Leaf spring-composite vs. steel
#1
Leaf spring-composite vs. steel
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.
#2
Race Director
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
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
The following users liked this post:
Lee Smits (06-05-2016)
#3
Race Director
Member Since: Mar 2003
Location: Eustis ( Area 51 Bat Cave ) Fl
Posts: 11,608
Received 772 Likes
on
645 Posts
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
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 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...
The following users liked this post:
Lee Smits (06-05-2016)
#4
Drifting
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.
#5
Instructor
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 hope this doesn't take away from this thread, but would you explain a little more about your experience & recommendations ?
Thanks, Tim
#6
Le Mans Master
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...
#7
Safety Car
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.
#8
Race Director
did the factory go to composite for cost or because they are better in many ways?
I believe it was to lighten the car...and actually you can get a higher spring rate. I do not knwo WHY GM did it...
Did you see the picture the member posted the exhaust burnt up a composite spring?
YES...I have seen it before at my shop and do not need to see a photo of that. SO...making sure your exhaust does not cook the spring is up to the person doing the job. GM did have a stove shield to aid in this issue.
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 believe it was to lighten the car...and actually you can get a higher spring rate. I do not knwo WHY GM did it...
Did you see the picture the member posted the exhaust burnt up a composite spring?
YES...I have seen it before at my shop and do not need to see a photo of that. SO...making sure your exhaust does not cook the spring is up to the person doing the job. GM did have a stove shield to aid in this issue.
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...
DUB
#9
Melting Slicks
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.
Last edited by Richard Daugird; 06-07-2016 at 04:37 PM.
#10
Melting Slicks
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.
#11
Drifting
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.
#12
Team Owner
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 guess since Corvette switched in 84 they seemed to agree. I wonder if the agreement applies to the older corvettes as well
#13
Race Director
Actually the composite rear leaf spring was being used in 1981 on a Corvette. I believe the 1980's were still steel.
DUB
DUB
#14
Le Mans Master
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.....
Last edited by jb78L-82; 06-08-2016 at 07:40 PM.
The following users liked this post:
DUB (06-09-2016)
#15
Race Director
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.....
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.....
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
#16
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.