Legalities of spring "Modification"

[OSM Garage]

How legal is this?

Wondering if removing a few of the roundy bits to lower the height of the spring. Assuming that the spring settles and looks factory, would it be ok?

If not, who in auckland can re shape the spring?

[mikuni]

This could probably just have gone in the wof and cert questions thread.

Cutting off the coils on that end will do almost nothing. I've done it before, so have others that I've known, even some I've warned. Cut them off the other side if you must cut at all.

It will make the springs illegal. They sit flat top and bottom and cutting anything off them will change this. To make them legal you will need to get them heated to bring the ends back as they are currently and then get the whole thing retempered in an oven/kiln type device. This will then take off all the powdercoat too, so you will have painted springs. Almost makes it worth while starting with a standard set of springs and just selling these?

[l1ttle_d3vil]

Short answer: it isn't legal. Cutting springs in any way shape or form is illegal full stop.

Just because some WOF officers don't notice "one or two coils" missing doesn't make it legal to chop a coil off.

[OSM Garage]

To make them legal you will need to get them heated to bring the ends back as they are currently

Anyone know who can perform this in Auckland?

[shizzl]

its not illegal as long as the spring is seated correctly and remains captive..

i wouldnt recommend it, take them to archers auto springs to get compressed..

[OSM Garage]

its not illegal as long as the spring is seated correctly and remains captive..

i wouldnt recommend it, take them to archers auto springs to get compressed..

Looking back at past post's it seems that compressing springs has a undesirable outcome. (Too springy)

Trying to avoid compressing if I can. And working with what I got.

[mikuni]

Short answer: it isn't legal. Cutting springs in any way shape or form is illegal full stop.

Just because some WOF officers don't notice "one or two coils" missing doesn't make it legal to chop a coil off.

It may be a short answer, but its a wrong one.

Cutting springs can be made legal and Kevinator is going about things the right way in my opinion.

Snells springs can do the work for you. I think steeliegears can too but unsure there. I use springtown down here to do all of this type of thing and they do a good job.

You are also on the right track with compressed springs. It retains the same spring rate but resets them to a lower height. They will be soft and the car will likely hit its bumpstops etc. The only good thing is that sometimes they stay captive and this is why they are technically "legal" but any certifier will tell you that they are just crap.

I guess the only other question to ask here is whether its worth going to aftermarket springs from a decent manufacturer or perhaps customs? The price will be similar to getting yours reset after you cut them but the advantage to cutting them is that they will be the height that you want. I suspect customs would take a bit to get setup right.

And don't forget you'll probably need shortened shocks to keep it all captive after you cut them, so factor that into the cost.

[Bling]

So long answer... how do you run cut springs legally? Are you talking cert or what? Since modifying springs in any way makes them illegal as is. Cutting or compressing.

That's how I always read the rules anyway, so keen to hear how its legal / a good idea to bother cutting springs. I would always go after market / custom springs over messing around with cut springs. Each to their own demise though.

[isnowi]

All springs are cut, just usually by the manufacturer in controlled conditions, any cutting that heats them up excessively will pretty much ruin them. The process of retempering them is quite involved and depends on the type of material used, thus i doubt any one but the original manufacturer could retemper them with any kind of gauranteed success.

As stated above if you do cut them, cut the open end (the top in your picture) as the spring needs to sit flat and to have the reducing pitch to work the way it is intended to work. I personally have had springs with 1 or 2 coils cut off, but only when using shortened shocks, and only on springs that had a very low spring rate to begin with (13 coils were on them from memory)

[OSM Garage]

I know cutting springs is stupid and that it is NOT condoned on this forum. My days of cutting springs are way behind me.

Its just that ive seen numerous times on here bout how you are able to re-set the spring after cutting and it being OK.

Im only wanting to lose 20-30mm maybe. Hence I thought maybe losing some of the keeper coils may give me that extra 20-30mm (in theory)

Sorry to dredge this subject out of grave. Such a shitty topic. Thought id get some idea's. I should have searched a bit more. Sorry team.

[isnowi]

The coils you were looking at cutting are not keeper coils, they are what make kings and other quality brands, bearable in day to day life, small bump compliance. As far as 'resetting' them after cutting, it's not something i've heard about.

The resistance on this board to cutting springs is driven by the 'gt som cuttiz bro' mentality that sees muntheads cutting 3,4, or more coils off to give their car that 'sakd owt bro' look, and then weave down the motorway bouncing around like a dog that needs to take a shit, but can't.

If it was my car, and all the measurements checked out (ie the spring was going to remain well captive, and the shock still had some travel when the spring was theoretically fully compressed, and the shocks were capable of handling the higher spring rate, i would (and have) cut a coil from the open end. Don't put any heat into the spring (don't gas axe them etc) and clean the cut edge up so that it doesn't mar the spring seat and/or go rusty. But that is only my opinion, from an engineering standpoint the only thing cutting the spring does to the spring is increase the spring rate, however it can have a profound effect on the suspension design of the car.

[shizzl]

totally agree with isnowi...

i wouldnt cut more than 1 coil off...its generally only 1-2 coils that make the spring captive.

im all for cutting of springs aslong as they remain CAPTIVE and are seated properly.

obviously cutting a coil off a spring that only has say 4 winds to it is probably not the best idea cos itll end up on the bumpstops..

[Testament]

It depends on the car also. Neither of my fiats have springs with flattened ends, it's taken up in the spring seat. Cutting factory springs and putting them back in is rarely a good idea though. Say you took some springs from another vehicle which had a different spring rate and longer springs and you cut them to fit with the desired ride height then it might work ok - it's commonly done on budget race cars. But in this case it needs to have design forethought/engineering i.e. you should know what you are doing and WHY you are doing it as it's YOUR safety/life it's going to effect if you get something wrong.

i.e. if we are having to tell you in this thread I very very much doubt you should be doing it. New springs aren't really all that expensive these days anyway, and it should be cheap enough to get most shocks shortened.

[isnowi]

It depends on the car also. Neither of my fiats have springs with flattened ends, it's taken up in the spring seat. Cutting factory springs and putting them back in is rarely a good idea though. Say you took some springs from another vehicle which had a different spring rate and longer springs and you cut them to fit with the desired ride height then it might work ok - it's commonly done on budget race cars. But in this case it needs to have design forethought/engineering i.e. you should know what you are doing and WHY you are doing it as it's YOUR safety/life it's going to effect if you get something wrong.

i.e. if we are having to tell you in this thread I very very much doubt you should be doing it. New springs aren't really all that expensive these days anyway, and it should be cheap enough to get most shocks shortened.

Good call on the expertise factor.

[Alfasprinter]

It retains the same spring rate but resets them to a lower height. They will be soft and the car will likely hit its bumpstops etc.

How does it keep the same spring rate but become soft? isnt spring rate whether its soft or hard or am i missing something?

[Brock-Lee]

stock springs are soft. you make them shorter but retain the same spring rate they become low and soft. boatyness and slam do not go together.

get custom springs made.

dun bhey

[mikuni]

It retains the same spring rate but resets them to a lower height. They will be soft and the car will likely hit its bumpstops etc.

How does it keep the same spring rate but become soft? isnt spring rate whether its soft or hard or am i missing something?

That was a little poorly worded. A standard spring is designed for a relatively large amount of travel. For example, at the original ride height the car may be able to travel 200mm before hitting the bumpstops. Once lowered, the car can no longer travel this far before hitting the bumpstops, it may be reduced to something like 150mm of travel with a 50mm drop. If you compress the springs you still have the original springrate, which will likely be too soft with the vehicles new ride height.

So long answer... how do you run cut springs legally? Are you talking cert or what? Since modifying springs in any way makes them illegal as is. Cutting or compressing.

That's how I always read the rules anyway, so keen to hear how its legal / a good idea to bother cutting springs. I would always go after market / custom springs over messing around with cut springs. Each to their own demise though.

Yes, I'm talking about certification.

Cutting aftermarket springs would surely put you past the 100mm point, which isn't that far off the ground. That is the point that requires a cert, along with adjustable height suspension.

The other wise men above have gone over the finer details for me. Other than that, I would suggest a read through the LVVTA manual for modifying suspension if you want to pursue this any further.

[isnowi]

The easiest way to explain the spring rate and the effect of cutting coils has on it is to imagine the spring is not coiled, ie it is one long piece of metal. Buy cutting coils off a coil spring the metal becomes shorter, thus more force is needed to deflect it the same distance. the number of coils and overall diameter affect the linearity of the spring, most progressive suspension springs are designed with more closely spaced coils at one end so that they become coil bound quite early in the springs compression, this effectively shortens the spring length and dramatically stiffens the spring rate.

Compressing springs retains the spring rate of the original spring (assuming the tempering of the metal is not compromised) but because you now have more coils in a shorter free length relative to the coil bound length ,the spring will become coil bound much more quickly than before it was altered.

If you are thinking holistically (do you like that word?, i'm finding a lot of uses for it lately ) about your suspension then cutting coils (IMO) and matching the shock stroke to the coil stroke, will yield a better result than just mashing some supalows onto stock shockers.

But if you are just wanting to slam without thinking about the shocks or other suspension components (bump steer anyone) then you are better off fitting springs that are manufactured for your car by a reputable aftermarket supplier, as the suppliers will have done their darndest to insulate themselves from litigation, so you can be assured that they are safe (when used as per manufacturers instruction) then as long as you are over 100mm you should be fine for WOF.

To add to the above info, it looks like you are wanting to lower your EX, if you want it to handle then you need to think carefully about how low you go as the steering box only makes the bump-steer you will get more apparent and unpleasant.

[OSM Garage]

Yes I am planning on lowering my EX Lancer. (Silver one)

Its not going to be an extreme performance car, im just wanting to get it out of the clouds and have it sit at a nice ride height so handling isn't a drama with this vehicle.

To my understanding the tighter wound coils have a greater spring rate to those that aren't wound as tight? So if I was to axe some of the tighter coils, will this affect the overall spring rate? (As in softer instead of harder)

Not wanting to "slam" it, but the aftermarket springs I have are maybe just an inch or two lower then standard. Im wanting to lose another inch.

[Brock-Lee]

spring rate is affected by the active number of coils in the spring.

So for a given spring:

heaps of coils, low spring rate

fuck all coils, higher spring rate.

By cutting off the section that has heaps of coils(the soft section) it will do fuck all as this would normally sag with car weight anyways.