Body stiffening braces- sorting the good from the crap

[TERRA Operative]

No worries, I'll have a look around.

[Mr Revhead]

it would want to be pretty strong if you intend to use it as a harness bar.

[Sam_Q]

yeah good point I would use 1.25 x 0.095 (32 x 2.4mm) for the horizonal section

[MWP]

I dont think there is much point in rear braces on live-axle suspensioned cars.
The rear strut towers dont see anywhere near the same kinds of forces (twisting, pushing/pulling) that the front towers do in a macpherson strut suspension.

I can see more need for rear strut bracing on cars with IRS though.

Still... can never hurt to add more strength i guess.

[Sam_Q]

hey guys heres one we didnt talk about: what about the brace thats meant to stop firewall flex, more specificly the flex around the brake peddle and the "cusco brake master brace". Does this actually do anything?

[30psi 4agte]

The brake master braces do have some merrit. It depends on the car though as different cars have different firewall designs and hence some can really use this sort of brace and others it makes no real difference.

Cars like the datto 1600 and my cortina can get some real benefits from this as the firewall design is as old as it gets and flex is plentiful.(just like the rest of the car )

Another brace not yet talked about but is useful on these cars and possibly the older corollas is a steering box brace, Which braces the box to the tower to stop the box trying to move away under load.

[cptsideways]

A LOT of aftermarket ones are simply pants from an engineering point of view, take the op one, the strut towers effectively flex in & out along a radius, that bar has pivot points at the exact point you'd want it to be stiff = crap. Also the top strut braces are drilled & these are what take the strain. A simple horizontal bar would work better, a triple brace solid one even better.

My old Mazda 323 GTR had a factory one, it snapped on a trackday once so they do do something

[Sam_Q]

4agte: what about on an ae86? would they have much firewall flex? I am thinking of making something for my car.

cptsideways: snapped a strut brace??? thats a new one.

[TurboRA28]

I think you'd find a lot of firewall flex.. Have someone sit in the car and get on the brake hard, watch the master cylinder and firewall area. You'll see it move.

[Alex]

The rear strut towers dont see anywhere near the same kinds of forces (twisting, pushing/pulling) that the front towers do in a macpherson strut suspension.

Unless of course it's a mid mount, like an MR2

[CrUZida]

Do these do anything?

[Mr Revhead]

they hurt my eyes......


they run right along a rather strong section of the car (just under the seat)
they are bent.

have a read of the thread, and think about how forces twist/bent things.
see if you can work it out

[YLD-16L]

I think you'd find a lot of firewall flex..

My KE25 has a lot of firewall flex, even with the factory fitted brace from the firewall to the strut tower.

Pushing the brake pedal you can see the whole steering column move a little. I'm sure some more bracing to stiffen the firewall would improve the pedal feel.

[Billzilla]

Do these do anything?

They lighten your wallet, that's all.

[Vios-GT_07]

^^
i got them... they didn't seem to do much, thought someone mentioned they do...

anyway i don't really care if it does or not now as it wasn't that expensive and makes a nice place for the harness..