I was fortunate enough to talk to one of the head research and development engineers for the Eibach Corporation last weekend at the Performance Racing Trade Show in Indianapolis. After giving me a technical overview of their entire line-up of racing springs (very innovative stuff!), I asked him about sport/passenger car springs and the ramifications of cutting them.

His first reaction was (with a German accent), “Why on earth would someone cut their springs?”

My eyes shot to the ground in embarrassment and then confidently back at him and replied, “For looks, my man. For looks.”

From there he caught on pretty quickly. Basically, he explained that cutting your performance springs is bad. Cutting your stock springs is even worse. This is for two main reasons. Performance springs are stiffer and stronger in general and are mostly structurally developed progressively. That is, the metal in the springs are stiffer towards the bottom of the coil and are progressively softer towards the top. If you were to cut a few coils off the top (which is where the cutting takes place), more weight would be distributed on less spring therefore compromising the structural integrity of the spring. If this is done, the following repercussions can occur:

Possible spring collapse
Accelerated wear on the spring/life expectancy may be reduced by 1/2
Accelerated wear on the shock and other dependent components
Very stiff ride
Lower ride height (wait, that’s a good thing, right?!)

However, if a stock spring is cut, all of those repercussions are twice as likely to happen due to the fact that they are not designed for high performance use like that of the sports/race spring companies that make them.

He went on to say that if you happened to have already cut your performance springs and nothing has happened yet, you might get lucky and nothing may happen. Perhaps just a stiff ride and possible uneven tire wear issues. However, if you live in an area where you run into salt or other corroding contaminants, it is vital to keep the springs clean. As he said before, cutting your springs puts more stress on fewer coils, which may cause stress fractures. If those fractures develop rust, then complete spring failure will happen.

So what is another alternative to cutting? He said that if you are able to remove your springs, send them back to the original manufacturer of the springs. Once received, they can apply a heat compression process to the spring and reduce the overall height of the spring without compromising performance or reliability. You may experience a slightly stiffer ride and experience some “chatter” (metal touching metal), but wrapping it with plastic wire loom can cure this.

So, the moral of the story is simple. Research what springs offer the right kind of looks/performance for your car BEFORE you purchase them! I wish I did!

It's what we have been telling people for years. But I guess we can now flame w/ a direct reference to Eibach now

screw this spring/strut crap...JIC coilovers are my next logical step.

I miss having suspension travel. Hitting the bump stops is no fun.

Very good write up and conclusion. Thank you.

so i can send my front springs to eibach and have them profesionally do this? i wonder what eibach would charge to do this.. not to mention eibach should manufacture springs for our cars that will give even wheel well gap.. my car looks like it has a few bodies in the trunk

This is interesting, since he's one of the "head research and development engineers for the Eibach Corporation" is it safe to assume Eibach does this "heat treating process" to reduce the overall height of the springs?

I never believed in cutting to begin with. Alot of my friend in the pro-modding companies who do the work what they normally do is heat the spring up with a welding torch or something similar and get it just about read and kind bring it down to a height they want.

Then they end up taking it out and re-painting it to avoid rust.

Dixit

This just goes to show you what is important to certain companies. Eibach is set up to offer true performance modifications. This is why their springs may not be as low as others. They go as low and as stiff as is appropriate for use with all the other OEM components. If you go too low or too stiff (or not stiff enough) your car may look good, but the handling will ultimately be compromised.

Lower is not always better.
Stiffer is not always better.

Sprints suck.

if you live in a city with good roads (such as suburban atlanta) harsh ride is not an issue, and they handle great, I agx's set on on 3/6 with sprints with one coil cut in the back, rides fine in my opinion, and phenominal handling.