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2006 speed6 owner looking for resonably priced front tower brace. Any advice? Anyone selling a used piece in good shape? ;)

2006 speed6
Black On.
CPE Intake
CPE Downpipe

Planned - CPE motor mount / cat back /CPE Flash kit when available
 

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tanabe sells one.

just fyi, our car does not have struts so the bar is useless in terms of suspension upgrading. all it will do is make your engine bay look pretty.
 

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Yummy...double wish bones.
 

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I guess all the GT and GTP cars with cross bracing under the hood wasted their time because they don't have struts. Even my old '67 Mustang had shock tower braces.
A strut tower brace doesn't brace only struts, it braces the force applied to the tower by the springs. A strut tower brace is good for any car, struts or not.
 

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while a tower bar may add rigidity to the frame in the double wishbone suspension, it does not help suspension dynamics. in a macpherson setup, the wheel is located by the strut, so the camber change during cornering is affected by flex in the strut tower. in a double wishbone, the 2 wishbones locate the wheel while the coilover controls the vertical motion. the camber is not affected by flex in the tower. thus, whether you add a tower bar, reinforce the firewall, get a lower tie bar, or stick a 2x4 across the engine bay, they will only stiffen the chassis and not aid the suspension.
 

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while a tower bar may add rigidity to the frame in the double wishbone suspension, it does not help suspension dynamics. in a macpherson setup, the wheel is located by the strut, so the camber change during cornering is affected by flex in the strut tower. in a double wishbone, the 2 wishbones locate the wheel while the coilover controls the vertical motion. the camber is not affected by flex in the tower. thus, whether you add a tower bar, reinforce the firewall, get a lower tie bar, or stick a 2x4 across the engine bay, they will only stiffen the chassis and not aid the suspension.
[/b]
Plus our towers are right at the firewall unlike some other cars where it is closer to the middle of the engine bay - that also reduce flexing.
 

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while a tower bar may add rigidity to the frame in the double wishbone suspension, it does not help suspension dynamics. in a macpherson setup, the wheel is located by the strut, so the camber change during cornering is affected by flex in the strut tower. in a double wishbone, the 2 wishbones locate the wheel while the coilover controls the vertical motion. the camber is not affected by flex in the tower. thus, whether you add a tower bar, reinforce the firewall, get a lower tie bar, or stick a 2x4 across the engine bay, they will only stiffen the chassis and not aid the suspension.
[/b]
I cannot disagree more, I just could not take another mindless bashing of the strut tower bar as not being a performance mod. Flex in the chassis has negative affects on all aspects of cornering, braking, and acceleration. Maintaining the relative position of the suspension pickup points controls alignment geometry regardless of strut or coil over, it therefore affects camber, cross camber, toe, total toe, caster, weight transfer, etc and to make it worse the flex and therefore the effect is constantly changing. Every stiffly sprung car, especially a heavy car, can benefit from this mod.

The first noticeable improvement with a well designed strut bar is that initial movement in the steering wheel makes an instant change in car direction, instead of the chassis flexing first the car just changes direction. It's best to install the bar and drive the car for quite awhile (if you don't have low profile tires and a stiff suspension the effect will not be very noticeable, this should not be a problem with our cars). Then take the bar off and go for a drive, if you are sensitive to changes in tire pressure or alignment settings you will be amazed at the differnece a good strut bar makes. If you have never done this experiment on a stiff setup car or if you are not used to pushing a car to 9/10+ then you may never notice the improvement that a strut bar makes. This mod will not guarantee a faster lap time on a track, but if you push the car hard it will reward you with a more predictable car under cornering, especially during braking and acceleration. For an aggressive driver, it helps you push the car to the limit with confidence.

Nevermind my rant, I'm just a MS6 newb that's bored with the Rx7 forums. Too many newbs and wannabe's on that forum questioning race proven principles and sound engineering, I see the behavior is prevalent here as well.
 

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The upper A-arm mounts are still mounted to the strut tower, about 8" from the top, so the camber will still change with the tower flex. You are saying that the chassis stiffening that Mazda did on the Speed6 was a waste of time, as you clearly state that a stiffer chassis does not help the handling. Uhhh...wrong. Chassis flex=bad. Seriously, I understand that the brace will not do much on a Speed6, but it's still all good.

BTW In my opinion, having a stiff chassis is one of the MOST important things you can do for your suspension. I'll use the Jeff Gordon "T-Rex" car as an example. As far as I know, this is the only rule-compliant car ever banned ( NASCAR did not rule the car as illegal, the team was just asked not to bring it back ) from racing because the computer designed chassis was too "advanced" ( stiff ) and was seen as an unfair advantage. Maybe they should have just used a 2x4...hmmm?

Sorry, twokrx7. I was writing this at the same time as you were.
 

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double wishbone



now here's some more illustrations:

http://www.autozine.org/technical_school/h....htm#Sus-design

notice how the shock and spring assembly is not even mentioned in the camber analysis. why you ask? because it is the dual A-arms in the double wishbone that locate the wheel.

now see how it's all connected:



the 4 bar linkage below controls the horizontal motion while the shock and spring assembly transmit the vertical forces to the top of the tower. flex in the tower will be in the vertical plane. camber wont change.

now let's go to the macpherson:






see F3 here? well F3 is what needs to be controlled by a strut tower bar. if there is flex in the tower, then the camber will be affected because it is the strut assembly that is locating the wheel.
 

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In a dual A arm suspension the upper A arm is connected to the shock tower. The spring and shock is also connected to the strut tower so any movement in the tower will affect the shock and spring performance, so the corner weights are affected. This is especially noticeable during initial turn in, any quick transition such as flicking the car thru a quick left right left s on a track, etc
 

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In a dual A arm suspension the upper A arm is connected to the shock tower. The spring and shock is also connected to the strut tower so any movement in the tower will affect the shock and spring performance, so the corner weights are affected. This is especially noticeable during initial turn in, any quick transition such as flicking the car thru a quick left right left s on a track, etc
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Just thought I'd revive this thread since this sub-forum is kinda dead.

Anybody else want to chime in on this topic?

From Autoexe's website:

Strut Tower Bar ~$250
It is a welded one-piece type with cylindrical rib that binds together the upper sections of the right and the left suspensions tightly with the strong steel pipe and plate. It reduces the distortion of the body applied from the suspension to ensure the movement of the suspension. As a result, it creates a zippy feeling of driving a car. All the more because it is part of the basic item, we stick to the function-oriented stance.
<end>

...and who wouldn't want the "zippy feeling of driving a car" too?
 

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I'm interested in one myself...anyone have a link? I've seen reference to Autoexe's site, but I can't seem to locate that.

I've seen the brace in the pics of ryceboi's MS6 with the TMIC upgrade, and it looks nice.

Thanks guys!

:)
 

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The reason this mod won't net you anything in the Mazda6 is because Mazda already beat you to it



Notice right behind the strut towers there is a large crossmember. This crossmember is welded to the towers and welded to the firewall -- in effect turning your entire firewall into a strut tower. You can pop open your head and take a look at it yourself. There's a strut bar there already, it's just hidden slightly amongst the crap on the firewall and it's moved to right behind the tower from right on top so that it's not obstructing access to the tower.

There's no way a piece of 1" steel screwed onto the towers most of which even have hinges :sarc: is as fractionally as effective as that welded crossbeam plus the firewall is at stopping chassis flex. Any benefit would be infintessimal.

Which is precisely why, after all the time and money Mazda spent on making the MS6's chassis rigid even going so far as to take the major hit of removing rear-seat fold down, it didn't add a $10 piece of metal across the front towers. Because it's not necessary.
 

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Try japanparts.com, they have all the stuff from autoex (as he drools over the coilover setup)
Also Corksport has it listed on their site. In fact they are manufacturing one themselves for alot less than the Autoexe pc. Theres isn't red, so it won't have the hp gains. :D
I would list this mod in the appearence category, but I will probably get one once all the go fast parts are on, I think it looks great and certaintly can't hurt.
 

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Which is precisely why, after all the time and money Mazda spent on making the MS6's chassis rigid even going so far as to take the major hit of removing rear-seat fold down, it didn't add a $10 piece of metal across the front towers. Because it's not necessary. [/b]
Officially the rear seats don't fold down, but they actually do.
 

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I just looked up the Autoexe piece, and it's nice...but $250ish for a piece of powdercoated steel tubing? That seems a bit steep IMO. I have a strut tower brace here for my Mustang, and it's a much larger piece with three sides, and it was like $100.

*shrug*
 

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