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Total overkill..... but I like it! Nice fab skills!
 

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Don't the heim joints/rod ends defeat the whole purpose of an export brace? The shock towers can still move.
 

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You will definitely need a Monte Carlo Bar. THe heim joines add a couple of degrees of unwelcome freedom. I know a lot of people design with tehm but it makes no sense unless you are trying to move metal to expand or contract using the rods and threads kinda like orthodontics. Otherwise I would think you want the stiffness of the original brace not added movable joints IMHO. THat said, very nicework here...
 

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Don't the heim joints/rod ends defeat the whole purpose of an export brace? The shock towers can still move.
The back of the shock tower is triangulated with the cowl/firewall and inner fender, so movement is somewhat restricted. The front of the shock tower may want to move and given the back is constrained, the result will be a twisting action. The twisting can be resisted with the addition of a Monte Carlo bar mounted to the front of the shock tower.
 

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Looks nice! However, @dobrostang is right about the unwanted degrees of freedom by using the heim joints. I think this is mostly a problem at the firewall, because it causes a point load at each brace end, thus causing the firewall junction to twist. The one piece export brace has this joint fixing the rotation components (on the vertical and lateral axis') which is much better because it will not twist at the firewall, in those two axis'. I think this setup will not be as stiff as the one piece export brace and could cause the firewall/cowl area to fatigue. The unwanted degree of freedom at the shock tower would be supplemented by a MC bar but that won't help the firewall flex issue.
 

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I am considering changing the firewall joints to a solid non heim joint.
A double shear clevis would help get rid of the bending the cowl flange up and down but will still cause rotation on the axis of the bolts. If I had to have a clevis design, I would do the version with two rods on both sides which would distribute the load into two points instead of one. That's what is great about the "continuous joint" of the one piece brace, it eliminates lots of degrees of freedom.
 

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Looks nice! However, @dobrostang is right about the unwanted degrees of freedom by using the heim joints. I think this is mostly a problem at the firewall, because it causes a point load at each brace end, thus causing the firewall junction to twist. The one piece export brace has this joint fixing the rotation components (on the vertical and lateral axis') which is much better because it will not twist at the firewall, in those two axis'. I think this setup will not be as stiff as the one piece export brace and could cause the firewall/cowl area to fatigue. The unwanted degree of freedom at the shock tower would be supplemented by a MC bar but that won't help the firewall flex issue.
Agreed. The fire wall connection makes for some funky reactions. As it appears in the photos, the shock tower end of the brace connection appears lower than the firewall, thus any force at the shock tower would twist the mounting plate slightly up at the firewall, but... the connection at the firewall is a cantilever off the bottom of the bracket which would want to twist the plate down. Without specific measurements it's hard to say which twisting motion would be greater.
 

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A double shear clevis would help get rid of the bending the cowl flange up and down but will still cause rotation on the axis of the bolts. If I had to have a clevis design, I would do the version with two rods on both sides which would distribute the load into two points instead of one. That's what is great about the "continuous joint" of the one piece brace, it eliminates lots of degrees of freedom.
Often simpler is better. Given the export brace rarely needs to be removed, I like the moment resistance an original export brace provides. The braces I have seen with dual bars generally have some triangulation to them so that they also create some moment restriction at the firewall.
 
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Discussion Starter #12
I also may add an angle iron lower bracket welded to the firewall that connects the 2 bolts.
 

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I am considering changing the firewall joints to a solid non heim joint or adding an angle iron piece to the bottom.
Replace OR with AND and I think you are on to something. Here is how I did mine: Custom Export Brace Build it in with the MOnte Carlo bar kept them two peices. I want no relative movement between shock towers and cowl. The system is fabricated to hold one shape, no movement anywhere. Can't figure a good reason to have any "joints". I also added the angle iron upside down under the flange to the firewall. I used 3 bolts (same size as original export brace bolts and threaded plate inside the interior to clamp the firewall with some serious torque. You want it all to operate as one piece of solid framework...
 
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