tarett swaybar stuff broke ..., anyone else had problems? Options

[john rogers]

The upper mount being tight against the sway bar is what I was refering to as there is no sideways movement it appears. If you get some new heim joints, I'd say to put the car up on jack stands in the front and test the A-arm travel with the bar hooked up on both sides and also with one side unhooked to see what is binding and what kind of clearances there are. This might mean devising a way to push the A-arm up to simulate full braking compression and pull the A-arm down to simulate a hard corner. This would be the only way short of mounting a video camera down there to see what is happening. I did this 6 years ago when we put the sway bars in the race car to make sure nothing was binding.

[SirAndy]

QUOTE (john rogers @ Aug 4 2005, 03:39 PM)

This would be the only way short of mounting a video camera down there

a video camera, eh? (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif)

[airsix]

QUOTE (SirAndy @ Aug 4 2005, 02:43 PM)

a video camera, eh? (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif)

It would be cheaper and easier to use a pencil, paper, and geometry.
Bottom line is that heim joints are not designed to see huge angle changes. They are intended for MINOR angle changes.
Put the U-tabs back in the correct orientation and run the bar at a possition that keeps the geometry correct. If you can't run the the bar at the stiffness you want without putting the heim joints into bind then you need a different weight bar.

-Ben M.

[SirAndy]

QUOTE (airsix @ Aug 4 2005, 04:26 PM)

If you can't run the the bar at the stiffness you want without putting the heim joints into bind then you need a different weight bar.

no really. problem here is that i don't run the bar at just one setting and that's it.

the car is also my daily driver and on the road i like to have some understeer, however, for the AX course, i like some mild oversteer.

i adjust the bar frequently. for the street usually full soft (which put the hime joints in bind on the stock setup), on the track stiffer.

i'd like to get the car balanced so it's neutrual in the middle and i don't need that much adjustment either way, but i'm not sure that'll ever happen.

i went with a adjustable sway bar so i could *adjust* it.
what's the point to just have one setting? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

(IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) Andy

[eeyore]

The problem is that the upper heim joint is fixed in space inboard/outboard wise, but the lower end in moving in/out through its travel. Added spacers to give the upper joint greater articulation doesn't really change the geometry. As a matter of fact, pushing the upper heim joint outboard would make the situation worse.

As for why this is a 914 specific problem, I think the target application for the bar was the 911. It just happens to fit in a 914. Mostly. As long as you don't run the u-tabs sideways.

[McMark]

Did the heim joint run into the UTab or the spacers?

Seems like if the spacers weren't so large, you'd gain another 5-10 degrees of freedom.

[SirAndy]

QUOTE (McMark @ Aug 4 2005, 05:08 PM)

Did the heim joint run into the UTab or the spacers? Seems like if the spacers weren't so large, you'd gain another 5-10 degrees of freedom.

on the top?

yes. no spacers on the top, just large washers. the heim joint on the top hits the washers long before it reaches it's maximum angle ...
so yes, there's probably at least 10 deg. more to each side in there ...

on the bottom, the heim joints hit the top of the u-tab and deformed the spacers ...
(IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) Andy

[McMark]

On the bottom. The top seems irrelevant, since it's not binding.

This picture seems to clearly show that the UTab isn't the problem, the spacers are. At least from where I'm sitting.

[SirAndy]

QUOTE (McMark @ Aug 4 2005, 05:27 PM)

This picture seems to clearly show that the UTab isn't the problem, the spacers are. At least from where I'm sitting.

yes, with a new part sitting on a nice glas table, sure ...

on my parts, in the car, under load, the hime-joint *DID* hit the top of the u-tab and deformed the spacer ...
(IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) Andy

[Demick]

QUOTE (SirAndy @ Aug 4 2005, 04:38 PM)

the car is also my daily driver and on the road i like to have some understeer, however, for the AX course, i like some mild oversteer. i adjust the bar frequently. for the street usually full soft (which put the hime joints in bind on the stock setup), on the track stiffer.

You've got something backward. If you want understeer on the street, you need to stiffen the bar. For autox if you want some oversteer, you need to soften the bar.

[Ira Ramin]

Lets keep in mind that my picture is with my u-tab. Andy’s may be different. So are you saying that the rod end is hitting both the u-tab and the spacer? If so, then there should be room to cut the u-tab back enough to clear. Additionally, I may be able to modify the spacers to get enough additional motion to fix this. I think that it will at least help, if not resolve the problem completely.

It appears that some cars have no problems and some (two that I know of so far) do. I’d like to figure out why there’s a difference so I can come up with the best solution. The other car that I know of, with the limited adjustment range, is local to me. Maybe, if I ask nicely, he’ll let me come by and check it out.

[jonwatts]

I wonder if this is all just a matter of the factory U-tabs not being uniform but good enough for factory sway bars?

Thanks to Ira for giving this proper attention and not taking our comments as criticisms. Sometimes group engineering can be a good thing (but not usually).

[SirAndy]

QUOTE (Demick @ Aug 4 2005, 06:10 PM)

You've got something backward.

yeah, the other way ... (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

on AX i ran full soft (sometimes even disconnected the bar) and on the street i ran it stiffer (towards the back) ...

i'd like to get my suspension dialed to the point where i can play with all of the bar for AX and just set it on full firm for the street ...

but that's another thread ...
(IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif) Andy

[SirAndy]

QUOTE (Ira Ramin @ Aug 4 2005, 06:20 PM)

I’d like to figure out why there’s a difference so I can come up with the best solution.

i believe the u-tabs came with your kit as those a-arms didn't have tabs on them ...
i'll try to take another closeup of those tomorrow.

for now, here are a few closeups of the (deformed) spacers ...
NOTE: each of the spacers was the outside spacer on the lower himejoint.

[SirAndy]

sideways

[Demick]

QUOTE (jonwatts @ Aug 4 2005, 06:24 PM)

I wonder if this is all just a matter of the factory U-tabs not being uniform but good enough for factory sway bars?

Remember that Andy's are not factory u-tabs. Are we sure that Andy's u-tabs are placed properly?

Also remember that the optimum placement may not be where the factory u-tabs were placed. This is an aftermarked sway bar and may have the drop links positioned slightly differently than stock (further outboard or inboard).

Demick

[Demick]

so clearly the heim hit the spacers before hitting the u-tabs. That's some pretty good deformations.

Demick

[SirAndy]

QUOTE (Demick @ Aug 4 2005, 06:59 PM)

Remember that Andy's are not factory u-tabs. Are we sure that Andy's u-tabs are placed properly?

that's a question you'll have to ask brad as he welded them on. he did use a factory u-tab equipped a-arm as reference and i'm pretty sure he got them welded in the correct place ...

and yes, IIRC those are Ira's U-Tabs ...
(IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) Andy

[eeyore]

It looks as if those u-tabs ARE too far inboard. According to my (3rd) spare set of factory a-arms, the bolt hole should be even with the inside corner of that tubular brace on the a-arm. (No camera, so I get to play with Paint some more)

[Eric_Shea]

Those U-Tabs look to be about 1/2" too far inward from "both" of my cars with stock tabs.

To try to explain... my outer edge is almost directly over the a-support that comes into view on those pics and is welded to the arm. (does that make sense? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) )

Both my cars have the factory mount placed "outward" by what appears to be 1/2". NOW... they're "both" 911 A-arms on the GT and the RS so... I don't know if that makes any difference.

I'd go take some pics but I don't want to piss off the Sir with my clearly superior photographic skills (IMG:http://www.914world.com/bbs2/html/emoticons/w00t.gif)

(actually, I'm too fuching lazy... I will if you need or request "Oh Sir One")