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Originally posted by Pascal:
Originally posted by Jeb Hoge:
I think the idea is that it "ties" the tops of the suspension components together, forming a box of sorts, which is inherently a stiffer structure than a "U" assembly.
Yes, I do understand that.
You didn't realize I'm playing stupid here... I'm waiting for the technical explanation on how bracing a car's unibody will make it resist body roll when cornering. 
That was my version of a technical explanation! 
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LOL! It's all good then! Originally posted by Plastique_synthetiX:
Kind of cutting the sho shop bar, and then welding it onto the OMP brace so that it will hold both the top of the struts and the strut tower....
I'm not liking this at all either.
There's a bushing up there to allow some movement of the strut within the tower. In motorsports they replace bushing top mounts by pillow-ball (spherical bearing) assemblies, which take 100% of the flex away. They still don't go out and bolt the shaft directly to the car's chassis, and there's got to be a reason behind that.
One of them would definitely be caster. The angle of the strut pin in relationship to the strut tower should be allowed to change. I'm throwing ideas here as to why some failures have been observed with that SHO-shop bar.
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Originally posted by Pascal:
Originally posted by Andy W.:
Jeb Hoge installed one on his 95 and noticed quite a difference.
Then it looks like the Contour's unibody doesn't age too well.. 
I'd agree that that's probably the reason that I felt a difference (although I hope no one interpreted Andy's comment as me being "night and day" about it) post-installation. I got mine from SVT ST Pete, in fact, who said it didn't do anything for his much newer car.
"Think of it, if you like, as a librarian with a G-string under the tweed." Clarkson on the Mondeo.
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Originally posted by Pascal:
LOL! It's all good then!
Originally posted by Plastique_synthetiX:
Kind of cutting the sho shop bar, and then welding it onto the OMP brace so that it will hold both the top of the struts and the strut tower....
I'm not liking this at all either.
There's a bushing up there to allow some movement of the strut within the tower. In motorsports they replace bushing top mounts by pillow-ball (spherical bearing) assemblies, which take 100% of the flex away. They still don't go out and bolt the shaft directly to the car's chassis, and there's got to be a reason behind that.
One of them would definitely be caster. The angle of the strut pin in relationship to the strut tower should be allowed to change. I'm throwing ideas here as to why some failures have been observed with that SHO-shop bar.
Correct Pascal. The caster change in a Macpherson strut suspension is substantial when turning the wheel. The angle of the strut changes as you turn the wheel. So if you constrain the strut (by using the SHO Shop Brace) you'll fatigue the threaded portion and eventually snap it off. What's even worse is that when you make a turn. one struts tils forward, while the other will tilt backwards. So not only are they being consrained (in the SHO Shop desigh) but you are inducing opposing forces on each strut - very bad!
2000 SVT Turbo 295hp/269ftlb@12psi
#1 for Bendix Brakes Kits!
Knuckles rebuilt w/new bearings $55
AUSSIE ENDLINKS $70
Gutted pre-cats $80/set
A lack of planning on your part does not constitute an emergency on mine!
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Originally posted by Pascal:
Chassis bracing has but one purpose: enable the suspension to perform its work.
No, it has another, more important, and largely overlooked purpose: NVH reduction. Bracing raises the natural frequency of the body structure and that "feels" better to the driver. The amount of movement allowed by the flexibility of the body structure is, in many cases (most, I'd argue) not enough to significantly affect suspension geometry but it IS enough to make the car feel jiggly and potentially allow uncontrolled wheel motion on the inside wheels in a corner. But a lot of people seem to think there's enough displacement of the strut towers that the car body kind of rotates around them in a corner and that's just complete [censored]. If that were the case we'd all be losing paint off the hood and fender edges thanks to them banging around all the time. Thankfully I haven't seen that kind of ingorance displayed here but it's pervasive on another board I frequent.
Pacific Green '96 Contour LX V6
â??98 GTP, light mods, 14.66/94
Calypso Green '92 Mustang LX coupe, 13.56/101
Crown Autocross Club 1999 Street Tire Champion, 2000/2001/2002 Street Modified Champion
KCR SCCA 2002 Solo II Street Modified Champion
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While I agree 100% with your additional information, you'll have to admit that within this context (motorsports, or at least enhancing the performance of a vehicle), NVH is not of concern. No one adds a strut bar in an effort to quiet down their car. People don't have roll cages in Buick Regals to make the things even smoother. This is the suspension forum, where people are looking for performance improvements. I'm keeping the focus there. You probably noticed I always referred to racecars as having roll cages for stiffening... where we all know the cage's principal purpose is driver safety. You did reinforce my point that the front strut bar should be the last mod, performance-wise. And I'll concede that it does look good. The main reason most people have it.
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No, you're right, nobody adds an STB to "quiet down the car", they often add them to get a magical performance increase because so many people believe in the generally overstated amount of movement that exists for them to correct in the first place. So while this is indeed a suspension forum I thought I would add that minor correction because corrections are suspension-related too 
Pacific Green '96 Contour LX V6
â??98 GTP, light mods, 14.66/94
Calypso Green '92 Mustang LX coupe, 13.56/101
Crown Autocross Club 1999 Street Tire Champion, 2000/2001/2002 Street Modified Champion
KCR SCCA 2002 Solo II Street Modified Champion
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And it's very much appreciated. More info is better, I like to see that I'm not the only one "on a mission" to spread knowledge.
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So what do you guys think about a rear STB? Do they make much of a difference?
1998 T-Red CSVT
#3710/6535
Born on 9/23/97
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Again, it's not at the top of the list, but it certainly serves a better purpose than the front one.
When I braced the rear of my SVT, I felt a slight improvement in stability from the rear end. BUT you have to consider the suspension I was running... a full race LEDA coilover setup. On anything softer the benefits wouldn't be as noticeable.
It did help a lot with reducing creaks and rattles back there, especially when driving diagonal over speed bumps or coming into a driveway... proof of it's action in making things more solid.
Again, other things do come first.
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