Pete K

Hi guys,

Last friday I had a real HWFMR moment, I was driving down the highway and went accross some fairly smooth railroad tracks and heard a big bang, I look in the mirror to see a huge shower of sparks sailing out both sides of the back end.

I manage to pull it over no problem and what I found was the rear bar grinding away at the road. I managed to kick it free and with both sides loose I drove it home. Its badly bent and the new one will go in tommorrow.

My bar sits below the suspension arm as I have the PSS9 set up and TRG bars. In the picture below you can see how much below the arm is is... could anyone else check and see how much clearence they have and let me know? I was wondering if possibly the sway bar mount is a little low on the strut.

Thanks,
Pete

DJF1

It looks similar to my setup. It is supposed to be under the arm. There have been however failures to the sway bar links, snapping which sounds like what you have had. Viperbob I believe made some new sway links that would solve this problem.

993RS

Do you have an RS-type sway bar? If so, did you mount another type of sway bar link? The RS-type sway bars have different sway bar links.

PBenz

Pete,

Here is what mine looks like. I have an identical setup as you, and although this picture was taken with the car on the ground, the clearance looks very similar.

viperbob

That is really odd Pete. Your setup seems fine. I have never seen an issue like you are describing. You can see in Paul's photo, when you load the suspension, the sway bar tucks up and is no lower than the rest of the undercarriage. I am not even sure how you situation could have occured.

If your bar is bent, then it took a serious hit and I would replace the drop links and take a GOOD look at the sway bar mounts on the PSS9s for any cracks or other damage...

GratefulJED

Pauls photo has the sway link on the inside of the sway bar mount and Pete's has the link on the outside of the mount. Does that make a difference?

Flying Finn

Pete,

As others have said, your setup looks correct except that the nut on upper sway bar link is missing, is this recent photo or taken during installation?

Bruce SEA 993

I think GratefulJED has a good question there...does the RS link go on the inboard or outboard side of the mount and bar? I think that if it were on the outboard side as in PBenz picture it would have less leverage on the shock sway bar mount and have less of an ability to rotate the mount around the shock.

Anybody know more?

I am also curious why Pete K had a failure. Did the nuts fall off of the links? The install looks the same as mine except I don't know if the links are inboard or outboard. Maybe I'll take a quick peek.

Sure enough, they are inboard like Pete Ks picture and it looks like the lever arm is about 4 1/4 inches (that is the distance from the center of the sway bar link to the center of the shock). I am going to reverse them and the lever arm effect on rotating the link mount on the threaded shock will be about 2 inches.

I recall that the force is a function of the square of the length of the lever arm so I think it would be wise to have them outboard. 4 1/4" squared is 18 and 2" squared is 4 so by having the links mounted inboard allows the swaybar to exurt 4 1/2 times as much force trying to rotate the mount on the shock. Maybe that is the cause of the PSS9 mounts losening. Any more data points out there would be helpfull. Still doesn't solve Pete Ks cause tho....

Looks like an easy job too! I can actually get to the nuts with a wrench!

Pete K

Thanks for all the comments, good discussion.

TRG originally installed a new RS style sway bar and RS links when the suspension was install back in November.

I also check the suspension bolts prior to ea track day and usually once during the day. Then again when I get home and swap the wheels and pads back to street stuff. The car had about 400 miles on it since last running at Buttonwillow.

The nut was loose only because I was removing the bar and links Friday night so I could drive it to a couple social events this last weekend. I put it back in place and took a picture so I could solicit all this great advice.

Pauls picture looks very close to what mine does, only difference being the way the link is mounted outboard and mine is mounted inboard. So I guess the question now is... which way is correct?

I just spoke with Bob via land line and will be installing them the same as Pauls picture shows.

Thanks,
Pete

Pete K

I am going to put it back together and then take a look at the clearance.

I have not had any HWFMR moments since about April and it didn't look bent last time I checked. Could it have been? Sure, I could have missed it.

Thanks,
Pete

Pete K

Sorry, next time out I'll spin twice... just for you Kim.


I would have made the same driver assumption. ;-)

Pete

chris walrod

Keep in mind, only a small clearance is required at ride height. IIRC, in bump motion, the control arm moves at a slightly higher rate vs. the sway bar at the control arm. Plus, the closer to 90 degrees the sway bar is to the drop link, the better true rate..

Like Kim says, looks as though you have plenty of room to raise the mounting.

Pete K

Thanks Chris,
I put it back together the same as Pauls and it works well. I am going to raise my ride height just a tad in a couple months and will also raise the sway bar mount at the same time. When I have it all apart and on a lift I will be able to pull out the spring and cycle it through the full motion to see if there are any issues.

I also took the front bar bushings apart and greased them, I also turned them around. Prior to this I had some clunking from were the collar was hitting the inside of the suspension. By turning the bushing around I was able to move the collars to the outboard side and its all nice and quiet because the collars now ride on the bushing instead of the car.

Pete

kkim

Hmmm... I'll have to check mine as I have greased those front bushings and I still get a clunk every once in awhile. Thanks for the tip, Pete.

Pete K

Kelly, Let me know if you need more information. TRG built some new bushings last fall with one end being longer. When I last greased them Ryan told be that the long end goes inboard with the collars on the same side becasue there was not enough room on the outside. WRONG!
I installed them with the long end outside and installed the collars on the same side and it works great.

Pete