may be confusing torch cutting with the practice of simply heating (without cutting) springs in order to make them sag. Now that's a much more difficult procedure to control and probably cannot be guaranteed at all.


Norm
 
Just to jump in - I too have used a torch to cut springs. It does only heat up a short piece of the spring and I've never had an issue with it. I use a cut off wheel now but back then, I didn't have one.
 
Our suspension guy at the shop told me when I asked him to cut my front coils, to just heat them up.

He said that one - you don't remove them and two the car will ride better and align easier. he told me to never cut the coil! I have to ask more when I get time, but I am thinking of having him do it while we are slow. He does tons of suspension work.

I think when I get the 65 dumped an inch I will post pics and all the reasons to help.

Mel
 
"guruatbol" said:
Our suspension guy at the shop told me when I asked him to cut my front coils, to just heat them up.

He said that one - you don't remove them and two the car will ride better and align easier. he told me to never cut the coil! I have to ask more when I get time, but I am thinking of having him do it while we are slow. He does tons of suspension work.

I think when I get the 65 dumped an inch I will post pics and all the reasons to help.

Mel
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If by "riding better" he means that the ride quality during easy driving on reasonably good roads does not stiffen up, he's right about that much. Cutting springs does stiffen them slightly. But being more likely to be whacking the bump stops when the driving gets more enthusiastic or the roads get worse generally equals a poorer ride.

With heated and collapsed springs, you'll end up with two front springs that are all but guaranteed NOT to match as far as either free height or loaded height is concerned. It works the stabilizer bar(s) harder just keeping the car close to level as seen from the front or rear (even when just driving in a straight line), and the handling will tend to differ more than it should in right turns vs lefts taken at the same level of "enthusiasm".

If you never drive very hard, you probably wouldn't notice, but if you do drive hard you can't help but see the lack of symmetry as being just as bad as if your new car came through with one spring from the big-block parts bin and the one on the other side from the sixxer stock. The car never would be all it could have been.


If the heating is done carelessly or improperly, you can end up with a spring that either has little notches burned out of it from an oxidizing flame or a brittle region from a reducing/carburizing flame, and these defects WILL be in the region of the spring that is constantly flexing. Think metal fatigue here - either of these situations is a broken spring waiting for a time and place to happen.

Never mind that when you drop the car, you really should be stiffening the springs a little to partly make up for the bump travel that you gave up when you lowered the car.


Norm
 
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