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Discussion Starter #1
Went back 12 pages here and couldn’t find any info. I know they make fiberglass or some other composite material leaf springs. I think Astro vans had a CF spring?
Would these be effective with a CalTrac or SRD bar? Any experiences you can share?
 

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I ran fiberglass springs with caltracs on my 68 mustang. Installed them back in 2008ish. The company that made the springs was in the Carolinas somewhere. They specialized in dirt track stuff but did a good job giving me the right arch, rate etc..

The car hasn't run in awhile, but was 1.40 60', et'd in the 10.30 to 10.40 range. Worked well even with Goodrich drag radials.
 

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I'd like to see someone make a composite rear section for split mono springs. Ideally it would be lower spring rate than is currently available and save some weight also. I think they would hold up ok on the rear section of a split mono.
 

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I have Hyperco composites, did a few races last year and they worked great. Using stickier tires this year. Hyperco leafs you do not need cal tracs or SRD bars nor are they compatible. Composite springs don't wrap up like steel leafs do. Also much lighter than any steel leaf.
 

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Discussion Starter #5
I have Hyperco composites, did a few races last year and they worked great. Using stickier tires this year. Hyperco leafs you do not need cal tracs or SRD bars nor are they compatible. Composite springs don't wrap up like steel leafs do. Also much lighter than any steel leaf.
Could you provide more info why either brand bars are incompatible? I’m very interested!
Thank you.
 

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Could you provide more info why either brand bars are incompatible? I’m very interested!
Thank you.
Any traction device touching the leaf will weaken the surface it rests on. That's the drawback I guess of the composite leafs, not enough mechanical surface toughness.

I have found no reason to use any traction device though, they don't wrap. I moved the front spring eye up a little and that helped plant the tires.
 

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Any traction device touching the leaf will weaken the surface it rests on. That's the drawback I guess of the composite leafs, not enough mechanical surface toughness.

I have found no reason to use any traction device though, they don't wrap. I moved the front spring eye up a little and that helped plant the tires.
What kind of car you running them on?
 

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Discussion Starter #9
Any traction device touching the leaf will weaken the surface it rests on. That's the drawback I guess of the composite leafs, not enough mechanical surface toughness.

I have found no reason to use any traction device though, they don't wrap. I moved the front spring eye up a little and that helped plant the tires.
Thanks for the input. Did you move both ends of the spring up an equal amount or was the front elevated and not the rear of the spring?
Sliders or shackles in the back?
What kind of rear shock were you using? Was it a coil-over?
Rear springs only...man, I like that idea!

I’ve got an e-mail buddy in Norway (yrjo wallius), he races a AMC Rambler in NHRA SS/J. It has a 343 engine in it.
 

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Front ends only of the leafs are moved up 3/4" towars floor from stock position in the bracket as per Herb Adams mod. Rear are shackles at stock length. Delrin bushings in the frame, rubber in the leafs. Rear shocks are just the Koni Classics, set very hard. The composite leafs are pretty stiff at 225lb/in. I have no lateral locating device, no traction devices for the leafs. Yet the car feels incredibly tight and responsive, A big part of that is the composite springs shave a ton of unsprung weight. Probably about 60-70lb less than conventional steel leafs.

I might have to upgrade the shocks but have to try out the new tires first. Don't know much about other cars than f bodies below 800hp though. WHat I do might be way off on other cars. The composite leafs though are excellent upgrades. There's a reason they still use them in dirt racing.

Name of your email buddy sounds very Finnish. Got alot of racers in Finland too.
 

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Discussion Starter #11
Your right...he’s from Finland, not Norway. I just bought some Ohlins shocks. So my American Motors car is now part European. :)
 
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