whats the difference between the prokit and the sportlines besides the different lowering hight someone said proggressive or linear. Something like that, please someone with the knowledge about springs hook me up Thanks

 

i jsut put my prokit on, and they are definitely progressive...cant speak about the sportlines, but all i know that is difference is teh sportlines slam the car right to teh ground...

 

Ok, The primary difference between the two is going to be the amount of lowering. I would suggest checking with Eibach to verify spring rates for both sets of springs. I found the following information on a personal website (not Eibach, and I can't verify that this is correct info). This site lists the front springs for the pro kit at 400 inch lbs (400 pounds to compress the spring one inch, the standard way to show spring rate) and the rears at 94-160 in lb (progressive rate, 94 in lbs at the beginning of compression, and 160 in lb as the spring gets fully compressed). This same site shows the Sportline springs at 360 in lb front and the rear at 80-137 in lb. I would suspect that these numbers are reversed. Usually, as you lower a car, you will need more spring rate to keep it from bottoming out. However, this is just a guess (based on a website that I can't verify being correct....that makes for alot of "ifs"). Most importantly, if those spring rates are correct, the difference in the two spring kits will effectively be the ride height. I don't suspect that anyone would be able to tell the difference in rode quality based on spring rate differences alone. But, the sportlines will place you even closer to the bumpstops. Any time the vehicle contacts the bumpstops, your spring rate increases dramatically (the springs themselves don't change, but the spring rate "seen" by the vehicle increases). This increase in spring rate (effectively "bottoming" the suspension) can make for a slightly uncomfortable ride...and that is the part that you will likely notice. I have lowered my Z28 about 1.25 inches and I do drag the front air deflector (the part that hangs back under the bumper and deflects air throught the radiator) over driveways and such. For a daily driver, I don't think I'd want it any lower (but that's just my opinion). I am also running much stiffer springs and I still feel the bumpstops sometimes, so I suspect you will feel them even more often with either of these spring kits. The ProKit usually gives an acceptable ride (I ran a set on a 3rd gen F-body) and will improve your vehicles handling characteristics. Sorry this is so long....you asked for info....I hope this helps answer some of your questions.

Kevin

 

Anyone running sportlines have any views or information about the style of spring?

 

I guess no one here is running sportlines.To bad I want sportlines at least I thought I did? Anyone have feedback on sportlines from experience?Please let me know.

 

I do, they bottom a lot. I'm going to try tightening up the preload on the hals. It's worth it to me as I love the handling, but never tried the pro kit.

 

I'm running the Sportlines. I also have the SLP Y-pipe and the Wings West ground effects kit. I'm using my stock front airdam. I didn't want the off road look where you can see the tops of your tires so I opted for the 2 1/2 inch drop which I'm very happy with so far. There's one place where I drive that I bottom out the rear snubbers at 45 mph so I installed the Airlift 1000 air springs in the rear springs at 20psi cured the problem and gave me an infinate tuning of the rear suspension to compensate for luggage, coolers and such.You definately have to test the waters when you first install them. I also have to keep close tabs on the concrete stops in parking lots because of the ground effects. The car handles like a go cart. I'm satisfied. Hope this helps. Good luck!