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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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.
