Recently up-dated rear end in 69 camaro w/ richmond 3:55 and auburn posi-trac unit. After break-in, did some hole shots and experienced wheel hop after burn-out and full traction. In other the wheels don hop immediatly, but after momentum is achieved. Is this normal? what are the causes? how to cure?

thx

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I am pretty sure that wheel hop is caused by the springs wrapping up and then unwrapping. When you hit the gas the front end of the spring tries to bend upward towards the floor, then it quickly goes back to its original position when the tires start to lose traction a bit or the spring just can't wrap up anymore.

In your situation, (at least this is what comes to my mind, someone else may have a better idea of what is going on...) you are burning out and have no traction and thus no significant spring wrap up. Then you start to get traction and the rear then causes the spring to wrap up for a second. when the spring has wrapped up enough it has to start flexing back to its original shape and hence the wheel hop.

The way to fix wheel hop is to stiffen the leaf spring in front of the axle. You could do this by getting special springs, or you could use a traction device on the springs you have if you aren't using one already. I am using the South Side Machine lift bars and they eliminated wheel hop for me. They bolt on to the leaf spring and hold it in its correct shape, keeping it from wrapping up.

What kind of car, and what year?
What spring type, multi? mono leaf?
David

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Check my web page for First Gen Camaro suspension info:
David's Motorsports page (http://ourworld.compuserve.com/homepages/David_Pozzi/)
First Gen Suspension Page (http://ourworld.compuserve.com/homepages/David_Pozzi/first_gen_suspension.htm)
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Can Am Vintage Racer

<BLOCKQUOTE>quote:</font><HR>Originally posted by davidpozzi:
What kind of car, and what year?
What spring type, multi? mono leaf?
David

<HR></BLOCKQUOTE>
69camaro, multi leaf replaced three years ago. Springs mfg by kc spring (local)

Sorry, I see you had the year and Camaro on there. I must be going blind! http://www.camaros.net/forum/smile.gif
It would have been great if they had made the front part of the spring stiffer.
You might try clamping the front ends of the spring leaves together if you have room.

I've heard having the shocks too stiff or using lowering blocks that are over an inch tall can cause it.

How about sending the springs back to be re done? They could pull a short leaf and add a longer leaf that is longer on the front half to stiffen it.
A good spring would have two leaves almost as long as the top leaf.
David


------------------
Check my web page for First Gen Camaro suspension info:
David's Motorsports page (http://ourworld.compuserve.com/homepages/David_Pozzi/)
First Gen Suspension Page (http://ourworld.compuserve.com/homepages/David_Pozzi/first_gen_suspension.htm)
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Can Am Vintage Racer

Didn't they use to clamp the front of the springs and remove the bands on the back side for traction years ago?

69er

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69 Camaro 454
71 Nova 454

If your not living on the edge then your taking up too much space

Clamping the front is a good trick. Anything that stiffens the front half of the spring.
The rubber pads around the springs are probably causing some of it.
David

------------------
Check my web page for First Gen Camaro suspension info:
David's Motorsports page (http://ourworld.compuserve.com/homepages/David_Pozzi/)
First Gen Suspension Page (http://ourworld.compuserve.com/homepages/David_Pozzi/first_gen_suspension.htm)
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Can Am Vintage Racer

Solid (aluminum) front leaf spring bushings will also help. If you were going from a non-posi to a posi this is more than likely caused by better traction due to both wheels hooking up. Better traction equals more flexing parts ( mainly springs ). Think about your rear end twisting from the traction, it twists to a point and then relieves tension by hopping. Then the whole process starts over. I run cal-tracs on my car. They come with the aluminum front bushings.

Jeff

<BLOCKQUOTE>quote:</font><HR>Originally posted by Balboni:
Solid (aluminum) front leaf spring bushings will also help. I run cal-tracs on my car. They come with the aluminum front bushings.

Jeff<HR></BLOCKQUOTE>
Jeff, waht are Cal tracs. Can you describe them physically. How they work ? are they too visible from the side / rear? Curious may locate and install. Going to replace shocks this weekend. If that does'nt worl will have to install a cal trac or similar system.

Cal-Tracs are traction bars. Check out http://www.calvertracing.com/info/info.htm.
They do hang down from the side. I prefer these to other traction bars. Cal-Tracs changes the pushing point on the car by redirecting the turning action (spring wrap-up) of the rear axle through the a Transfer Link into the Front Pivot. The Front Pivot resists turning motion and also controls the bending of the leaf spring at its thinnest section. The front pivot is mounted directly to your front leaf spring mounts. There is a bar that connects to the lower shock mount and the front pivot. This emulates a Four link system. Check out the diagram on this web page and it will give you a good idea how they work. One of the nice things about them is that they easily adjust for track use and street use (some flexing).

Jeff

Jeff

Hey Balboni, hows the ride? is it any stiffer going over the bumps in the road?

69er

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69 Camaro 454
71 Nova 454

If your not living on the edge then your taking up too much space

wow this is a small world... my motor came out of johns red camaro on that caltrac info page... he highly recommends the caltrac's. i am looking into them to stop my wheelhop issues with my 5 speed BB combo.....