Need to replace to leaf spring on my '78 soon, is there a big difference in composite over steel? Every parts supplier refers to the composite as an upgrade, just wondering what everyone's experience with composite is.

 

Nothing wrong with going with a new composite rear leaf spring.

There only drawbacks are HEAT and some idiot tow truck person using it to pull from with the hooks and chipping it.

The ride will improve and you can custom tailor how much spring rate you want....for what you are using your Corvette for.

They are also MUCH EASIER to install. Due to being so light.

DUB

 

did the factory go to composite for cost or because they are better in many ways?
Did you see the picture the member posted the exhaust burnt up a composite spring?
I have them front and rear and as you know have had to have my poor car towed more than a fair share and I am always up on the tow driver where not to hang those hooks...

 

I've had a composite spring on mine for over 30 years, no problems. The original steel spring broke after 8 years. You will have to get different shocks to control the rebound rate. Most guys get Bilstein or Koni adjustables.

 

Dochorsepower: You bring up a good point on the need for different shocks. I'm a new owner of a 71 & have the composite spring. And I've noticed that the rebound can be pretty abrupt ( Vermont has terrible roads ). The previous owner installed new AC Delco shocks all around and probably had no knowledge of the spring's requirements.
I hope this doesn't take away from this thread, but would you explain a little more about your experience & recommendations ?
Thanks, Tim

 

I have had my VBP 360 mono spring on my car since 1985 (30+ years)...The composite spring is superior to steel in every way..weight, response rate, ride comfort, etc...GM has used composites on all corvettes since 1984 and it's not for cost savings..composites are superior to steel springs. You do need a quality shock to be matched with composites..no mass market shocks like Monroe, Gabriel, KYB...I have Bilstein Sports with my 360...

 

I really like my 420lb mono spring....if nothing else for the sheer weight of it compared to much heavier 9 leaf spring. It was already mentioned but you definitely need to keep the composite springs away from heat as much as possible.

 

YEP...just put a good nick it it and give it time...the spring will begin to shear.

DUB

 

I have heard many times that the Bilstein Sport is recommended, as well as the HD, but no one mentions part numbers. I am having trouble finding the right one for my car, I plan to go composite as well. This will be a weekend fun street car, riads not too bad, on 50-60 series 15" wheels.

 

Switching to a composite rear spring was one of the best upgrades I have done to my '79. Ride and handling are both vastly improved. I have the Vette Brakes & Products 330 lb spring and KYB shocks. They have been on the car for about 20 years.

 

I have the standard spring and couldn't stand the bouncy rebound so I went with Koni adjustables set at one turn stiffer than factory medium and it feels just like I want it.

 

I guess since Corvette switched in 84 they seemed to agree. I wonder if the agreement applies to the older corvettes as well

 

Actually the composite rear leaf spring was being used in 1981 on a Corvette. I believe the 1980's were still steel.

DUB

 

Correct DUB! 80 C3's all had steel transverse leaf springs, base and sport suspension.

The 81/82 BASE suspension only corvettes had a composite leaf spring and the gymkhana cars had a steel leaf spring. Starting in 1984 ALL C4's had composite transverse leaf springs, front and rear, regardless of suspension specified. The 81/82 composite springs were rated at a whopping 172 lbs/in...total marshmellow versus the FE7 Gymkhana sport springs rated at 306 lbs/in.

I love my 360lb composite that replaced my 7 leaf steel gymkhana spring in 1985 (292 lbs/in in 1978). The 360 VBP composite monospring rides much smoother than the 292 steel spring. The beauty of a composite spring is that the spring rate can be MUCH higher than a steel spring with a MUCH better ride/handling, its reaction time to bumps/ road irregularities is much faster (this where the bouncy nature comes from-use a quality shock and no issues) and weighs 8 pounds versus 50 lbs for a steel spring. Yes there have been some issues with delamination of the composites but that is by no means a common occurrence-witness the forum members like me that have 30+ years using a composite. My 505 NET HP C6Z06 has no issues either with its rear composite.....

 

THANKS.

I am amazed on how much my brain can remember this stuff. Sometimes I fell I am correct...but there is a part of me that wonders if I am confusing it with something else due to all the years I have to deal with.

DUB

 

Mine is an 80 and for right now, just to get this thing on the road again, I am reinstalling the original steel spring. But I did replace the old sears shocks with Bilsteins B6 - HD. I actually found them not only in stock, but a decent price and shipping on Tire Rack!