Traction Bar or Adjustable Pinion Snubber??

I got some wheel hop on my 69RR. Any suggestion which way I should go Traction Bars or Adjustable Pinion Snubber ??


Thanks Tom C.

Neither, make or buy some clamps for your front spring segments. Id suggest two on the passenger side front, one on the driver side front. And also maybe one each on the rear of the axel on both sides.

Thanks for the Reply, Not sure what you mean by Clamps !!!


Tom C.

Never ever use traction bars on a Mopar!

What springs are on there now? If they are old original springs then perhaps an upgrade is in order. Hemi springs would be a good start or Super Stock springs if you're serious about drag racing.

The pinion snubber may or may not be something to use, opinions vary. Clamping the front leaves together like Sport says is a cheap and easy tuning trick.

Spring clamps

http://www.manciniracing.com/caspcl.html

Similar to what the factory used.

Caltracs can be used successfully.

These are not the type of clamps im referring to. The clamps are more like two flat steel bars tightend by bolts that are just beyond the width of the springs. Much more clamping power then these clamps shown in the link.

IMO, Clamps or different springs are your fix.

1.El cheapo, clamps. And they can work.

2. More bucs, SS springs

3. Caltracs.

All I use is the Super Stock leaf springs. No pinion snubber and I made sure the front part of the springs are clamped. My 63 hooks fine like that on 9" radial slicks. I have seen alot of guys run pinion snubber which to me can be kind of a bandaid to help hook if the springs are worn and not working. My car hooked no better or went any faster with a pinion snubber so I dont use it since I run the 3400 lb SS springs. I have not seen many Mopars ever use traction bars as they usually dont work so good on Mopars and thats why Mopar came out with the pinion snubber. But if your SS springs work right you wont need any additional parts on it just the SS springs. Now Cal Tracs work great but they work best using the mono spring that comes with them from what I hear. Ron

Caltracs are noisy and much too harsh on a street driven car. They work phenomenally on a smooth race track. Pinion snubbers, when properly adjusted, are way to harsh on a street driven vehicle. I learned this from several decades of experience.

I run slapper bars on my '68 Barracuda with two passenger side Super Stock springs and a 1" lowering block. I had to modify them so they were adjusted properly.

I know, I know, they don't work on Mopars. LOL

I guess the reason I just beat a Hellcat in a flag drop drag race to win the Willow Springs Drags at Spring Fling was my GM 200R4 transmission. My car only had 410 hp at the time too.

The bottom line is they work awesome, ride only slightly stiffer and if you paint them satin black, most people will not tell you how they don't work.

Even Bob Tarozzi, the designer of the Super Stock Springs signed off the set-up of my car. He said they didn't use them because of weight. A pinion snubber is lighter and works great on a smooth track.

Wheel hop is really hard on all of the drive train parts, driveshaft, tranny, rear end, U joints axles and so on, not good I would replace the existing leaf springs with better ones, what kind of driving do you do mainly to induce wheel hop? Is it a 4 speed or automatic?
Pinion snubbers where intorduce on Mopars in 1957 when they lowred the cars closer to the ground to prevent the pinion U joint from hitting the drive line tunnel, not for traction
Fix the problem, don't bandaid it

My RR is a 4-Speed with 1970 HP 440 That Dyno at 425 HP and 500 ft.lb torque. It has new hemi Springs on it and what about clamps ??/I do not drag the car and but once in a while would like to spin the tires
Mostly just long drives

Thanks Tom C.

My RR is a 4-Speed with 1970 HP 440 That Dyno at 425 HP and 500 ft.lb torque. It has new hemi Springs on it and what about clamps ??/I do not drag the car and but once in a while would like to spin the tires
Mostly just long drives

Thanks Tom C.

I'd have to agree here. I added a Pinion Snubber to my 440 4-spd car, and it launched awesome. However, in normal driving it was a major pain. I took it off. I was and still am running factory 440 replacement springs in the car. But, if I wanted to race more, would definitely consider SS springs.

Your car looks kind of high in the back for stock hemi springs. Does it perhaps have airshocks on it? If not then are the shocks long enough? If they are airshocks or if the shocks are topping out then you will always have wheel hop.

I'd like to see someone like AndyF develop a retractable pinion snubber, so it can be deployed or retracted on the fly from inside the car. Something simple and robust that locks in either the extended or retracted position with the flip of a switch. It would need to have some range of adjustability, and when retracted stays out of the path of the suspension movement.

It seems like even a cable operated knee-like lever inside the snubber body would work.

On your deal buy a good set of leaf springs designed and intended to be used like you want I'm not sure if Mopar still offers a set for a 1964 to 1970 B body 4 speed car for all around high performance drinving like you want to do I bought a set of the Mopar S.S. road race type leaf springs for my 1966 Coronet, they are the shorter front half length like the A bodys are so the front spring hangars would need to be replaced to keep the rear end in the stock location if you want to do that. I didn't use them as I moved the leaf springs into the rear sub frames and moved the rear end forward two inches, which required reshaping the front fender openings
I'm sure your leaf springes are worn out so replacing them will help the car a bunch, if you want to try a new set first before adding clamps do that If you want to add the clamps later I use 1/4 thick by 1.0 inch wide flat stock steel and drill 3/8 holes in them on each side and use 3/8 bolts of the proper length for each clamp, I place them on the front half of the spring in every where I can (the tire bulge will, may, hinder using one on each side near the tire bulge ) on the front of each shorter leaf springs to clamp it to the main leaf. Do it with the weight of the car on them, don't jack it up on jack stands with the rear end hanging down You can jack it up and put jack stands under the rear end axle tubes and under the front suspension so it has the weight on the suspension to do that to be able to get under it to work on the car
Let us know what you do and the results

No air shocks but I got new shocks from Napa, Any suggestion on a type of shocks to get ??

Tom that is one sweet Roadrunner as I love how it looks and sits. Thats a car to be very proud off. Ron

Longer and stiffer. I bet they are way too short. Aftermarket HD shocks often are.

Seems like many options have been laid out for you. There are many ways to resolve this. We can all agree your current leaf springs are too weak. Stiff shocks help too.

The solution with the least drawbacks is a pair of Super Stock springs and a pair of stiff shocks.

A pinion snubber remove ALL suspension travel on the street. As for the clamps, leafs want to slide. You need to clamp these hard enough to force them not to because they want to. When they do slide, the clamps wiĺl hold your car down after suspension compression and hold the car up after suspension compression.

AndyF - why such conviction with the traction bars?

GoMangoCuda - I installed new ESPO Springs 'n Things stock springs on my 72 Imperial and it raised the car about the same as TomRR's Road Runner; about 2 inches.

I'd try a cheap set of clamp on slapper bars. The idea that you can't use them on Mopars is just plain stupid. It's a piece of metal with a rubber bumper on it, it doesn't care what you put it on. Are their better choices? Sure. But in the end all you are doing is stiffening the front section of spring.

Any car guy alive in the 70s knows slapper bars were a Day 2 item on most every leaf spring street car no matter what brand it was.

I can honestly say that I have owned and raced a lot of Mopars and have never experienced wheel hop. The first question that I would ask you is if the factory installed low pinion snubber is in place. If it is, I am a bit surprised that you have wheel hop, especially with new Hemi springs. If the factory snubber is in place, I would try using the spring clamps on the front sections of the leafs and see how that helps. I ran an adjustable snubber for years on the street with few problems, but if you hit a major bump, you felt it! I sure would run the adjustable snubber before I would put traction bars on it. Like everyone has said, if you decide to go with SS springs, that will eliminate the need for any of the other fixes. Personally, I think you can make what you have work.

The theory on slapper bars on a Mopar is that they can cause the rear axle housing to twist. Might work out that way with consistent use on a drag strip, but I don't see it as an issue on the street.

Wheel hop is caused by the leaf spring loading and unloading (the front 1/2 of the main leaf is twisting) because the rear axle is rotating and the weak spring is giving in both directions and is whipping back and forth lifting the tire off the ground as it whips. Clamping the ends of each leaf on the front 1/2 of the leaf makes it very hard for the main leaf spring to twist because it has the other leafs stiffening it. What is used to clamp the leafs together isn't as important and the actual clamping is. I've used the screw tightening type of hose clamps successfully.

Slapper bars are bolted to the leaf springs on both sides of the rear axle, and the rubber end sits against the leaf at the front end, basically stopping the mail leaf from twisting. Slapper bars can cause the leaf spring to bend at the point the rubber contacts it, if there is a lot of movement before the rubber contacts the leaf.

The axle housing concern is because the rear axle rotation begins at the driveshaft, in the center of the axle housing. The adjustable pinion snubber is bolted to the housing above the driveshaft connection and it makes contact with the floor pan before too much axle housing twist can occur. Since the traction bars, and leaf spring clamps are all at the leaf spring area, the housing can twist more before it is controlled, and then the control is pretty abrupt. The super stock springs are stiff enough they eliminate the main leaf twist before it can happen, and the axle twist is softened by the spring resistance rather then a mechanical stop. Mopar always suggested both the super stock springs and the adjustable pinion snubber.

As always, most traction issues are addressed as a full racing situation, and deal with the most extreme results that can happen. Street action seldom sees the extreme results that full racing does, however, time does take its toll eventually. If your heavy street racing every night, all night long, extremes happen much quicker then an occasional once a week romping, unless your luck sucks.

I suspect clamping the ends of each leaf on the front 1/2 of both springs will probably solve the wheel hop issue. Gene

Nicely explained. I would love to see someone with AndyF's type of talent design and sell a stout, compact, retractable pinion snubber, so we could have a smooth ride on the streets and easily remotely extend it when its time to launch.

Chevy's a Fords with rear leafs use symmetrical lengths, Mopars do not, the front half is shorter and thereby stiffer, sort of a built in traction device. Wheel hop hasn't really been an issue in any street Mopar I've driven.

I ran a snubber for nearly 40 years with clamped springs a on various cars. I made the clamps out of 3/8" x 1" steel with 3/8" grade 8 bolts. Used 2 in the front and one on the rear. I didn't have the cash then, and still don't to buy super stock springs or anything else . Note my Barracuda launching off the line with clamped springs and a snubber. You can't tell me it doesn't work.

I just wanted to THANK EVERY ONE for all the Help And Advice !!



Thank You All

Tom C.

I made my own clamps, but some crash derby guys have found some cheap clamps here. They are actually shackle straps but can be used as a clamp bracket. You cant beat the price, add in your grade 8 bolts in your needed length from any hardware store.

http://www.etrailer.com/Accessories-and-Parts/TruRyde/TRSL350.html

IMO, you have nothing to lose by trying some clamps first. Easy and cheap. I think 5 clamps would be enough. But Id buy enough plates for 6 clamps.

So you would need 12 plates @ .75 = 9.00
12bolts,nuts if by the pound, ??--= 5.00

So you use 5 or 6 clamps per side?

And do you space them evenly or bias towards the front where they flex the most?

Thanks, Joe

Sorry, No, Not per side, but usually 5 Total should be enough, 3 on the passenger side and 2 on the driver side. But you can start with 3 on Each side. 2 in front, 1 in back Each side.

You can dance them around to different points to vary the control. You space them to best control the flex. So you wouldn't put them right next to the axel or right at the front. Use your head on the best leverage point for the clamp.

Without looking, I believe Mopar suggested that you clamp the end of each spring leaf on the front 1/2 of each spring pack. The longer spring leafs will have more effect then the short ones. Gene

This is a timely thread for me. Just started driving my '65 Belvedere and I think I have problems. As I ease into the throttle on a roll, the car feels like it stops accelerating when I hit about 75% throttle. I thought it was just spinning the tires but I got under there today and found that it had broken the rubber snubber off of my Mancini pinion snubber and that the diff had hit the exhaust.

Now I'm wondering if what I was feeling is the diff jumping off the ground. The leafs are original, I think, I left them in because I liked the stance of the car. Would SS springs raise the rear of the car at the curb?

Added one clamp to the front and one clamp to the back of my leaf Springs

Wheel Hop FIXED !!!!!


Thanks Again For All the Advice !!

Tom C.

success tastes really good ! glad you got it fixed and relatively easy at that !