is it a good idea or bad and if so could any body guide me in the right direction, because the front spring is so hard to compress....

 

There was just a BIG discussion on this. Please search. Also search for 'lowered my ride for $24.95' and see how to do it.

MikeR

 

thanks...................

 

If you spent $24.95 to lower your Crossfire you have spent $24.95 too much.

 

Personally, I would never recommend to "cut springs." The Crossfire or any car for that matter when originally designed the ride, drive, and handling qualities were chosen specifically. Care and engineering goes into choosing the spring rates and damper rates. When buying after market springs to lower for increased performance, the new springs are professionally engineered and tested to match the vehicle.

When cutting springs one changes the rates.Hints, ride quality, breaking distance, and handling can be greatly diminished. This DIY can be unpredictable.

This is just my opinion, and I thought I would offer my 2cents. All I can say is do your research.

Correct and well done performance comes with a price tag.

 

Not again!

 

Amen!

Prepare for the hoarde of unwashed spring-cutting masses to come tell you the error of your ways...

(see here - just got the staples out of my... yesterday...)

Go read that thread and see if you believe what you see...

 

Lots here seem to think it's a good idea. It's not. But it's your car. Follow the link in my last post on this thread - you can see my opinion and also the vast "wisdom" surrounding this idea.

 

To be quite honest, I do not think it is such a good idea. I read the other threads about all the mathematics and science behind the springs (not too difficult)... but to make it easier:

Springs are expensive, especially OEMs. Not sure the price, but if my old car's springs were expensive, I should think a car which is basically a Mercedes would have expensive springs too.

You cut those, and you'd better like the results. Otherwise you damaged perfectly fine parts on your car... and now have to go buy new ones.

And as ppro said, there are lowering springs. It would be easy to just try those or ask around about what you are looking for looks wise and performance wise, rather than cutting up your car's parts!

It is just a fact of more things can go wrong than right in this case. But people have done it on here to their Crossfires and they seem to like it. You could buy lowering springs, try them on... if you like them good. Then you can sell the OEM springs and probably break even on all your expenses.

 

hate to chime in but i just had to say "moderation" is the key to succesfull spring "modification"........sorry ppro......

 

This may not be an option for anybody who's really looking to lower their car. But I've noticed my car has "settled" over the last 40k miles.
More than a few Crossfire owners have even asked me if I lowered it. I can't say for sure, but I'm guessing its dropped more than an inch.
Come January, it's going to be 5 years old, so I doubt if anybody wants to wait that long. But keep in mind when you decide to lower your car, it's going to eventually get lower.
As Sowardcustoms said...moderation.
https://www.crossfireforum.org/galle...hp?photo=12643

 

When in doubt, ask an expert - like a spring manufacturer:


Sent: Wednesday, December 03, 2008 2:15 PM
To: ppro
Subject: RE: H&R SPECIAL SPRINGS



Hello Paul-

I noticed you have not received a response back from you’re last question and I apologize! When you cut a spring the structural integrity is damaged. People will argue this but if you look at most springs there are dead coils and then there are active coils. Each serves a purpose in the working condition of the spring.

Some will argue that the dead coils serve no purpose which is half true, the main purpose for dead coils is nothing other than provide enough free length to keep the spring tight when the perches are at full rebound! Then you have the active coils which are the working portion of the spring!!!

You also have to take into consideration the spring rate is now compromised, when determining spring rate the height of the spring as well as the number of coils is used in the calculation. So when you cut a spring not only are you damaging the strength you are also destroying the handling characteristics!

If you have any questions please let me know,

Sincerely,
Stephanie French
H&R Special Springs
Technical/Sales
E-mail: Stephanie@hrsprings.com
Phone360) 738-8881
Fax: (360) 738-8889

 

ppro, don't take the following personally, as it wasn't your letter.



Bullhockey. A spring cut with a bandsaw is not damaged, except for the removal of paint.

Quote:

People will argue this but if you look at most springs there are dead coils and then there are active coils.

Bullhockey. There's no such thing as a dead coil or an active coil. A spring has coils at various wire diameters, spring diameters, and coil amounts per inch. A spring also has ends. Some ends are flattened and ground flat, others are full coils throughout the length of the spring (like Crossfires). If you cut the end of a flattened, ground spring down and do not again flatten/grind the end to match the original, then you have done the job wrong. Fortunately, on the Crossfire, the springs are wound to the ends without flats

Quote:

to keep the spring tight when the perches are at full rebound!

This is the only factual statement in that entire sentence.

Quote:

You also have to take into consideration the spring rate is now compromised

Bullhockey. Compromised implies that it has become worse. Wrong. Wrong. Wrong. The spring rate has been increased, not "compromised".

Quote:

damaging the strength

We are living in the 21st century not the middle ages. Modern science shows us that the metal in springs have a near isotropic composition. Cutting the end off with a bandsaw doesn't damage the strength anywhere.

Quote:

you are also destroying the handling characteristics!

Explain to me how increasing the spring rate of a suspension "destroys" the handling characteristics. Properly accounted for, increasing the spring rate is exactly what people want (stiffen up the suspension.)

There's so much hyperbole in that email it's almost entirely clear that it's a sales piece. The one thing that aftermarket springs buy you is a determined spring rate with the length of the original spring.

 

ditto, sonoronos...that was a grt response...any spring over time can, will start lose some strength, but I don't see that happening anytime soon on our little light cars...and I won't cut but a half a coil when I do mine in a few months...

 

How do you reach that conclusion? That sounds like it would be right IF the spring is a progressive rate spring. But I keep hearing the springs are not progressive on the Crossfire? So which is it?

 

Crossfires have linear springs.

I'll have to define some things before I stick my foot in my mouth:

Linear Spring: A spring manufactured with a single spring rate by definition a function of the number of coils between ends, the cross-sectional diameter of the spring and the diameter of the wire used to make the spring.

Progressive rate spring: Discretely speaking, a single spring composed of multiple spring rate linear springs, by definition increasing in spring rate as compression increases.

Cutting a linear spring does two things:
1. It decreases the length of the spring
2. It increases the spring rate of the spring, the value of which can be determined by decreasing the number of coils in the spring rate equation.

Cutting a progressive spring is a little more complicated, as it matters which end you cut. You could end up with a seriously degraded spring rate if you cut the wrong end.

If you cut a spring, the spring rate will go up - therefore, the correct tuning would involve changing the dampers and antiroll bars to suit.

 

And this is where I disagree. This is the root of my divergence with your otherwise valid list of stipulations.

You keep saying this but don't cite how this point is derived.

The rate of a plain old spring should not change if it's cut, but it would affect the amount of travel that occurs for a given input force. That's the crux of my objection to cutting a spring.

The premise of my position is that in order to support a given amount of travel for a shorter spring, the spring rate would need to be higher to yield the same travel for a given force.

I just don't see how the spring rate increases when the spring is cut and I am not getting any math or a practical example to support this.

Surely the book or practical experience you draw this from has more info?

 

regardless of who wins your argument...I'm cutting a half coil in the front and rear, and I feel very safe in doing so, or I wouldn't do it...the replacements will not do what I need them to do...this is a keeper for me, and I am the only driver...I will not go any further than the half coil, because other parameters will change too much...I am only looking at lowering it an inch, maybe just a little more, then upgrades the shocks...that's it...nothing more...cheap mod for me, and I think it will help just a little in handling on the track...or I wouldn't do it at all...moving on w/ this mod...thanks for all your posts, pros and cons......

 

F = spring force.
G = torsional modulus of the material.
d = wire diameter.
n = number of active coils.
D = mean (average) coil diameter.

Therefore the spring rate of a spring does not vary by length but it does vary by number of coils. The equation shows that spring rate has an inverse relationship to the number of coils.

In truth, the above equation is the simplified equation because it is only used to compare the spring rate between identical length springs. To more accurately reflect what is happening, one has to equate a coil spring to a torsion spring.

Apparently, a coil spring is equivalent to a torsion spring which has been wound up into a coil. Therefore, the true spring rate is equivalent to a coil spring flattened out into a torsion spring, which means the equation is actually k=G*d^4/L, which shows the same inverse relationship between spring length and spring rate.

(I only learned this recently while studying the subject, you and I discussing this inspired me to look it up - arguing is good for something

 

HYDRAULIC FLOOR JACK: Used for lowering a sports car to the ground after you have installed a set of Motor sports lowered road springs, trapping the jack handle firmly under the front air dam.