Anybody have a solution to the inner portion of the spring rubbing the shock body? right now it has S&W 2.5" id, 12", 130lb. Shocks are Koni double, aluminum body.The spring is compressed just over half shock travel at race weight. I don't mind spending more if it fixes the issue. Or should just think about it as a replacement item. The car has lost no ride height at all. I haven't pulled them off yet to measure the free length.
Doug

Put a little grease on it and let it rub. Unless its rubbing really Bad. Rotate the spring to a different position, maybe.

Different manufacturers have different ID of springs. I've always found ZERO interference issues with Chassisworks springs on any shock I've thrown them on. I don't like any type of interference with the shock. Jusy my .02

I agree they shouldn't touch. It didn't always do it. The springs themselfs are bowed.
Doug

Probably about ready to break. Replace them then.

Ya....they need to be replaced if bowed....or platforms are cranked up more than 1" from full loose. If you have to crank up platforms to get the shock in the middle of its travel....you have the wrong spring rate.

I'll be a little more precise.

Lets say you have a 12" 130 lb spring. That 130# spring is compressed to 11" inches it measures 130 lbs of load.

The way the spring is correctly installed on the shock is to loosen the platforms. Install the spring on the shock. COMPRESS THE SPRING 1" to 11" installed on the shock. Lock down the platforms and DO NOT touch them. Install the coilover on the car. Let down...drive or jounce the car to settle suspension. Now...block up the rear tires on blocks or put car on drive on lift. Measure from bolt center to bolt center of coilover. Koni will give a spec measurement for your given shock for bolt center to bolt center....if your shock measures SHORTER your spring rate is too soft....if it measures LONGER than spec...too stiff. This is the CORRECT way to measure spring rate on your car. DO NOT CRANK UP the platforms...all your doing is faking the shock into thinking its in operating range....when all your doing is making for coil bind in your suspension. You wouldn't add 1/2" of shims to a valve spring to get and sitffer seat pressure would you?...same difference.

Hope I made it undrstandable

For some people spring rate is voodoo or That's what ________ said i needed....funny thing is...they dont know your car on a telephone.

Thanks for taking the time for that input, mike

Way back when I set this car up you sent me these instructions. They were set up that way and haven't changed except for being bowed.
Doug

Doug.. I had a spring bow.. actually both were
doing it.. I assume it was a quality issue..
I dont recall the brand name but I changed them
out and the problem went away... the springs
that are on there now are still fine.. when I
pulled them you could see they were bent

Cool...then it's a quality issue.How did the set up work for you?

Cool...then it's a quality issue.How did the set up work for you? [/quote]
Been 1.240, 3345lbs, footbrake, 10.5 bias slick.
Doug

Been 1.240, 3345lbs, footbrake, 10.5 bias slick.
Doug [/quote]I'd say thats pretty darn good ...

Sounds like the springs are toast. Not all springs are the same. Cheap no names typically won't last as long as good ones. Take them off and check them. If they are not square or have lost ANY free length, junk 'em. I've come to the point where I see coil springs as consumables like valve springs, slicks and spark plugs. They are usually not replaced as often as they should.

Not to start a crap storm, but shocks have a small window of where the installed length should be. That window moves some depending on the type of suspension (4 link, ladder bar, leafs) and how the car is used (street, drag race only). A heavy spring will only be compressed a small amount to hold the shock at that correct length at ride height, while a lighter spring will need to be compressed more to achieve the same result. A lighter spring will also store more energy to help make the suspension more "lively" IF needed. (Think about a smaller torsion bar on the front to help get the front suspension moving, same effect). Lots of folks see that spring rate choice as a tuning decision that is affected by power levels, suspension type, gear ratios and trans type, tires, desired aggressiveness of the suspension, and many other things. Likewise, some people will run the springs at different compressed lengths from one side to the other depending on how they want to set the car up, distribute weight, etc.

When you use a lighter spring and crank up the platfroms to work the shock in that window it's the same as adding a crap load of spacers under a valve spring to achieve the operating seat pressure of the valve. ... then...coil bind occurs. Same thing happens with coilovers. I've seen the coating completely knocked off of springs and racer says it blows the tire off at the hit....uh...ya...because you made a solid block out of your spring. Over the years I've seen some things that would make you shake your head. Why are shocks and springs such voodoo? And why is the first thing someone does is crank the crap out of platforms? And why are racers only strapping down the rear axle and letting the car bounce thousands of miles...then say their shocks didnt last.
I hope people realize that the really fast cars that are dialed in have travel shocks and race shocks... it's amazing how beat up I've seen some shocks.

There is a window to play within.. usually its
a 1/2".. I believe thats on all mounts.. as you
know there is a small amount you can change to
stay within the window... you either move the
shock or move the mount.. if you want to be
correct