I am getting ready to order my suspension ugrade kits for front and rear. I have an '80 L-48 and everything is still original (to my knowledge - I've only had her for about 3 weeks now). So, she is well past due for the upgrades. Anyway, I was wondering what all should be replaced when doing a suspension upgrade. I am not looking at doing highly modefied performance...just want to get the car rolling smooth and handling like it should. I plan on getting the upgrade "kits" from one of the top vendors (Corvette America, Zip, C-Central, etc.). Should I go ahead and replace the A-arms, too? I have not looked at them at this point to determine whether or not it is truly needed...but, if it is something I should go ahead and do while I am at it...then that is what needs to be gotten and done. What about shocks, springs, and the like? If you need further info on my endeavor...I would be more than happy to provide it. I just want to do things right and not purchase anything that isn't necessary at this time. Any advice you can give would be greatly appreciated!

 

Get a front end rebuild kit (poly or rubber-your choice) and just rebuild it. No need to get new a-arms if yours are ok. You can get a kit from multiple vendors. Rear suspension is a much larger job. Expect to spend at least $1500. You most likely will need the T/A's gone through (have them rebuilt or exchange them) and the best way I see to do the rest is with a kit like the one VBandP offers. Clean everything up and only replace parts that need it. New U joints in the back (spicer solid). The vbandp kit comes with just about everything you need including bilstein shocks (only way to go) and new front and rear springs of your choosing. Plus they are having a 15% off sale for a while.

Just make sure you buy everything you need all at once, you can save a lot of money only paying shipping once or twice instead of small parts as you go along.

There are plenty of threads on here you can find searching for "suspension" that will give you many different setups and installation information.

Good luck,
Sean

 

As simply restoring original performance is your main objective, IMHO new rubber bushings throughout in lieu of poly would be the right call in your case, but I'd urge you to upgrade the shocks to a set of Bilsteins. Unless your ride heights are out of whack, your springs are likely OK, but should you replace the rear leaf watch out for over-arched ones which will jack your rear up like a 4x4. If you change or add bar, several handling characteristics will be affected, which ought to be discussed before you start messing with them so you understand what you're getting into. While you're at it, don't overlook the idler arm, which is probably due a replacement, and check the steering box to see if it's in need of adjustment or rebuilding/replacement. If you're up to it, you might think about fresh body mounts, too. There's a lot of junk parts out there to be avoided, so stick with quality stuff, such as Moog ball joints... My $.02


TSW

edit - BTW, are you going to do the work yourself?

 

As long as your a-arms are true then just replacing the bushings and ball joints will make your car handle like new. There are many options now available for the front and rear suspensions for these cars but they shouldn't be considered upgrades. We have tested many but not all of the packages available for our cars in and for Vintage racing and found the stock set up to be the fastest and easiest to adjust. We even tested fiberglass springs to steel springs and found the steel spring to be faster despite the added weight. The most important part of your suspension overhaul is in the bushings and ball joints - control arm, strut rod and trailing arm. I recommend sticking with rubber but the poly is a slight performance enhancement. Below are links to our front overhaul kit and our rear suspension pages. If you have any setup questions shoot me an email with your car's specifics and I can point you in the right direction.

http://www.duntovmotors.com/FrontSuspensionSteering.htm

http://www.duntovmotors.com/RearSuspension.htm

http://www.duntovmotors.com/SpindlesParkingBrakes.htm

 

Sean pretty much hit the nail on the head. Be careful in the rear suspension due to possible side yoke play and worn bushings. If your rear is not tight, you can end up with a wandering effect and cause for many "white knuckle" driving experiences at high speeds.
Also take a close look at the upper control arm mounting points. Where the cross shaft the is attached to your upper control arm bolts to your frame. There are to bolts on each upper arm. IF the distance between the shaft and the frame are very close, and the amount of shims is very thin, you may want to have your frame stretched. IF the shaft is bolted to your frame, and there are no shims, than you should take it to a reputable body/frame shop and have the cradle stretched. VB&P sells an off-set cross shaft to aid in correcting this common problem. I would hate for you to do all of this work and find out that your camber/caster can not be adjusted because there are not any shims to allow for these alignment adjustments. Once the cross shaft contacts your frame, you can not have a proper alignment until it either stretched or the off-set shaft(s) is installed. The "spreader bars" that are offered are not intended to allow you to spread the cradle back into position. It is an aid in holding the position of the cradle and preventing any further collapse of it after it has been properly aligned. GMC "DUB"