rdrman

My 74,L-82 gives a decent ride as far as the front go"s.The rear end is harsh mainly over the steel strips on the highway or small bumps.Is this due to the tires,265/70-15 ? Or the rear spring?,which I"M pretty sure is the original spring.Shocks are fairly new and look like koni"s.Is the rear spring something a novice can do?Do"nt want to go with a fiberglass as my exhaust is close and have heard that this will contribut to its failular.As far as steel go"s I"m looking for a smoth ride ,no racing here.Which will give a smoother ride a 7 or 9 leaf spring?Anyone chang there"s and see a big differance in the ride? :confused:

Captain Morgan

It's probably the steel spring. A 9 leaf is a softer ride than a 7 leaf but they will both transfer road vibration just because they are steel. The best way to minimize that is to go with a fiberglass monospring which you've already stated that you don't want to do. Different shocks may help too. Just because they're Koni's, doesn't mean they're good. They could be worn out or just not the proper shock for your suspension.

Edit: As far as replacing the spring, it depends on your definition of novice. If you have some experience turning wrenches and you can follow a tech manual and have a torque wench (knowing how to use it helps), then yes, a novice can replace the spring. If you need any pointers, don't hesitate to ask. I'd hate for you to break the ears off the diff cover just cause you weren't sure but did it anyway.


[Modified by sharklover, 7:56 PM 10/7/2001]

rdrman

Will most likely change the rear shocks while I"m under there I forgot to add that the tires are goodyear eagle st"s if that makes a differance. As far as the 9 leaf springs do they come in differant rates? If so do you want to go with a higher or lower number for the spring rate for a smoother ride?

Captain Morgan

The steel 9 leafs are all the same rate which is 192 lbs/sq in (or close to that) You want a lower number for a softer ride but again, you need shocks to match the suspension.

rdrman

Delco shocks were the OEM so .unless anyone has a better opinion.....,Seems all shocks have either a prefprmance write up or a general all round ,write up.No one publishes there rates,that I have seen.So its kind of hard to tell the differance between any of the brands out there> :eek:

flynhi

Paul Kisinsky of Vette Brakes told me that 80% of a C3's ride quality was from the rear spring.
Many, many are using fiberglass rear springs with better ride and no problems.
Personally, I prefer TRW OE type, but many others prefer Vette Brakes.
Air pressure in your tires will also affect ride quality. Experiment with lower pressures down to about 28lbs.

apple76

I just replaced the original rear spring with a 9 leaf. Also replaced the
shocks with the Delco's. The new spring also raised the rear end about an inch. Didn't realize how much the back end was sagging. I'm happy
with the results and the ride. One word of advice. Get the HD differential cover. There's a good chance the ears will break on the original no matter how careful you are... :eek: Good luck...

Ganey

Your tires are too tall. 255/60/15 are correct height. You need correct rear spring for sus.- 9 std., 7 FE-7 or VB equil. for either. Don't worry about VB, many of us are running them w/ no problems. VB FE-7 equil. for about 20 yrs. w/ hard life & currently Delco Performer shocks.

:cool:

ddecart

Here's my reply from this thread: http://forums.corvetteforum.com/zerothread?id=161171

When I bought my car it had a VB 330 lb spring on it with the gas-adjust shocks. That thing was very bouncy. If those were the recommened shocks, someone needs to learn how to tune a suspension. :eek:
I replaced it with a 7 leaf steel spring and the ride is much improved IMHO.

The main difference between a steel and a fiberglass spring of EQUAL spring rates is the presence of interleaf friction in the steel spring. If you compress a steel spring, the leaves rub on each other. This is basically built-in-damping. You have to overcome that friction before the spring does ANYTHING. Small bumps won't get there, so you'll feel those more.

I'm not sure what the force-deflection curves look like for comparable steel and glass springs, although I think it'd be interesting to see how the spring rates change over the wheel travel range.

So....much of the small bump stuff in the rear IS the spring. But that's not to say that you have the proper separators (friction reducers?) between the leafs on your spring.