Shredding Sway Bar Bushings
08-28-2003, 02:17 PM
#16
Three Wheelin'
Join Date: Oct 2001
Location: Seattle, WA
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Hugh, the factory chose the front spring to work with 1986 vintage high performance 205/60-16 street tires. You likely have the 245/45-16 MPSC tires in front which probably are stickier than true race slicks were in 1986. With this extra grip, you are getting more suspension movement than the 968 M030 sway bar was designed to deal with. The reason you see the front inside tire nearly off the ground is because the sway bar is lifting it off the ground.
Last edited by Steve Lavigne; 08-28-2003 at 02:33 PM.
08-28-2003, 02:23 PM
#17
Nordschleife Master
Originally posted by Oddjob
28N/mm works out to 160lb/in
21.8N/mm is 125lb/in
I used 1N = 0.225 lbf, 1mm = .0394in, double check my math.
28N/mm works out to 160lb/in
21.8N/mm is 125lb/in
I used 1N = 0.225 lbf, 1mm = .0394in, double check my math.
Opps, my bad. I remembered the conversions wrong.
08-28-2003, 03:34 PM
#18
Rennlist Member
Thread Starter
Steve, in the end I think you've got the answer.
Everyone has good points about no one else reporting a similar issue but I don't really know of anyone else with my exact setup, either. It's the only thing that's really changed on the car. I went from 225/50/16 S03's on the front to 245/45/16 MPSC's. The difference in grip is substantial.
I'll keep looking for other causes just because it never hurts to check over your equipment, but I'm fairly certain I need to think long and hard about going back to street tires vs. suspension upgrades.
Everyone has good points about no one else reporting a similar issue but I don't really know of anyone else with my exact setup, either. It's the only thing that's really changed on the car. I went from 225/50/16 S03's on the front to 245/45/16 MPSC's. The difference in grip is substantial.
I'll keep looking for other causes just because it never hurts to check over your equipment, but I'm fairly certain I need to think long and hard about going back to street tires vs. suspension upgrades.
08-30-2003, 07:56 AM
#20
Rennlist Member
Thread Starter
Yeah, I looked into that. Markus Blaszak has a great writeup on what causes control arm and balljoint failure on his web site.
Looking at the evidence he presents, control arm failure due to stock springs and stiff sway bars seems to be localized to the early steel arms. Of course, given my luck, I'll prove that nicely wrong...
So just to update anyone who might be interested, I've decided to go with Delrin bushings on the sway bar. I hope this isn't a "mask/band-aid the real problem with money" move but after spending some time examining the front end, it really does look like the bushings just aren't up to the rigors of my type of usage. I'm also looking into the sway bar bracket support brackets that John Hajny is offering.
Looking at the evidence he presents, control arm failure due to stock springs and stiff sway bars seems to be localized to the early steel arms. Of course, given my luck, I'll prove that nicely wrong...
So just to update anyone who might be interested, I've decided to go with Delrin bushings on the sway bar. I hope this isn't a "mask/band-aid the real problem with money" move but after spending some time examining the front end, it really does look like the bushings just aren't up to the rigors of my type of usage. I'm also looking into the sway bar bracket support brackets that John Hajny is offering.
