[fiscus]

I'm putting a 383 (sbc) in a '82 AMC spirit that is equipped with leaf springs. I'm gonna be swapping in a new differential entirely (8.8" ford), and I figure while I'm in there I'll try to do something to beef it up so I can get a good launch with the bigger motor. I was thinking of copying a regular traction bar like the one in the photo I attached below, is this a good design? What is the deal with the U-bolt clamp that grabs the leaf half way up? My primary use for this car will be regular street driving. What is the reccomended way to attach them? I was thinking of welding them to the bottom plate where the shocks and swaybar mount. From searching I already found that I want the rubber part to hit under the spring eye..

I also found that people clamp leaf springs, does this work well with traction bars? Does it eliminate the need for them? Does it make the car ride rough?

[KULTULZ]

What is the deal with the U-bolt clamp that grabs the leaf half way up? My primary use for this car will be regular street driving. What is the reccomended way to attach them? I was thinking of welding them to the bottom plate where the shocks and swaybar mount. From searching I already found that I want the rubber part to hit under the spring eye..

I also found that people clamp leaf springs, does this work well with traction bars? Does it eliminate the need for them? Does it make the car ride rough?

The style illustrated is referred to as Slapper Bars and are good if designed/installed properly. You want the rubber snubber to contact the spring eye and not the spring itself. The snubber is adjustable for street and track. The U-Bolts shown keep the bar asm. from tilting too far down on say deacceleration so they will not trip on the pavement.

Firmly clamping the forward section of the leaves is an old and cheap hot rodders trick and does make the forward section solid acting as a traction bar (using an adjustable pinion snubber increases the effectiveness).

Is this car being built for street use or full race?

[fiscus]

It will 99% street driving, so I don't want to compromise the ride too much.

[KULTULZ]

Then this style is adjustable to give you differing degrees of ride and traction. Cheap and easy, just the way I like my women...

[xntrik]

If I were you I would try clamping the forward leaves before purchasing the bars. It might do all that you require for far less expense and work.

Make clamps of 1/2 x 1 1/2 strap with the bolts at the edge of the spring on each side and secure with 3/8 grade 8 bolts. Stop tightening when the clamp starts to flex. You will need 2 clamps per spring. One for the second leaf, and one for the third leaf. You don't need to remove the existing clamp.
You might notice a slight ride change, but I bet it will be insignificant.

An optional thing that I do is to reverse the 2nd and 3rd leaves under the main leaf which puts their longer rear end up under the forward spring eye, and the clamp the leaves..... even stiffer. Then you usually need only one clamp that does not have to be real tight.

The slapper bar spring plate replaces the one already on your car. So it bolts on using the axle u-bolts. Judging by your rust, you might have to purchase new ones. More cost. Don't start the job without having them handy. If you don't use them you can always return them. You might get one side off and then have to go hunt for u-bolts.

As stated the rubber cone snubber is to contact the spring eye. Measure carefully before installing. I bet the bar itself is not long enough to reach that far. A common problem. That is why you see all the Novas and Camaros with the snubber 8" back on the spring, and it bends the spring. The only solution is to weld on more rectangular tube to make it longer.

A little trick is to put a piece of hose on the bar-u-bolt where it contacts the spring to prevent a pop sound when it contacts the bar.

[fiscus]

Can I just slide the leaves forward or do they have some kind of special curve that only lets them come forward when they are reversed? I think I will try that before slapper bars.

Also would it be a good idea to make a pinion snubber?

[timothale]

each spring leaf has a hole and there is a thru bolt under the moumting plate. be carefull driving it on the street until you get the feel of it on corners and when on hard decelleration. some setups can lift a rear wheel on hard corners

[xntrik]

Originally Posted by fiscus

Can I just slide the leaves forward or do they have some kind of special curve that only lets them come forward when they are reversed? I think I will try that before slapper bars.

Also would it be a good idea to make a pinion snubber?

Tim,
Never heard of that wheel lifting thing.

Must pivot around the through bolt like he said. Use grade 8 bolt if replacing.

It works... 98% chance you will not need a pinion snubber. I never have on any I built.

If I were you I would just try the clamps first. Then if you need to, reverse the leaves.

[timothale]

I had a nailhead buick in my willys. I was an engineer at Ford and got looked at unfriendly when i parked it at the company the rear traction bars were clamped tight to the spring near the eye. nails pounded into the rubber bushing to tighten it up. great straight line traction but it would get squirly fast when you let off throttle on a turn. The Ford Thunderbolt fairlanes were famous for being hard to handle. I always liked the traction bars with a pivot at each end with clamps both front and rear on the spring. goodd traction and ok on road handling

[xntrik]

Originally Posted by timothale

I had a nailhead buick in my willys. I was an engineer at Ford and got looked at unfriendly when i parked it at the company the rear traction bars were clamped tight to the spring near the eye. nails pounded into the rubber bushing to tighten it up. great straight line traction but it would get squirly fast when you let off throttle on a turn. The Ford Thunderbolt fairlanes were famous for being hard to handle. I always liked the traction bars with a pivot at each end with clamps both front and rear on the spring. goodd traction and ok on road handling

What you describe is the old SouthSide Machine Co. LIFT BARS. (they also made slappers, etc) The forward end clamped solid around the springs essentially making them a ladder bar....... which of course binds SEVERELY in any body roll...... hence the T-Bolt ladder bars and your problems.

What I am talking about, and what Fatmans does is semi-flexible.

I'll see if I can pull up a pic to post.

SouthSide Machine LIFT BARS = no rubber snubber, clamp solid to spring. If you look carefully you will see 2 spacers under the main leaf, since the 2 and 3 leaf does not go that far forward, but you will also see that the main leaf is bent UP from the pressure. The only flex is in that front 6 inches of spring.... no wonder it bends.

If you flip the next 2-3 leaves front to rear so they stick farther forward, then clamp every leaf together, you get a very stiff semi-flexible spring bar that acts like a semi-flexible ladder bar. That is what I do, and Fatmans has emulated. Minimal roll bind, and acts like an anti-roll bar.

http://www.mustangii.net/ssmfaq.asp

[xntrik]

http://www.popularhotrodding.com/tec..._diagrams.html

Here's a link into a simple rear suspension article. You might like to read it.

Just back the link into the other pages.

http://www.popularhotrodding.com/tec...pension_guide/

[KULTULZ]

PLEASE HEED!

Originally Posted by timothale

• be carefull driving it on the street until you get the feel of it
  
  
• on corners and when on hard decelleration.
  
  
• some setups can lift a rear wheel on hard corners

This gentleman's suggestion is very pertinent to this discussion. When one modifies a suspension for full competition and then expects to drive the vehicle on the street, one must take precautions. Clamping the front of a leaf spring or using solid traction devices negates the design of the spring. It will be a solid bar instead of flexible as designed.

Drive it easily (especially hard de-acceleration and cornering) until you are comfortable with the new handling characteristics of the vehicle.

I just want to bring this to attention of this thread without starting another involved technical discussion...
_______________________________________________

Am Looking For Factory/Aftermarket Speed Parts For The MEL (MERC-EDSEL-LINC-TBIRD) Engine Family (383-410-430-462) Produced From 1958 To 1968

Also Early FORD Special Service Tools

-Mercury-Edsel-Lincoln- Engine Forum

[IanRiordan]

Road safety is important. In about 1983 I saw a dead cat hanging off the r/h slapper bar on an HT Holden Monaro.

[jimfulco]

Probably put it there as a warning to all other cats. They used to hang dead coyotes on fence posts around here.

[IanRiordan]

Yeah, we hang wild dogs and foxes on the fence here too. Fluffy must have run during the wheels up launch.