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  #11  
Old 03-01-2011, 06:06 PM
JKnight JKnight is offline
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When coupled with a well engineered lateral locating device, the composite springs are left to do a very specific job; not unlike a coil spring in a link arrangement. They are not very good at controlling lateral movement, so you have to help them out with a locating device (panhard, watt's, etc) With that done, my experience/belief is that the composite leafs do their job every bit as well as a steel spring, while having the benefit of subsantially reduced unsprung weight. That benefit should not be overlooked or trivialized, as it makes a noticeable difference.

The OP is in Denmark and can not go with a link arrangement without running into significant legal issues with the local tax-man. I will agree that the geometry of well sorted 4-link arrangement has benefits over the leafs, but many have proven that leafs can work very well in competition, even against those with link style rear setups.

I don't know if a composite spring would be worth a significant premium over a well-engineered steel spring, but I can tell you that they should not be written off as an option just because they aren't more popular.
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  #12  
Old 03-01-2011, 06:43 PM
Roberts68 Roberts68 is offline
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Quote:
Originally Posted by JKnight View Post
When coupled with a well engineered lateral locating device, the composite springs are left to do a very specific job; not unlike a coil spring in a link arrangement. They are not very good at controlling lateral movement, so you have to help them out with a locating device (panhard, watt's, etc) With that done, my experience/belief is that the composite leafs do their job every bit as well as a steel spring, while having the benefit of subsantially reduced unsprung weight. That benefit should not be overlooked or trivialized, as it makes a noticeable difference.
I'm neither for or against, if they have merit great and they have always intrigued me since I first heard of them. But... I would be curious whether they save enough weight if they require additional steel in the forms you mentioned. I suppose they may, and that steel leafs may benefit or require the same devices to perform at the same level.
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  #13  
Old 03-01-2011, 07:27 PM
JKnight JKnight is offline
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The need for a locating device can cut into your savings in terms of weight and $$ vs. going with a link setup (particularly if you go the Watt's link route), but the weight savings will still be significant.

I don't think they're the top option available for our cars, but they're a viable one given your goals and restrictions. I'm just a guy with a keyboard who used them on my car though. There is plenty of evidence that people like Mary are using steel springs on their cars (Hotchkis, Global West, DSE) and having success, so you can have good performance without going composite.
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Last edited by JKnight; 03-01-2011 at 07:32 PM.
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  #14  
Old 03-02-2011, 10:19 AM
Bryce Bryce is offline
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A watts link does not need to weigh alot. Mine weighs 8.4 pounds.
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  #15  
Old 03-02-2011, 11:00 AM
JKnight JKnight is offline
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Agreed. Even my Fays2 setup does not weigh much more than 15lbs, and all that weight is sprung.
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  #16  
Old 03-06-2011, 11:41 AM
Hotchkis Hotchkis is offline
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Originally Posted by T-T View Post
Hello there.
A couple of years where I just have followed the various posts, this is my first post on this forum.
I hope that it will give me a lot of response to my humble questions, as I will do anything to help out where I can make a difference.
I've separated my 69 Camaro and seek knowledge and new parts to make it a scary street machine, -ready to give all the "exotic" buy-cars like Ferrari and Porsche opportunities to look at my rear taillights and smoking rear tires

-----------------------
I plan to buy myself a set of composite leaf springs from VBP to my 69 Camaro.
- Those of you who have the fiberglass leaf springs already installed and running for a while, maybe you can tell me what it gives and takes. -Good and bad.
- In my Camaro, i´m planing approx 500 hp,5 speed manual and I will use the car for street and “semi-serious” weekend autocross.
- Is it possible to order the composite leaf springs 2 inch lowering rear of the car. -or do I have to do it with lowering Blocks.? .. don´t like!
- I've seen people talk about 150 to 210 pounds of pressure/strength ??? ... what can be recommended - please tell from your experiences.
-Can they break ...!!! .. -- is after all just two rods of fiberglass ... or is it??

Leaf spring link: http://www.vbandp.com/Camaro/1st-Gen-1967-69.html

Thanks for all help before I order ....??
Tom –Denmark-
Tom,
Composite leaf springs are great for Corvette front suspensions (where it’s transverse mounted) since they only need to spring up and down. As a rear leaf spring in a car like your Camaro, the spring is subjected to lateral forces where it is not as strong. The worst possible force for a composite leaf spring is to twist it into an S-shape, which is what would happen if you have a high-output engine and moderate traction. Adding a lowering block to any rear leaf spring moves the centerline of the drive axle away from the leaf spring, which greatly increases the leverage of forces that attempt to turn the spring into the shape of an S. Adding a lowering block to a composite leaf spring is not suggested.
Leaf springs like the ones we offer are extremely effective for handling. Mary Pozzi and Carl Casanova have been wiping up the competition with Hotchkis leaf springs on their Camaros.
Carl Casanova

Mary Pozzi

They have proved that you don’t have to spend a ton of time and money to have a good handling vehicle.
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  #17  
Old 03-07-2011, 11:22 AM
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Mkelcy Mkelcy is offline
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Quote:
Originally Posted by Hotchkis View Post
Tom,
Composite leaf springs are great for Corvette front suspensions (where it’s transverse mounted) since they only need to spring up and down. As a rear leaf spring in a car like your Camaro, the spring is subjected to lateral forces where it is not as strong. The worst possible force for a composite leaf spring is to twist it into an S-shape, which is what would happen if you have a high-output engine and moderate traction. Adding a lowering block to any rear leaf spring moves the centerline of the drive axle away from the leaf spring, which greatly increases the leverage of forces that attempt to turn the spring into the shape of an S. Adding a lowering block to a composite leaf spring is not suggested.

Leaf springs like the ones we offer are extremely effective for handling. Mary Pozzi and Carl Casanova have been wiping up the competition with Hotchkis leaf springs on their Camaros.
With respect, Carl ran Flex-a-Form composite leaf springs with swivel bushings for (I think) at least five years before he recently swapped over to the Hotchkis springs and was pretty sucessful with that setup as well.

Most of us who run composite leafs have found that we can run higher springs rates with less relative degradation of ride when compared to steel springs.
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  #18  
Old 03-07-2011, 03:23 PM
JKnight JKnight is offline
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Quote:
Originally Posted by Hotchkis View Post
Tom,
Composite leaf springs are great for Corvette front suspensions (where it’s transverse mounted) since they only need to spring up and down. As a rear leaf spring in a car like your Camaro, the spring is subjected to lateral forces where it is not as strong.
Agreed! And as recommended to the OP earlier, a lateral locating device is highly recommended when using composite springs.
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  #19  
Old 03-09-2011, 11:03 AM
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BMR Tech BMR Tech is offline
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What I would like to see someone do is use a set of composite leafs, Watts Link, and our Torque Arm (not the whole kit, just the torque arm). The Watts link would do a superior job of locating the rear and composite springs have much quicker reaction times than steel springs and lower unsprung weight. For traction issues and preventing spring wrap our Torque Arm is perfect for a composite spring because, unlike a traction bar, it doesn't load the front spring eye. Since it is centrally located and has bind-free articulation, the leaf spring would only have to support the car, the torque arm would handle the torque load. I would bet this setup coupled with a good set of dampers could rival any link style suspension out there...

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Last edited by BMR Tech; 03-09-2011 at 11:07 AM.
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  #20  
Old 03-10-2011, 12:51 AM
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Originally Posted by BMR Tech View Post
What I would like to see someone do is use a set of composite leafs, Watts Link, and our Torque Arm (not the whole kit, just the torque arm). The Watts link would do a superior job of locating the rear and composite springs have much quicker reaction times than steel springs and lower unsprung weight. For traction issues and preventing spring wrap our Torque Arm is perfect for a composite spring because, unlike a traction bar, it doesn't load the front spring eye. Since it is centrally located and has bind-free articulation, the leaf spring would only have to support the car, the torque arm would handle the torque load. I would bet this setup coupled with a good set of dampers could rival any link style suspension out there...

I'm happy to volunteer to try this out.

I've got a '67 Camaro that's got ATS tall spindles, SPC UCA and LCA, Hotchkis sway bar and Bilstein shocks on the front (no kits here), and will be getting Flex-a-Form composite leafs with custom swivel bushings (on hand), a Fays Watts link and Bilstein shocks on the rear.

The drive train will be a (roughly) 425-450RWHP LS1, Aftermarket T-56, and a 3.55:1, 12 Bolt rear (all on hand). Estimated completion is late this year or spring 2012.

With a good driver (clearly not me) it could be pretty quick.
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