Under hood brace

[turbovan]

I’ve seen this term used by several aces and even vendors on this sight, but I’ve been unable to find a definitive answer on its definition. Is a underhood brace the factory bars tying the cowl to the fenders? Is it tubular J bars tying the firewall to the front frame rail? Can the same benefits be had utilizing inner fender bracing as pictured below(pic stolen from curleysracecars)? What is it’s purpose?


To clarify, I am not talking about the inner fender bracing offered by uscartool and others.

 

[33IMP]

I think the purpose of the bar in the photo is to strengthen the shock mount for a coil-over shock, or McPherson strut, to replace the torsion bars.
And to me (and I may be completely wrong) the underhood brace is the formed steel construction attached to the bottom side of the hood panel, to give it strength and maintain shape.

 

[ch1ll]

An underhood brace would be one that connects to both shock towers. These are popular in mustangs and I have never seen one on a mopar. On mopars the fender aprons are structural. More bracing can be added like the one you have pictured. Another option is the braces sold by US Car Tool and viewed on their website. The purpose of these braces is to stiffen the front end and greatly improve handling.

 

[Dana67Dart]

A monte carlo bar ties shock tower to shock tower.

 

[Darter6]

Sounds like you may be talking about these in the photo ? On later models of Mopars,this being a 79 B body,also used on F bodies and even late A bodies.
I believe most all Mopars by 1975.
Struts from the cowl to the inner fenders. I assume Chrysler started using them for a reason.
Necessary? Yes, no, Maybe ?

 

[Dana67Dart]

Sounds like you may be talking about these in the photo ? On later models of Mopars, this being a 79 B body, also used on F bodies and even late A bodies.

Unless they reinforced the cowl area, I don't see that bar providing much in the way of strength.

Maybe it was an attempt to build in some structural stability after all the crumple zones got added to the fronts of cars????

 

[33IMP]

View attachment 1715979543
Sounds like you may be talking about these in the photo ? On later models of Mopars,this being a 79 B body,also used on F bodies and even late A bodies.
I believe most all Mopars by 1975.
Struts from the cowl to the inner fenders. I assume Chrysler started using them for a reason.
Necessary? Yes, no, Maybe ?

To me, that's a shock tower brace (montecarlo bar). I'd run one on a handling car, just in the way for a street strip car.
(I had something similar, from the factory, on a cobra jet Ranchero. Made a difficult to work on engine, even harder. Can't say it did dick for handling. )

 

[Dana67Dart]

To me, that's a shock tower brace (montecarlo bar). I'd run one on a handling car, just in the way for a street strip car.

Monte Carlo Bar keeps the Shock / Spring towers from collapsing inward on a mustang and other cars with that front suspension design

Blue arrows are basic force vectors on/from the shock/spring tower brace

Red are on/from the Monte Carlo Bar

Green cir is where this design fails, it introduces a flex point so the gains of the MC Bar are lessened

(Don't get all technical on me if I did not get a force vector 100% correct, I have forgotten more of my engineering classes than I remember ever having!)

 

[turbovan]

I’ve read there isn’t much bracing needed to the shock towers unless a coil over conversion is being installed?
I see the under hood brace term being used for chassis stiffness:

Post #10 by BergmanAutoCraft

Can you feel improvement after fitter USCT stage 2

I could dig up quite a few more mentions, but this was the post that made me the most curious.

 

[Cuda Al]

Unless they reinforced the cowl area, I don't see that bar providing much in the way of strength.

Maybe it was an attempt to build in some structural stability after all the crumple zones got added to the fronts of cars????

My 69 Polara has them but the inner fenders are not part of the unibody, the crumple zone control just makes sence.


Alan