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Terrible wheel hop, can't lose it

I noticed ( and this may have no relation to your problem) On my car (93 945 t)with 235x35x19 REAR tires, that the tire pressure effected wheel hop really bad. I had a semi bald tire on the passenger side(new tire on drivers rear) on a 3 inch drop, when i put 40 psi in both tires everything was fine, 50 psi in semi bald tire on passenger side, mad wheel hop. Tires are rated at 55psi max. Like I said, just something to think about Since I did not read a mention of this. Cure was to replace tire or lower air pressure to 40/45 psi. Some times the fix is not so complicated.
 
Wheel hop on a non-leaf spring car is caused by the compression of the bushings with resulting sudden release of the energy?

On my old '79 Mustang, Lakewood made a traction bar for the Fox body. That was long ago, but it did the trick.
 
to me, it still sounds like worn bushings. you said yourself, it all worked good at the start of the season.

with the car on the ground, in first gear. lay on the ground near the rear wheel, and rock the car back and forth, look to see how much movement you're seeing with axle roll. you might be getting the wheel hop from the bushings loading up, and letting go as you lose, and gain traction. Like i said earlier, i went with heim joints in my toque rods to get rid of any of that wrap and i the axle doesn't load up at all anymore. i think between bad torque rod bushings or bad main axle bushings thats where you're getting your hop.

im not gonna dwell on whats proper and whats not, but a pan hard bar simply positions your axle laterally.. so i can't see it affecting vertical performance.

Not sure what it is worth, but this is my vote. you may need to get more aggressive with trying to rock the car, use your e brake as well as first.

dead bushings are guaranteed undampened play, don't waste your time on anything else until you know they are good.

I would bet if the panhard bushing is bad, then the lower axle bushings are toast (unless they were already replaced)

If you have not done them, now is a good time to do them.

Stiffer springs and shocks will exacerbate any issue with the bushings.

The following advice has already been given, but i will reiterate it.

When i first got into these cars, i put full poly in the back, which is a mistake unless you just want to drift and do burn outs, made my car worthless in snow and rain.
Stay with QUALITY rubber, or go with heim joints.
To me, poly was ok on the the panhard rod though, and seemed OK on the front trailing arm bushing, and front torque rod bushings, but 100% does not belong in the trailing arm/lower axles bushing imo.
+1 on tire pressure as well.

i have been a bit out of the game for a while but i think kaplan has heims for the lower axle to trailing arm bushing, someone else may too.
 
Here are a few more options besides the stuff from Ben, which is totally fine and will work. I'm just all for more options.
There's Sellholm Tuning in Sweden, ~$255: http://www.sellholmshop.se/bakaxel-bussning-240-uniball.html

You could also fab your own for cheap if you have the skills. Get the parts from PolyPerformance or someplace similar.



Wrong bushing guys.
 
Thanks for looking into more then rear axle placement.
Here's an update:

Installed adjustable panhard today, no changes. As mentioned before - new shock absorbers, springs have a preload so that won't be a game changer anymore. Ofcourse it's good news now that my axle at least is in the middle of the car, less stress for driveshaft for sure.

Took it for a spin - think it depends on tarmac, but more or less I have the same vibrations then before. More vibrations when slipping wheels on straight line, less when going sideways. Most turns felt okay, but some (which were bassicly the same speed and angle) had a TERRIBLE wheel hop. Let it go when a hop like that appeared.

But when turning slowly with welded diff you can feel that the rear axle is hopping already, kind of hard to describe this in english, maybe I will take a video of it.
Anyways, from now on I'm even more confident that those are worn bushings, have to install poly ones for sure. (Thanks to everyone who yelled that it must be rear axle angle. I still can't see how it would affect so bad wheel hop)

I will keep this updated, but since I want IRS for back I might not do a thing to this one aswell. Will see.
By the way - is the 960 IRS axle plug and play fit or cutting and welding is done?
Thanks in advance.
 
Thank you.

And yes, more power is coming, since it has EDEM cam, 16t, LS2 injectors, only MS2 is waiting in corner to be installed ha.
 
When i first got into these cars, i put full poly in the back, which is a mistake unless you just want to drift and do burn outs, made my car worthless in snow and rain.

I've been thinking about this, but can't figure it out.

Off-road we like tall sidewalls and loose suspensions for articulation and therefore traction (keeping the tires on the ground). But on the street, the priority shifts to a more controlled ride.

Is the poly-bushed rear end one step too far, from a compliance stand point, that wet traction is compromised?
 
Just found this on Ben's site:

In order to get proper articulation and to not over constrain the rear axle Volvo put voids into the rubber bushings, while this works to allow the axle to rotate back and forth with travel it makes the bushing weak and prone to ripping and destruction. Our competitors offer a polyurethane bushing to replace this Volvo bushing. While this bushing is much more durable it is also very poorly designed product that is not well suited to is installed application. The polyurethane bushings will deal with vertical travel reasonably well but they do not respond to body roll or one wheel bumps correctly. They do not pivot in the body roll direction! What this does is it causes the rear suspension to bind. When the rear suspension binds it lifts the rear wheel off the ground and reduces grip levels, reducing traction accelerating out of corners, and causing a shift in handling balance to over steer.

Very interesting.
 
Just found this on Ben's site:

In order to get proper articulation and to not over constrain the rear axle Volvo put voids into the rubber bushings, while this works to allow the axle to rotate back and forth with travel it makes the bushing weak and prone to ripping and destruction. Our competitors offer a polyurethane bushing to replace this Volvo bushing. While this bushing is much more durable it is also very poorly designed product that is not well suited to is installed application. The polyurethane bushings will deal with vertical travel reasonably well but they do not respond to body roll or one wheel bumps correctly. They do not pivot in the body roll direction! What this does is it causes the rear suspension to bind. When the rear suspension binds it lifts the rear wheel off the ground and reduces grip levels, reducing traction accelerating out of corners, and causing a shift in handling balance to over steer.

Very interesting.

Old news.
 
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