So, my understanding is that modern cars like the MINI are engineered to collapse in precise way during a frontal impact. Chassis, engine and body connections are engineered to fail in such a way as to protect the passenger compartment as much as possible. It seems like these aftermarket lower stress bars could obstruct these engineered crash dynamics and create a serious safety issue.

Can anyone knowledgeable on the topic comment?

 

What's a lower stress bar? Does it involve therapy?

 

Good one... Multiple aftermarket vendors have these out there. It basically ties together suspension subframes and engine up front to stiffen the front end. My question is whether it compromises safety. My gut says yes, but my gut is pretty ignorant.

 

This is a good question.
I wonder if the Mini-Madness (Mason Eng) trapazoid brace that ties to the front is safer than the TSW X-Brace that ties to the rear. I am thinking that the Mini-Madness brace might still let the engine drop down but the X-Brace might block the engine from dropping down.

 

While I definitely like the idea of a stiffer chassis, I also like the idea of not dying. Call me crazy.

 

I think some of those bars are recommend for 'off-road' applications only, perhaps to avoid any litigation from what you are describing.

 

Interesting. Originally I was going to say a couple of pieces of chromoly arent enough to really change things but I thought better of it when I considered it is at least strong enough to stiffen the chassis during cornering.

Naturally the forces associated with say a fontal impact are going to be far greater than anythings seen in cornering. Given the way that some of the braces are attached (ei: the tsw x-brace is anchor to the sheet metal) I would suspect that in a crash either the bolts holding the brace on would shear, the sheet metal would give in some fashion or the frame would simply bend.

There is probably (actually almost certainly) a degree of over engineering that goes into crash dynamics. My statics professor actually deducts points from you if you use more than three or 4 significant figures simply because in most cases in the real world you wont know things more exactly than that anyway. However a crash lab with a known testing methodology that the engineers who design the car might take advantage of that to help boost crash rating while cutting costs, I know I would.

When it comes down to it the only way to know for sure is get the engineering analysis that was done on the car in stock form and see how the brace changes it or bolt the brace on and crash a car into something.

 

Good thread. I don't know about the others but the TSW Brace would have limited if any interference with the safety "break-aways" on the MINI.

If you look at the arm sticking up on this front control arm bushing bracket you will see that "line" cut into it near the bolt hole. That line is the break away spot to help allow the motor and trans fall to the ground during a front impact. While the front of the TSW Xbrace shares that same bolt I won't worry about it (brace) getting in the way. Just my 2 cents.

 

Thanks. That is somewhat reassuring on the TSW brace, but it would be cool to hear some hard facts from the actual engineers/vendors.

 

Good point about the control arm breaking away so the brace should also break away. The TSW X-Brace and Mini-Madness (Mason Eng) Brace both mount to the control arm. I believe the OMP brace also mounts to the control arm.

 

since the parts for "Off Road/Racing Only" parts I don't think you will hear from the engineers. The above post was just my op-ed

I don't know that the XBrace would break away, but it shouldn't stop the above OEM part from breaking away.

 

Good point, I was thinking about it wrong. The X-Brace is bolted to the control arm bolt and the bolt will stay attached to the vehicle. In a crash the control arm will break away and the bolt with the X-Brace may stay in place since the X-Brace goes towards the rear.

That makes me think that the Mini-Madness (Mason & IE) braces that locate towards the front could be an obstacle for the engine dropping down. The control arm will break-away but the brace may remain to hold up the engine.

 

Hmm...

 

Yes, they all allow more energy to be transmitted to the passenger compartment rather than around it. Crash energy transmitted to the passenger compartment = possibly more injuries.
It's the chance you take.

 

Place I go to after work.

 

One thing that comes to mind for me is that the stress bars, I think, are designed to stiffen in torsion. I would think that frontal impacts would be about bending and not torsion.

 

Nice.

- andrew from RCE