Factory springs modify?! Do or don't?
 

I was thinking to cut about 2" off the factory springs...Do ro Dont? :eek2:

suspension experts should be better able to answer this question, but isn't cutting spring more for those wannabe street racers who have no money? i've seen a civic with cut springs, what happened is it was crossing an intersection, and the exhaust was just hitting the ground HARD, sparks were flying behind the exhaust...........

don't do it!!!

hahaha...I love that effect when sprks are flying! just like Formula1 cars.

I wouldn't do it, but just asking if any one ever done it. :razz:

DON'T


...unless you like the nickname "Bouncy". The is what you will be doing in short time. Bouncing. The pistons in the struts/shocks will bottom out. Thus you will lose all compression and rebound....and bounce on the springs.

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YOU'LL BE SORRY:sad: You have to go through all the same steps to remove & re-install the springs. If you can't afford $250-300 for a good set of springs, save your $$$ and wait until you can. Cutting the springs is a loser ricer move:roll:

You'll simulatenously increase spring rate too.

Due to the shape of the front springs if you cut them they won't fit on the spring seats on the shocks.

--->kenchan: you won't increase the spring rates because the stock springs are "linear"

The problem is you lose your full-extension pre-load, if you hit a big whoop-te-do, there's a chance your springs can fall off the seats!

--->rl48mini: you are correct; the shape of the front spring prohibits you from chopping it and getting it back on the car seated correctly.

Overall, cutting springs is a BIG NO-NO. Scrape together the change under the couch for a real set of lowering springs that are engineered correctly.

ryephile- being linear does not matter... each coil will compress a certain amount. If you take out one or two coils you also take out the compression
amount, thus ending up with a higher overall spring rate.

oops, that's what I get for posting on an empty stomach :razz: :lol:

Think of a long piece of PVC pipe, say 20 feet. It bends easily. Now cut that piece in to one-foot sections. Now try to bend one of those.

Its an exagerated example but the principle is valid. If you shorten the length, you make it stiffer. Cutting two inches off will probably make it so stiff it won't be safe (let alone comfortable).

:sly: Having cut 1 1/2 coils off my front springs on my 77' Blazer that definitely wasn't the results I got.

....it also weighs ~1400lbs more.

Suspension mods
 

First, on cutting springs... absolutely not! It's a really, really bad idea, for all the reasons listed in the other posts, along with one everybody forgot... you'll blow out your shocks fairly quickly, and if you are lucky, maybe damage the suspension mounting points when you hit a bump hard enough.

That said, as a test, when I bought my MINI, I installed shorter springs to lower the ride height and stiffen things up. In spite of what retailers will tell you, and even tuners, this too is a bad idea. Your factory shocks are not matched to the shorter springs, and no matter whoose springs you use, you will not have a predictablely good ride. True, the appearance is great, but under certain suspension loads, you'll get all sorts of funky things happening. The least of which is that your shocks won't handle the travel or the spring resistance, and before they fail early, they will always seem a bit bouncy. (This, I say from experience! Live and learn)

My recommendation... save your money and do all four shocks and springs in an integrated kit. True, it will set you back between $800 - $1600, but I promise it is worth the money... if you can live with a harsher ride in cities and over rough roads... we have lots of them here around DC. If you can't afford this, save money till you can, but don't cut corners with tuning a MINI, especially not where the suspension is concerned.

Hope this helps!
Mike

I don't think its been said yet, but don't cut your springs. Buy some good springs, the prices of em are coming down or at least there are more options.:smile:

B

Cut springs are illegal in my area and are not recommended.
So the answer is -just say NO to cut springs.

Coil overs would be nice but more costly.
Most of us that have lowered springs of about 1" front and rear are doing well on stock shocks. At least for now. Will be watching to see how that pans out over the next year or two.

the "stock shocks fail early when used with lowering springs" may well be an urban legend. nobody has explained exactly why the mini shocks will fail early and a couple of spring and shock manufacturers told me the opposite. so if you want to buy lowering springs, don't worry about wearing out the shocks early.

nnnn... well, depends on what spring rate the springs are.
Generally progressive rate works fine with stock shocks until
they are compressed heavily...that's when the spring rate is
usually over the factory spring rate and causes premature wear
during rebound.

what exactly wears faster and why does it wear faster?

The fact that the shorter springs allow the car to sit ~1" lower than the stock shocks were designed for automatically means that the shocks are under 1" more compression all the time than they were designed. Over time this will take its toll on the shock, and reduce the life.

this isn't an engineering answer, just more guesswork.

take the springs off the strut. displace it 1", then move it back and forth 1."

next displace it 2", then move it back and forth 1."

what exactly is the difference in what wears?

[edit] and as one suspemsion company engineer told me, you could even make the case that lowering springs, if they are stiffer, wear the shock out LESS than stock springs because they give LESS motion for any given load!

if you lower the car, other things being equal, you reduce the amount of available compression travel (not so good) while increasing the amount of available rebound travel (not so useful).

If you also soften the spring rate, it is even more likely you can bottom out the shock on a hard bump.

If you cut the spring to reduce the overall height, you may lower the car (reducing compression travel) but you will also stiffen the spring rate, possibly compensating somewhat for the reduced compression travel, but notr necessarily improving handling.

I ended up rasing my car to the max available with Leda coilovers to maximize the shock compression travel, retaining a fairly soft linear spring.

The simple fact that a shock is a gas filled tube with a plunger that seals it means that while it sits under an extra inch of compression the seal will be subjected to more pressure than it generally would. This will lead to a faster loss in pressure in the tube, and reduced performance. pv=nrt stands, as the volume decreases the pressure has to increase, and the seal obviously isn't perfect.

Cut springs can work if part of an overall design. However, it is definitely a non-engineered solution unless you deal with all the variables. I ran a winning ITC 510 with cut rear springs for years. Some things to consider:
- type of cut: both torch or saw heating will change the annealing of the spring in an non-uniform manner affecting the spring rate around the heat affected area. It could allow a brittle failure under load.
- seating of the spring can change and allow "drifting" around in the seat in an uncontrolled manner causing "variable ride height" at that corner of the car.
- travel is reduced and ride height will be subject to trial and error since cutting an uncompressed spring will yield a different length under compression
- Coupling moment with the sway bar is changed
- All variables above will be significantly different front to rear since the spring rates and length are different and an equal ride height drop front to rear could result in a very ill-handling car, and possibly dangerous in an emergency
- shocks should be ok if cut is not major since the gas pressure keeps the liquid from cavitating. Fluid pressure is typically equalized around the static stop position as long as it is not too far off the base point. Cars that do only lowering springs have the same issue.

BTW - the cut springs on a 510 is an engineered solution. I'd spend the $$ for lowerng springs until some adventurous sould figures out the details of the cut spring setup for an MCS. It is not for the faint of heart.


:smile:

Hello,

Thanks for all of the information..really good information. Now I'm on M7 springs and it's lower about 1" (haven't mesured to be exact) I don't have control arms on yet!..but the car loos good and feel really good.

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