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I just installed this version from A-Z Performance in the UK. Price may have gone up slightly due to FX rates, but they are running from $175ish shipped to US East coast (cost dependent on color). I like that it uses three strut mount bolts vs only two on most others and they have some nice color options if you are interested in looks.

I felt a difference but I drove a vert without any brace for a few weeks before installing this one. We did some yard cleanup the same weekend I did some work on the vert and the OEM bar got tossed into the dump heap during the cleaning frenzy. I have a fun after work off-ramp and before installation I could hear very faint tire noise which I no longer hear. That was without any bar so not the most direct comparison of OEM vs aftermarket - but I can say there seems to be a difference without any bar!
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I think the bar is basically 100% required - rigidity in the front compartment is severely lacking due to front frame rails that extend into space with very little structure to keep them from rotating or to tie them together. Since all cornering force is transmitted upwards, those rails will tend to twist and screw with camber. This I believe is what Qwik is mentioning - those strut towers should be tied into the firewall to prevent this, but they're not. The strut bar is Saab's way of making up for GM's budget design. GS's subframe brace further improves resistance here.

Neither of these fix the issue of not having a roof. That problem is similar, except instead of the front frame rails twisting and screwing with geometry, the car twists at the door openings so the seats and the windshield move independently of each other. The only way to fix that is reinforce the car in the middle... a cross brace somewhere... under the car, through the car... something to prevent that twisting at the sills.

I'm sure Saab was deeply aware of all the flaws in the chassis - strut towers in space, a non-boxed engine subframe, lack of structure in the cabin, etc. They mitigated things they could (strut bar...), but I'll bet when someone said, "Hey, let's reinforce the sills like on the c900" someone else said, "No, people hated having to step over them and we're not doing that again." :)
 

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I am going off the OP picture. The 9-5 Dame Edna I have the strut towers are well positioned and welded in structurally. Regardless the strut mounting bolts are a joke and barely fix and locate the upper strut mount. Adding a strut bar using those 8 mm bolts is redonkulous. Actually a 1 3/4 chromealloy tubular bar welded in transversely across the lower frame rails in front of the crank damper would be much more useful to improve torsional rigidity cheaply and easily. You could do more I am sure but it’s all about cost versus performance benefit
 

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Discussion Starter #24
strut towers welded into firewalls don’t need strut bars.IF they worked and provided torsional resistance the strut bolts would break off. Just as an aside.
Yes, I've been pondering that a bit. The whole brace bit is only as good as those bolts. A bar with a 90 degree plate that wrapped down and bolted to the front of the strut tower would be much stronger in attachment. But, the question is still whether it would matter.

I can see a bar across the engine compartment adding back some of that cardboard that was cut out of your shoe box (You left out cutting for the hood opening :). In the case of the box, it would make it more rigid so that the sides stay vertical when you push on one. So, the towers could not move towards each other.

I have to figure the stock bar does something engineers at Saab (GM) could measure. With all the cost cutting, they did, all the significant items they cut out or cheapened to save .50/car, they wouldn't have continued to put those bars in if they didn't have engineering justification. Sure, it's a sales tool for sport buyers,especially if it's shiny (aka the Camaro cited above), but that wasn't really Saab's market or that of a lot of other sedans that have them.

So, I'm guessing they do something, but measuring how much is an interesting point in the field. Whether adding anything makes a difference, a similar point to ponder.
 

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Discussion Starter #25
...This I believe is what Qwik is mentioning - those strut towers should be tied into the firewall to prevent this, but they're not. The strut bar is Saab's way of making up for GM's budget design. GS's subframe brace further improves resistance here.
Honestly, I don't think the bar helps much in a fore-aft direction. The strut tower is already strongest that way and it's probably doing little. I think it's only providing resistance against the towers moving in towards each other or in at upwards direction. The tie in at the firewall helps the bar resist lifting, which allows the torsion of the bar to resist the tower lifting. or the end-to-end strength to resist towers moving in horizontally.

Neither of these fix the issue of not having a roof. That problem is similar, except instead of the front frame rails twisting and screwing with geometry, the car twists at the door openings so the seats and the windshield move independently of each other.
There's that... and then there's also the fact that the whole front half moves up and down due to the lack of roof. That bracing would need to go fore and aft as well as from port to starboard. The left/right motion probably would not happen if the front could not move up and down. Since it does so, and even does to independently, we need cross bracing. See the red brace above :- ) .

I'm sure Saab was deeply aware of all the flaws in the chassis - strut towers in space, a non-boxed engine subframe, lack of structure in the cabin, etc. They mitigated things they could (strut bar...),...
So bottom line, short of the red brace, the best we can do is mitigate what's not there. We can't re-engineer the car. The stock tower brace, subframe brace. and maybe a third leg, will create a box that helps the part in front of the firewall resist distortion. But, even if we make that 100% rigid, it's not going to resist the whole front end moving up and down and the entire section twisting as a unit.

How much will it matter - hard to say. I'll keep it going on the back burner.
 

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Honestly, I don't think the bar helps much in a fore-aft direction.
Yeah, beyond unlikely it's doing anything longitudinally.

The stock tower brace, subframe brace. and maybe a third leg, will create a box that helps the part in front of the firewall resist distortion. But, even if we make that 100% rigid, it's not going to resist the whole front end moving up and down and the entire section twisting as a unit.
I suspect that's what GS means when they say their brace reduces cowl shake. But I think the side-effect of that is that it will smooth out some of the little distortions, but probably make the big ones worse by turning an otherwise compliant section of the car into a giant monolithic structure. I've read several accounts of brace-equipped convertibles having bone-crushing cowl shake, which is not something any of my convertibles have, even the Viggen. Lots of annoying little shakes, but nothing I would equate as bone-crushing. :)
 

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Well, the NG9-3 convertible was supposed to be a much, much more solid body. That may be, but it still has cowl shake and flexing.

I suspect that the only way to make one of these convertibles rigid is to install a proper full roll cage, the kind that you have to climb over to get in the driver's seat.
 

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Cowl shake points to such a basic structural issue it just don’t be fixed easily. C4 Corvette was horrible for that. We caged it. You are not going to cage your rag top. Even EDT lol. BobSabbit has it figured pretty much. And I did forget the hood in my box lol
 

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New here, but a added the A-Z Performance strut brace to my ‘01 9-3 5 Door (Maptun Stage 2) last week. It stiffened the chassis up for sure, but not dramatically. It takes bumps a bit better for sure, but I thought I lost some steering feel. In the end the difference wasn’t that dramatic (but it looks good). Changing all 3 engine mounts made a bigger difference for me in the handling department. This is an old chassis, it can’t compare to modern ones or even to some of its contemporaries. My dad has a ‘06 Honda Civic Coupe with 165,000 miles that still feels like it’s carved from a solid piece of granite.
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Discussion Starter #31
New here, but a added the A-Z Performance strut brace to my ‘01 9-3 5 Door (Maptun Stage 2) last week. It stiffened the chassis up for sure, but not dramatically. It takes bumps a bit better for sure, but I thought I lost some steering feel. In the end the difference wasn’t that dramatic (but it looks good). Changing all 3 engine mounts made a bigger difference for me in the handling department. This is an old chassis, it can’t compare to modern ones or even to some of its contemporaries. My dad has a ‘06 Honda Civic Coupe with 165,000 miles that still feels like it’s carved from a solid piece of granite.
Hadn't heard about those guys before. Are you in the USA or Europe?

Engine mounts are a big item, for sure. Makes the whole car seem more solid. Every little bit contributes to a more solid feel in these. Eventually they start feeling almost right :)

Do you also have a subframe brace?
 

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Discussion Starter #32
Got my sub-frame brace installed (other thread). Initial reports are generally good although I've barely tested.

  • Washboard pavement, the convertible's arch nemesis, is better but still gives some significant cowl shake, as expected.
  • Rough road (lots of pavement defects in a row) seems a little harsher. I think stiffening the sub-frame forces the vibration into my stiffened suspension and into the body now. The subframe is less of a "spring". More control is prob the upside, but more vibration too. Usual trade off.
  • Shifting seems slightly improved, which is probably due to less engine movement with the stiffer sub-frame. Note that I also have new mounts so things were already fairly good there.
  • Simple bumps like expansion joints are significantly smoother and less disruptive. Surprisingly smoother. Suspect keeping the sub-frame level and reduced post bump shudder smooths things.
  • We don't really have any long washboard corners around here, so I still search for that test bed. Expect improvement but nothing startling.
Overall, a nice upgrade and another incremental chassis improvement. It's feeling pretty good these days.
 

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Discussion Starter #34
Good article. I'll be thinking about my custom top brace net... after attending to some important and unimportant other stuff!
 
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