X/H/Ladder Brace

[herrods]

It comes in many different names, (as the title suggests)

 

Im talking about the brace one may put under their car to improve rigidity, bolted to the chassis rails @ the firewall and close to the diff, made of tube steel.

 

First of all, Has anyone ever seen one of these for a Z, and if so, where can one buy one.

If there is a lack of product, I intend to make one, and one for anyone who also wants one @ the same time.

 

Before I delve into the making process, any siggestions on optimum material for max rigitity, without the cost of something stupidly heavy.

I was thinking the same tube steel as  4WD rock sliders are made of, which is about 40mm outer diameter, 2mm thick mild steel tubing,

 

The reason for this creation is because I have found a small crack in the chassis rail at the point where the firewall completes its curve, turning into the floor pan...

 

anyone shed some light on this/have an opinion?

 

Cheers

Dave

[Whittie]

Hi Dave,

 

Considering your location a trip to Stuart Wilkins would be worth a shot. When I was there he showed me one that he makes for zeds. It's made out of square tube and fits exactly where you mention. It crosses the car under the gearbox and did some funny things to seal against the bellhousing where the gearbox sticks below the bottom of the motor with some plastic mounting face. He also designed it so it doesn't hange below the car to get ripped off/bend the chassis!

 

I think he quoted me around $200 for one, but that could be off/have changed (ie, be more like $400. It was enough for me to think about making one instead of buying anyways, but not by much).

 

I will likely be building one for my car as part of my build and will probably just use square tube as well given it's low cost. The part is not really large enough for differant material types to impact too much on the weight of the brace.

[Roberto]

Hi Dave,

 

In the US, there is a mob selling these below.  Not cheap ($700) and even more expensive to get it here, but you can see what he has done in the pic.

 

The site is:

 

http://www.datsunstore.com/product_info.php/products_id/661?osCsid=49b110cd9f3d03035efe85768de69115

 

Doesn't look like what you are describing, but that may give you some ideas for bracing.

[Roberto]

Sorry, I posted my last message without the pic attched:

 

[RB30X]

How much more rigidity would that add do you think?

 

While you are on the subject, what about those braces that sit underneath the front guards/fenders that brace the strut tower against the cabin of the car. Are those sorts of braces available?

[Roberto]

I have never seen a fender brace the goes under the fenders.  I can't really imagine it. 

 

I have seen this one that braces the fenders and strut towers through the engine bay.

 

[herrods]

That brace from the US doesnt look like it would do a whole lot, except add another layer of metal to the already existing chassis rails.

 

Whittie,  I have started to do some digging for current prices etc with stuart wilkins, but given the fact that my engine and gearbox are not standard, it may become a bit of an issue getting one that is such a snug fit to where the original gearbox etc fits in.

 

That being said, the point you raised about not being ripped off or bending the chassis should it come in contact with something on the road surface is a good one.

 

It could be somewhat difficult in my position to achieve this though, because my 3" straight through exhaust is the lowest point under the car, and so any chassis bracing would have to go underneatht hat,m lowering the lowest point by the width of the tube.

 

so:

- If the brace was made from a flat plate like the one from america, do you gain nany rigidity, or just another piece of metal?

- If the brace was made from tubing, and then flattened to give maximum ground clearance as it passes under the exhaust (think stepping on a garden hose)  would it lose strength,

- If a brace was made in the shape of a perfect X, and mounted under the rear of the motor and the gearbox, but not extending the rest of the way down the chassis rails, would the car then suffer from a case of transfer of stress, where the  twisting etc is simply transferred to the unbraced section?

 

Apart from that, I will wait to hear back from SW motorsport.

 

In answer to you question Rb30x, I have never seen a brace like what you are talking about either.  One i intend to make for myself though is a modification on teh strut braced posted earlier.  If you jump onto the google image search, and look for the front storage on an MR2, the original strut brace is the idea I had in mind.  This is because there is about half of a bee's member's worth of clearance in my engine bay with the hood shut.

[RB30X]

Ben has some good pics in his build.

 

http://www.viczcar.com/forum/index.php/topic,2043.0.html