Hello,,
need some help.
have a 70 W30 4speed with bad wheel hop,
changed everything, new coil springs,shocks, new upper and lower control arms with poly bushings and it still hops, there is nothing left to change,
and help would be appreciated..

 

Tried changing tires?

 

If the rear end sits too high, the geometry of the control arms will be wrong and you will get hop.

 

forgot to mention the tires, they are new Hankooks with maybe 40 miles on them, i guess i can put on different set and see what happens,
as for the height after replacing everything in the rear it did raise about it 2 inches, about to change the shocks and springs in the front..had so many but never one with wheel hop..

 

Since the tire is momentarily loosing traction w/ the surface of the ground & then catching up again (repeatedly) it generally implies suspension geometry - generally suspension somewhere, but it can be the tires, as well. My first inclination is to consider correctly sized very firm shocks. Since you didn't state your initial ride height, I'd assume you were at OEM factory ride height? That would also imply 14" wheels without oversized tires. If you're running 15" wheels, oversized tires, and you raised the rear-end another 2" from whatever it was initially, be certain you have the correct set of shocks to accommodate this raised height - you'll most likely need a very firm set of rear shocks.

 

The four speed cars tend to wheel hop at factory ride height and higher. If you eliminate the hop via a tire change, it will most likelybecause the new tire has less traction and simply spins vs hops.

Lowering the rear of the car will help reduce hop. It can change the upper control are geometry and therefore instant center enough in some instances to eliminate the hopping.

If that does not work, or is not an option, take a look at lower control arm relocation brackets. You can use them to increase anti-squat which can also help eliminate hop.

 

Pinion angle... Preload it and the wheel hop will go away.
NO HOP bars do this. Do not go too far or you will have vibration issues with the drive line too. Upper adjustable control arms should solve your issues. Shorten the upper arms and the pinion angle wil lgo up a few degrees preloads the pinion quicker and this should make a difference.

Jim
JD

 

car has 14 inch wheel/tires with the orig shocks/springs and had bad wheel hop, got new 225/70/14 tires and still hops, changed everything in the rear and just the shocks/springs in the front and still hops, will get different tires for the rear and see what happens, will post outcome after doing so..
Thanks to every one who has replied to this.

 

Tires will mask the geometry issue. Again, if the hop goes away via a tire change, its most likely a result of reducing rear traction. You are better off addressing the suspension geometry vs. trying a different tire. In summary, there are a few options to look at:

1. If you have original rear springs, take a look at lowering the rear end some with aftermarket lowering springs.
2. Install lower control arm relocation brackets.
3. Install adjustable upper control arms and preload pinion angle. (I.e. point the pinion down toward the ground a degree or two more than an "optimum" pinion angle). For example, if your pinion angle should be -1 degree for optimum drive line angles, set it at -2 or -3 instead. When you launch the car hard, the pinion wants to rotate upward. This upward rotation puts your pinion and drive line angles at the correct positions under hard launch and acceleration vs. steady state cruising. The downside is a potential for drive line vibrations during steady state driving.