Cutting Springs

[LowStandards]

I'm about to lower the front of my Mazda, but since its a daily I have limited time to get the suspension off etc.

Is there some sort of calculations that can be made so I only have to remove it all once and only make one cut?

Cause the back


No longer matches the front...


Any help?

More pics at
clicky

[Odin]

Seth did some spring maths so he'd be the man if you wanted to work it all out, but I would prefer the easier but perhaps slightly more tedious route of cutting a bit at a time and checking it.

You're wanting to close that gap, yes? What are the springs like (outside diameter, number of coils, etc)? From my experience, the first coil never takes off that much (1" max) and subsequent coils drop around 1.5". This all depends on the spring design, axle loading, and so on though.

[LowStandards]

I have the spring rates, free length, coil diameter etc in the workshop manual. If i was clever i'd of written it down.

I imagine there's some way of figureing it out, like i said i'd rather only pull it apart the once...

[Seth]

Yeah, those numbers would help pus the weight of the car

Firstly though what kind of ends do the springs have and will they fit securely once chopped? Looks like its a Strut arrangement?

[bazzateer]

Cut one coil off and see how it goes. You can always do it again the next weekend/evening. Surely not that much of a hardship?

[Odin]

If that's a strut then I would go straight in with two coils off, and probably end up taking another one off after checking.

[hongkongphooey]

The second time you dismantle it will be at least 3 times quicker than the first so it's not that much hassle.
I tend to always start with a coil and a half though.

[Deleted]

what was rear dropped by ?
going by what i can see of the strut under there i would say 2 complete coils should see it level

[JohnnySomersett]

I always do mine 'in situe' with spring clamps...takes about 15mins a corner. I always take 2 off first then go from there. the 100A had 5 coils out in the end lol, the wagon lost 3

[Odin]

Jul 21, 2008 10:25:37 GMT nightmaresracing said:

what was rear dropped by ?
going by what I can see of the strut under there I would say 2 complete coils should see it level

You can see a strut in that arch? I can't see sh!t on this curse word monitor, just a big shadow.

Edit: yo, Johnny - for a five coil drop your springs must have been pretty beefy originally, yes? With a three coil drop I've only got three left.....

[JohnnySomersett]

yeh, the spings were massive (as was the ride hieght)!! 5 coils out left it sat on the struts tho lol..that's why it now rocks coilovers

[jettadeluxe]

Here's the theory I use;

Remove car wheel, load the suspension by placing a axxle stand underneath the lower suspension arm and dropping the jack so that the spring is at 'normal' compressed height.

Measure the distance between two coils, top of coil to top of coil. EG, if the distance is 2", then the drop by cutting out a full coil turn would be 2". If your springs are flat-topped, then you disregard the first 'flat' turn, or allow the small amount of the diameter of the material the spring is made from.

You can also 'roughly' factor in the reduced spring length to allow for the increased spring weight per coil. i.e., if there are normally 6 coil turns per coil, and you reduce it to 5, the each coil will compress further with the reduced amount of coils. Divide the original number of coils by the proposed remaining number of coils to give you a factor number, in this case 6 divided by 5 = 1.2. Then times the original measurement between coils by the factor number.

2" times 1.2 means that if you had six coils and take one out to make 5, the actual drop will be around 2.4".

This is by no means scientifically correct, but should be accurate enough to put you in the right direction.

[LowStandards]

The rear has been dropped on 2inch blocks. The front springs are of a fair length, I don't think i'll be able to do it in situe as the turret 'hugs' the spring at the top for a good 8 or 9 inches and I cant get a compressor in there.


The springs are straight cut and locate at the bottom in the strut cup and at the top in one of them formed rubber affairs that spins so I can cut anywhere around the spring...