I am not na/t yet, just 5sp with torsen at the moment. While playing in the rain yesterday I noticed that there is horrible wheel hop and as I have not encountered it in prior cars, I have no experience in what needs to be changed to get rid of the problem. The rear currently has 305x18x40 with coilovers on 8k springs in the rear. The subframe was swapped to an mkiv unit with all new control arm bushings. I have not swapped the subframe bushings or the pumpkin bushings as I have read conflicting info as to whether to go solid or not. This is not a drag car but meant for the circuit next summer. I just want to get rid of the hop and have the suspension totally dialed in before the drivetrain upgrade.

If it's going to be a road course car wheel hop will never be encountered. Don't worry.

Solid subframe bushings are useful for road course to maintain a predictable alignment but I would skip on solid diff bushings since all they do is add unneeded whine. You won't be experiencing the shock of a drag style launch so diff bushings in poly are fine.

The wheel hop issue is inherent to every IRS. Best way to reduce it is to eliminate all points of the suspension that allow flex (solid bushings). I've heard swapping to asymmetric shafts to cure wheel hop but have no personal experience with that. A custom live axle setup with panhard bar or watts link would cure it nicely too

You can't eliminate it completely.

Steve

Dunno why exactly but when I swapped wheels/tires mine went away for the most part. The stickier tires are on the car now and it has much less hop.

Really? I thought its actually worse on my slicks. It's nonexistent on my all-season rears but those spin pretty freely with a clutch drop out of boost as well.

Strange! I have no idea why it went away. The hop was all season 275's the no hop is 285 summer tires... Crazy!

I have some hop, and plan to change my tires for next season, when that day arrives I will report back on the findings of that situation. I have toe bars and heard if I added track bars it would also reduce that hop. From the stuff Ive read on hop, having too stiff of dampening will add to it, so if you get a chance try softening up your coils and see if it helps. I would but she is in the garage undergoing Studiogeeks guide to turbo heaven.

A bias ply slick will absorb most shock due to the way the side wall is constructed vs. a radial tire, which will hop. That's why all 6-speed Supra guys run slicks instead of drag radials. Drag radials tend to skip on IRS, which causes wheel hop. Automatic cars don't have this issue because they don't shock the driveline like a clutch operated transmission does.


STeve