Reducing ride height by "resetting" coil springs

[MetroMPG]

Another interesting article on Autospeed:

Resetting coil springs to alter your car's ride height

Want to tweak the ride height of your car? By f-a-r the most cost-effective approach is to reset the existing coil springs.
Reset the springs – what’s that, you ask?

Well, as the name implies, it’s a process that involves heating the springs until they’re red-hot and resetting their free length to your specification. The process is then finished by quenching, tempering, shot-peening and powder coating. It’s essentially a remanufactured spring.

There are two main advantages to this approach. First, resetting the existing coil springs doesn’t affect spring rate, so you can enjoy a modified ride height with absolutely no trade-off in ride quality.

Full article & pics:

Resetting coil springs to alter your car's ride height

[tinduck]

Hm.

There is a reason for the fact that most shorter springs you can buy are harder too... With this method, you sacrifice loading capacity and/or bad-road capability because your unsprung mass will more often use the whole freedom of movement it has left. With shorter, but harder springs, you get an uncomfortable ride, but hold basically on to the old capabilities regarding the above points.

Naturally, it all depends on how far you want to go... down, that is.

so long,

tinduck

[botsapper]

Replace with thoroughly engineered products. Lowering your stance requires the tuning harmony and balance for enhanced driving dynamics. Here's a proven supplier - Eibach Springs : Pro-Kit (Step 1)

[MetroMPG]

Good point.

I suppose also the owner's typical driving circumstances might dictate what approach would be best (in terms of stiffness vs. bottoming out).

[Frank Lee]

It was far cheaper for me to just cut 'em! (although I did heat juuuust enough to reshape the cut coil so it would seat nicely) And I'm happy with the ride and handling too.

I'd suspect that coil bind with these re-heighted springs could be a common occurance...

P.S. I doubt any of the "pro-engineered" kits ride/handle ANY better than mine!

[COcyclist]

Originally Posted by Frank Lee

It was far cheaper for me to just cut 'em! (although I did heat juuuust enough to reshape the cut coil so it would seat nicely) And I'm happy with the ride and handling too.

When you shorten a spring you stiffen the spring rate. Imagine standing in the middle of a 12 foot 2x4 suspended at each end. A 6 foot 2x4 would feel twice as stiff. Cutting may be a better compromise between altered height and minimum cost. Resetting wouldn't be free unless you own a spring shop.

[aerohead]

During auto shop at Taft High in the 1960s,one of our budget minded low-rider classmates decided he would 'reset' his coil springs,while installed on the car,with an oxyacetylene torch.They referred to it as 'torching the springs.'
And yes,he managed to catch his car on fire which was hilarious in a terrifying way,but not as funny as the reaction of Mr.Howard,our shop instructor,who,when he realized what was going on nearly lost it completely.
I've never heard a teacher cuss out a student so completely and without ever actually using any expletives!
Thanks for the memory!

[some_other_dave]

It's a great way to ruin the temper of a spring and weaken it significantly. At least, the home-brew "torching" is. It sounds like they may do post-treatment to make sure the metal is re-tempered, but I still wouldn't trust it. And I really would not trust myself to do it at home!!

Nor anyone else, for that matter.

It's easy enough to buy springs in just about any rate you want with just about any free length.

-soD

[Ladogaboy]

I still prefer to go with coils that are specifically manufactured to be shorter. Also, most OEM springs aren't progressive, so if you go with an aftermarket replacement that is progressive (such as the Eibachs listed above), you might be able to lower your car while enjoying an improved ride quality.

The other thing you'll have to account for is the shock/damper travel/length. If you go too short, you risk destroying the shock/damper, or at the very least, decreasing its lifespan significantly.

[Frank Lee]

The other thing you'll have to account for is the shock/damper travel/length. If you go too short, you risk destroying the shock/damper, or at the very least, decreasing its lifespan significantly.

Why's that? All the suspensions I've seen have rubber bumpers for cushioning any bottoming out. I'd think at the worst, you'd be hitting them more often than desired.

I used stock gas charged struts for my lowering job. It's been so long since I've dropped that car (about 2") I can't remember how old they are... must be going on 8 years or so with no issues.