REAR SPRING PREFERENCE ???

[jeffn]

Is a stock metal spring better than a composite? I'm thinking about replacing my rear spring an was wondering if anyone has changed, and can tell me the difference in ride and performance from the seat of their pants.:booty

 

[Copdogcorvettes]

Is a stock metal spring better than a composite? I'm thinking about replacing my rear spring an was wondering if anyone has changed, and can tell me the difference in ride and performance from the seat of their pants.:booty

Jeffn, Check past threads the pros and cons of both type springs was gone over not to long ago. I believe it was under spring replacement. It should answer all or most of your questions.

Gary

 

[Hib Halverson]

Is a stock metal spring better than a composite? I'm thinking about replacing my rear spring an was wondering if anyone has changed, and can tell me the difference in ride and performance from the seat of their pants.:booty

For a given shock absorber choice, switching to a plastic spring, will have the rear suspension less damped. Performance handling dcreases somewhat and ride gets nicer unless the car is loaded such that you're hitting the bump stops a lot.

Plastic springs offer a significant weight savings and they last longer than steel springs.

Typically, if those worried about performance handing, also change shocks whent they change to the plastic spring.

For street high-performance, you use a 300 or 330 lbs/in spring with small blocks and a 330-360 lbs/in spring on big blocks.

 

[Vettehead Mikey]

As Hib says the choice of shock has a lot to do with ride quality and handling. The original shocks are not calibrated for a composite spring and will give you a very 'bouncy' ride. I replaced mine with KYBs, very satisfied now.

 

[6880 Mike]

FWIW: You can sure tell a difference with the composite spring if you take a ride in an 81-82.

Kinder and gentler.

 

[jeffn]

Great input guys.....I'm thinking that I want a stock setup,,, but a kinder , gentler ride sounds nice too....The 79' is just a cruising car in my book.I reserve my speed and handling for my 525i....Short bursts of speed on a long strait run in the Vette is really all I feel comfortable with.....You've all got me leaning towards a composite spring with different shocks.....Front springs and shocks at the same time also.....After 30 years,the swarping effect is occouring on bridge transitions and the like.(front end bounce and sway).Not a comfortable combo.Steering and front end are otherwise tight with only 42k miles on it.Hmmmmm....decisions , decisions....:W

 

[Hib Halverson]

I'll add that, the reason shocks with more aggressive valving are required is a multi-leaf spring has an inherant damping quality from the friction between the leaves as the main leaf forces the rest of the leaves up and down.

A fiberglass spring is a single-leaf, so you losse that damping and have to compensate with more aggressive shocks if the same level of damping is desired.

Now, some above have listed the KYB as a replacement in the rear, however, I've tested plastic springs on C3s extensively and the best choice for street high performance, IMO, is the Bilstein with "sport valving". I found the only advantage to the KYB was a relatively low price. I found it's damping to be inadequate for my chassis set-up and driving style.

Lastly, the plastic spring I use on my 71 is the 360 lbs/in unit. I've experimented with the 330 and even the 300, but on a big-block the 360 is the way to go.

 

[jeffn]

Thanks Hib......That's all I need to know.A composite spring with Bilstein shocks are the ticket..I'm going to try that combo out ....If you've tried them all,what more do I need to know?..... 360 spring hu?Not 330?

 

[Hib Halverson]

Well, on small blocks the 330 may be a better choice but the choice between 330 and 360 depends on the rest of your suspension set-up. Generally, if the car has base suspension, I'd go with the 300 or the 330. If the car has F41 or FE7, I'd go with the 350.

As for the shocks, the last time I checked Bilstein made shocks with two different valving configurations "HD" and "Sport". I prefer the "Sport" valved shocks, but some people who prefer to trade a little handling for a nicer ride may want HD.

 

[jeffn]

It's just the L-42 350.....I think a 330 spring with the sport shock should do the trick....It sounds like the right balance between performance and comfort.....I want both, but the reality is, that ain't gonna happen.....I'm not gonna be beating the car to the point where I'll need total handling performance at the expense of comfort........It will be interesting though, to see how the reduced weight feels, if at all.