E36 Owners with Hotchkis and/or JRZ suspension - Horrid wheel hop.

[Braymond141]

I'm looking for some advice on what is causing the horrid wheel hop that I've been getting post rebuild and suspension component replacement.

JRZ RS1, Hotchkis Sway Bars, TCK rear springs and adjusters, Turner bushing based LCA, new OEM ball joints, AKG poly subframe mounts, Rogue RSM, rebuilt half shafts, etc etc etc etc. The full details are in my journal if someone spots a culprit. http://www.m3forum.net/m3forum/showthread.php?t=489481

I know wheel hop is normal with IRS cars. I've dealt with the normal hop on my 96 M3 for 9 years prior to all these changes. It is so bad now that is feels like the upper control arm is twisting and tearing the wheel off the car. This is with 13psi of boost by the way. My only guess is the high pressure JRZ shocks or the Hotchkis sways (although using a larger bar should help eliminate hop). Everything was torqued using a Snap-on techangle and with the car loaded on the ground.

I have noticed that on full droop the RS1 rear shocks thunk when dropped (meaning lift the wheel and let go you get a thunk). It feels as if there is no internal soft droop stop, just a metal stop. I also cannot get the car lower than a finger gap in the rear with the RS1 (likely due to the pressure of the shock). It prompted me to call around and the only thing that was mentioned was upper control arms being on wrong (they are not). Even with the adjusters removed the car still sits above the tire (I do not want stance trash height, just noting this). Another theory was that I'm not low enough to use the RS1 appropriately. Meaning I'm too high so full shock extension comes abnormally. If that's the case a spring change may resolve this.

Car handles amazing when grip isn't an issue. In turns it steps out very smooth and is easily controlled. This is only from straight line launches or second gear WOT pulls where wheel spin is excessive.

[FastFabM3]

Have you tried adjusting the damping and seen what results that has? Also, if you contact JRZ about this, they may be able to help you with different valving or what have you. It's possible the shocks are the problem, even if the handling is good otherwise. Not saying that's it conclusively, but it could be part (or all) of the problem.

[Braymond141]

Have you tried adjusting the damping and seen what results that has? Also, if you contact JRZ about this, they may be able to help you with different valving or what have you. It's possible the shocks are the problem, even if the handling is good otherwise. Not saying that's it conclusively, but it could be part (or all) of the problem.

I have not contacted them yet and yes I have played around with the adjustment, no change. I didn't want to bug them with this as there are so many other parts involved here.

You could very well be right. I recently blew the motor so I can't test any other shocks now. While it is down I was hoping to resolve some issues. I have a set of Koni rear shocks to try, just no propulsion.

[TXBDan]

Easy on the loud pedal?

[jayjaya29]

What tires?

[matthugie]

Easy on the loud pedal?

Blasphemy!

On topic, I have the Hotchkis bars and haven't had any issues with wheel hop. What length springs are you running?

[Braymond141]

What tires?

PSS. They were never this bad prior.

[Corky325]

What do you have for rear trailing arm bushings?

I would guess stock rubber would cause wheel hop for a turboed car.

[Braymond141]

What do you have for rear trailing arm bushings?

I would guess stock rubber would cause wheel hop for a turboed car.

Brand new OEM RTABs with limiters, correctly pre-loaded. I ran poly RTABs for years and was convinced to stop.