Rear Leaf Springs ...."Clamping Them?"

Hello,

I was watching one of the car shows yesterday and they took a Mopar (Duster?) to the track and time raced it. Then they put some clamps on the rear leaf springs.

It sure looked good and it got me to thinking. I mean, they were just small clamps but they stoped the leaf springs from coiling up a bit I guess.

Anyone heard of this? I am assuming that they would stiffen the rear leafs and stop them from twisting on acceleration.

Any thoughts or experience with clamping the rear leaf springs?
I have a '66 Mustang.

Thanks, Greg.

It used to be a common trick on Mopars in the seventies. The spring design on these cars is a short front and a long rear. By clamping the front you get the effect of a traction arm, while the long rear still gives spring action to plant the tires. That is why high power Mopar cars leave the starting line like no others.

I have a 66 mustang gt and I run Eaton 4 leaf mid eye with the original style Traction Master traction bars with poly bushings.They work quite well. I made some leaf spring clamps for my friends drag truck and didn't notice a difference, but then again it is a truck. I would weld on some Traction Master bars.

Actually, if you swing all the longer leaves to the front, with
the exception of the main leaf, you don't really need the clamps,
or at least I didn't, on my old 340 Dart...

SteveL

Can anyone tell me how much room there needs to be between the shelby style traction bar and the leaf spring ? I have about 1/2 inch with the suspension hanging. Do I need to reinforce the mount points (i.e. box them in)? I am running about 400-425hp.

Thanks

Well back when they were popular they were usually called "Slapper Bars".
There were articles in magazines like Car Craft, Hot Rod and Popular Hotrodding on the subject at teh time.
I would think that starting out with somewhere around a half inch with the car sitting static on the ground and going from there. Then adjust to personal choice as you test it out.

There were also bolt on spring clamps = a pair of flat bars with bolts through the ends that were popular in the 60's and 70's but I don't think I would want to run them on the street.

The hot Mopars usually came with an extra leaf in the right spring as a traction aid also. As mentioned above Mopar did a lot of work to make their cars hook up right out of the box.

The ones I have bolt connect to the shock mount plate and the front is welded to the body, much like the CAl Trac but without the rotating mechanism on the front.

Greg,

Any idea on where to find them? They are recommended by John Calvert (Cal-trac bars) but in the 5 years I've had my Caltrac's, I've never been able to find the clamps. The ones I've envisioned are small U-Bolts, maybe 3/8" diameter that will go over a 2 1/2" spring and be about 2" long with a piece of 3/8" x 1" bar for backup. However, I've never seen these or the bar clamps you mentioned...

Russ

You can get clamps from Summit or Jegs, they're made by Mr. Gasket.

Onlythe good, If the traction bars are welded solid at the front w/o a pivot It won't work and the weld will break the first time the car moves or shortly there after. It has to be able to Pivot at the front to work.
S10xGN you should be able to find the clamps through the sources that oneofakind67 mentioned. Or a local speed shop or an older parts house that sells/sold speed equipment. Think the places that never dust the shelves There is usually one parts house in the area that never gets rid of anything untill it sells.
If there is a spring shop (suspension) in the area that you are in they can make you the clamps if you can't find them. A couple of online searches didn't show anything.

a trick we use on dirt cars is to slide the second leaf forward under the spring eye, redrill the spring, reverse the third leaf so the front ends up under the spring eye, leve the bottom leaf as it comes stock, couple of clamps on the front of the spring. This setup works well enough to yank the left front off the ground on 8 inch tires.

When It is all said and done the quick and simple way would be to stop by the steel supply and pick up a length of 3/8 x 1-1/2 flat bar. measure it out so that you can drill holes so that bolts will just clear the spring and make your own.

do a Google on "mopar super stock springs" = technology from the 50s

"Shelby type" traction masters are ancient technology that reduces wheel hop but fails to plant the tires.... Slapper bars are ancient also, and look sucky too.

Shelby used what the rules allowed..... front and rear.... that doesn't mean it was good stuff THEN or 40 years later.

Replace all those worn out rubber bushings with urethane.

Make spring clamps out of 1/2 inch thick stuff and use at least grade 5 3/8 bolts. See post # 11.