Question on Stock Rear Sway Bar & Some Mild Upgrades

slow&rusty · 07-12-2011, 07:27 AM

Hi Gang – Just messing around the car and wanted to get your thoughts on if the following two “upgrades” are worthwhile pursuing bearing in mind and I will be utilizing the stock rear sway bar (my car is an ’89 by the way).
1) Poly urethane bushings for the bar
2) Tarett Engineering sway bar drop links.

I do not want to increase pre-load to the bar such that it will eventually tear the sway bar mounting brackets off the chassis as many have unfortunately experienced.

Many thanks - Yasin

IROC · IROC's Garage

Honestly, I don't think either of these really make much difference. I would hesitate to even call them an upgrade as you would never be able to tell the difference between those and stock components unless you crawled under the car and looked at them. They're just different.

Tearing the sway bar mounting bracket has to do with the loads imposed on it, and neither of the two changes you mention above are going to change those loads in any appreciable way.

redridge · 07-12-2011, 08:20 AM

+1.... unless you go with bigger sways, you should be good with stock mounts.

KTL · 07-12-2011, 08:50 AM

I agree with IROC. Those changes will do a few things for you, but nothing that you will instantly feel as a performance improvement.

Poly bushings will tighten up the reaction of the bar, but will also squeak. Not much gained there.

Tarett's drop links simply afford you the opportunity to reduce any preload on the bar and thereby allows you to better corner-balance the car. Also their adjustable length makes it easier for you to hook up the links to the bar.

Factory mounts tear on cars with fully stock suspension all the time. So don't think that you're safe from mount failure by sticking with stock torsion bars and sway bars. Reason being is the high amount of body roll loads the sway bars so much, due to softer stock main springs (torsion bars). Even with fairly stiff torsion bars and stock sway bars you can still tear the stock mounts. This is because the car still has a fair amount of body roll.

The stock mounts fail two ways. Either the base tears away at the 90 deg. bend, or the nuts pull thru the base. Stock mounts are good enough if you reinforce the base by fattening up the 90 deg bend (or support it with a triangulated piece) and by adding additional meat to the base to keep the nuts from pulling thru. That said, they're still made of thin sheetmetal, so they're a little touchy to weld (easy to burn thru the thin metal). Nowadays the factory upgraded butterfly mounts are around $75 ea. For slightly more money you can get the Buckley Racing plate steel mounts or the Wevo cast steel alloy mounts. Both are very sturdy mounts that should last a very long time. They are both much more beefy in the base than the stock mounts.

gtc · gtc's Garage

I and others have torn the mounts using only the stock 21mm rear bar (i have 27mm rear t-bars). If you get up under there and take a close look at them, you'll see that they're pretty flimsy. And the updated factory parts aren't much better.

Edit: Kevin beat me to the punch... good to see we agree. I have a set of the Wevo RARB consoles ready to go in, and their quality really is impressive considering the marginal price difference.

slow&rusty · 07-12-2011, 09:36 AM

Good points guys and I appreciate the responses. I know the stock sway brackets tear all the time with stock suspension (really flimsy design..thanks Porsche!) due to excessive body roll. At some point I will probably just have to "man-up" and buy the WEVO mounts and have them welded in (just not there yet).

I think at this time, I will just leave things alone.
Cheers!
Yasin