Chase, when you say solid, are you saying a solid bar or just solidly mounted (no hinges)

A completely solid bar seems like it would be obscenely heavy.

I just got home and settled in, hopped online and got so excited reading all these great responses so far. I'll be able to get back to everyone tomorrow, but I just wanted to clarify my poor wording quick:

My post says "welded solid," when I should have just said "welded." A solid bar WOULD be obscenely heavy, and none of us want to add any more weight to this car! And at a certain thickness the bar is no longer the limiting factor, the chassis will be. For the record the bar we used on the prototype to test deflection was 14ga, and we'll test more once we settle on brackets, etc.

Chase

I really like the simplicity of it. Definitely looks OEM but I could also see something with the triangulation bars integrated somehow. I'm not one who needs red/blue crap in the engine bay. But what about a "bare metal" or "primered" option so folks can go get them powdered whatever color they want? (Primered just to keep rust off...any PC'er will blast the parts anyway).

I'll let the more smarter people overrule me here, but I've heard a few times that if a strut bar isn't really beefy, it's almost useless. If it's going to function it needs to be strong, not a flat piece of aluminum.

Visually, I'm not sure about the mounts, only because I don't know how strong those mounting points are, like someone mentioned above, vs. the strut studs. Maybe it's fine and I'm just used to seeing a common mounting style.

Lastly, and this isn't an issue for me (at least not any time soon), but I'm sure some out there will want to make sure it fits with X/Y/Z turbo or SC kit or catch can, etc.

Great job so far, can't wait to see where this goes!

I would hope it will be made from aluminium because I don't want to add any unnecessary weight to my car. Surely alloy construction can match steel in function with less weight?
If that's correct and the OEM bars are steel then a set of 3 in black alloy to look OEM would be my choice.
Perhaps an option to have them in polished alloy but with a bit more attention to form to go with the bling factor.

I agree, the attachment needs to be more robust. The thickness of the steel on the end of the bar is not enough. Also, I think a flat rectangular solid bar would do more than a hollow round one. Weight is really not much of an issue for what this part does. If you make slots for the attachment points, you can get a preload adjustment by jacking the car and then tightening the mounting bolts. Here is a picture of my favorite strut tower brace design (from StrongStrut.com). Also, read the "Strut Brace Facts" at http://www.strongstrut.com for their designers strong opinions.

I think you will find that a straight hollow round tube will be much more rigid than a curved solid bar of the same weight.

I'm sure Chase will address a lot of the comments in more detail tomorrow, but I wanted to chime in to thank you all again for your input so far! Without you guys, we would have a tough time molding these into such successful products!

Regarding the engineering side of things, we've adopted a methodology for this particular product and it's to keep the brace as clean, simple and affordable as possible without sacrificing performance. We've got the tools and the knowledge to collect and analyze real, robust data and react accordingly. If a bracket is too thin to be rigid enough, or if a lighter bar will do the job as well as a heavier bar, you can bet that our engineering and design process will bring those details to the surface so that we can all benefit from them.

So, with that said, keep the ideas flowing! Hopefully you guys can teach us a thing or two and maybe we can do the same. In the end, we'll all end up with a killer strut bar (and maybe triangulation bars, if we can prove that there's improvement to be made, sorry Chase ;))!

Matt
Engineering

Summarizing: For a given amount of chassis flex (however much there is), your simulations suggest that the two factory bars decrease strut tower deflection by ~50%. Adding the Grimmspeed bar would decrease tower deflection by ~90%.

Questions:
1) Tell us about your model. FEA can be a mixed bag, and it all depends on how you set things up. Be proud of your hard work, and show it off!

2) How much strut tower deflection have you guys seen during testing?

RCE recorded 4-5 mm of deflection on the 2004 STI in a 1g skidpad session, per this discussion: LINK

The FEA results are directly proportional to the chassis stiffness you chose, so that's why I'm curious about it.

Alot of methods have been discussed over the years, without enough actual results.
Deflection: RCE's draw a mark method (kinda ghetto). Linear potentiometer (can be noisy).
Stress: Shear pins in a strut brace (only tells max compression force). Strain gages on a strut brace (can be noisy).

While I appreciate the "stiffer is always better" argument, if we can identify a legitimate deficiency and address it properly... your products will fly off the shelf.

Certainly interested in this. I'm no expert in this arena, so I'll leave that to you guys and those who can provide meaniful input. I will say I do like the simplistic approach that will lead to a product that works rather than just looks good!

Sub'd to follow along and watch the updates!

Awesome insight! I'll save some of these details for the morning, since it's getting late and I'm not at a workstation, but I should mention that we haven't shared any FEA yet. The model shown in the second figure is actual, recorded data from a stationary vehicle. FEA and simulations are great, and you'll definitely see a decent amount of it, but we really value good, hard data collection when possible. Hopefully we can stop just short of making me dust off my WinGeo discs.

We will definitely be refining our test methods as the project progresses and we can justify the investment. We just wanted something, even if it's rough, to justify starting the project. Between the two of us, we have a good deal of experience with FSAE, SAE Baja, racing and vehicle dynamics testing/evaluation, so if we can justify the time/resources, you can bet we'll get way too far into the data/analysis. Stick around, you're obviously a sharp dude!

Hopefully once this 8-12in of snow they're predicting for tomorrow passes, we can get back to warm, dry roads and the, uh, testing.

Matt
Engineering

Make it like this and I'll buy it without question.

It looks like the trd strut bar

I liked

Even if our testing shows that the extra two mounting points don't add any performance, just cost? I'm not saying that's the case, just trying to get a feel for everyone's priorities! Appreciate the input/support! Keep it coming!

Matt
Engineering

I like the original. I doubt I would be buying one though, just for the simple fact that I don't think I can modify these in order to stay in my current autoX class.