I see a lot of people here talk about the replacement springs available for the rear of a C3. What are the advantages of doing this?? I'm rather happy with the way my 76 rides...although the STEERING leaves a bit to be desired. I've put new bushings in the front end, and eliminated the clunks. I've put new Monroe Shocks on it to get rid of the bounce. It really doesn't ride too bad at all for car that old.

For the past four years I've driven a 92 Grand Am SE Two Door. It has sport suspension, 16" alloys and H-rated rubber. I HATE the way that car rides!! I've put new struts on it, tried different brands of tires twice, and still the car rides so bad you could drive over a dime and tell whether it's heads or tails! :mad

Then I get into my C3 and have the feeling of a good heavy car with conventional front suspension and steering. Feels Great. :flag Now, I'm in the process of paying for a 383 to drop in there, and I'm anxious as heck to get it done. Don't expect to be spending much money on it besides the motor, in the near future. :nopity But when I do, what will I gain from replacing the rear spring?? Mine has a 9-leaf currently.


[Modified by SanDiegoPaul, 2:36 PM 12/6/2002]

 

No takers on this one yet/ why not??? :confused:

 

Most only replace when needed or doing an entire suspension upgrade. I have run a 300# on a 72 with KYB shocks and my 78 has the 330# with the same shock. I like the ride and handling of the 330 better, less of a bouncy type ride. Don't run a sway bar with a composite spring. The ride quality will suffer allot.

 

How expensive is this upgrade? Is the spring the ONLY thing that gets chaged at the time?? I already have new shocks front and rear (sensatracs)

Thanks!

 

Two schools of thought:
Dick Guldstrand up in Burbank probably knows more about Corvette suspensions than anyone on the planet. He thinks that C3s should have steel springs since the original desing in 63 incorporated a steel spring. He can tune your suspension just the way you want it. I have visited him and he is a real gentleman. It's worth the relatively short drive to go to his shop for a consult.

Vette Brakes promotes composite springs of a different design than GM introduced in 80. When properly matched with properly rated shocks and sway bar(s). they perform well.

I prefer the GM desing TRW rear spring since the ride is a bit smoother.

 

I replaced my 9-leaf composite steel spring with a composite spring based on the TRW design. I chose one rated at 355 psi. I consider this as one of my best upgrades to date. The car lost about 30 pounds of weight and the improvement in ride quality was dramatic.
I feel like two things contributed to this improvement. 1.) The O.E. spring was worn out. 2.) I believe the composite spring is superior by design for my needs.
Following installation, I found that the 8" bolts supplied with the spring kit were not long enough to bring my ride height within spec. so I had to purchase a pair of 10" mounting bolts to replace them.
Don't forget to add in the cost of specially valved shock absorbers if you decide to go with a composite spring.
I received excellent service and support from the vendor that I purchased my spring from. Their ONLY downside is that they are not a supporting vendor of the Corvette Forum.
Related links:
>>> http://forums.corvetteforum.com/zerothread?id=289964
>>> http://forums.corvetteforum.com/zerothread?id=302218

I suspect that a steel leaf spring matched to your setup would also perform well and the cost would end up being about 1/3 that of the whole composite spring upgrade (spring, shocks, etc.) If the new leaf spring is not arched to the correct dimensions, you may find that your rear suspension sits higher than stock specs. which also may require longer spring bolts to correct the ride height.

Good luck with your choice. If your current spring is worn out, either choice should yeild a worthy improvement. :cheers:

 

I tried the KYB GR2 in the rear and it was way to soft and bouncy. I replaced them with the standard KYB. I also used the extra long spring bolts.

 

I am running a 340 Lb composite, TRW design rear mono spring. I love the ride, absolutely the best.
It was a bit bouncy at first, rebound happens a lot more with the mono-spring than the leaf - just a design difference.
However, once you get the correct shocks for the spring, the ride cant be beat.
For me, I went with a set of 9 position externally adjustable shocks from Mid-America. I've got them dialed in for front and rear and the ride is soooooo smmooooooooooth. Then when I want to play, I set them up to full firm and they help the car grip so well is is truly amazing.