Driving Impressions: Lower Stress Bar

[Kirk]

GREAT news!!! I finally got in the 3rd iteration of lower stress bars and the parts look really fantastic. I got them test fitted to the car and they go on just fine – very easy install.

Here are some pictures to compare the new parts to the old parts from the 2nd iteration I did. The main bar is 3/4" steel tubing with very heavy duty heim joints. The steel heim joint for the main bar is the one to the far left in the picture comparing the heim joints. This heim joint is rated to handle over 9,000 lbs in static load, more than enough for the application. The main bar in the photos is unfinished steel because this was a one-off prototype/sample I had made. The regular bars will still be custom made to my specs, but I will have them yellow zinc chromate plated for corrosion resistance. This is a very good, strong bar, much better than the aluminum main bar I had used for my 1st and 2nd iterations.

The biggest change is with the side bars. After some careful measurements I determined that I could use a spacer to step up to a much larger bar. As you can see in the pictures comparing the side bars from the 2nd to 3rd iterations that there is a significant change in the robustness of the bar and heim joint. The new side bar heim joint is the one in the middle of the comparison picture while the 2nd iteration (red) is on the far right. The new heim joint and bar for the side bars are still aluminum, but this more robust heim joint is rated for almost double the static tensile strength at almost 8,000 lbs – again more than sufficient for the application. You’ll notice that to achieve this, the shank (threaded portion) of the heim joint is larger than the red, 2nd iteration piece. The main bar heim joint has an even larger shank than the side bars. To get the side bars to fit I used a special conical spacer (pictured) that goes perfectly with this heim joint.

Again, I’m absolutely tickled with these parts. I made some home-made bars at first and then switched to some aluminum parts. These 2nd iteration aluminum parts were okay, but I wanted to get something still better and stronger. This latest iteration is pretty much spot on what I wanted to achieve. Robust, strong, and a cinch to install.

So, now that I’m satisfied that I’ve taken this as far as I can I’m officially moving ahead with the group buy. Details will be posted in the Classified section of this board.

Kirk

[Kirk]

Here are a few more photos of the lower stress bars.

Kirk

[Franco]

Hi Guys, Love The Passion

Take Care

[Bobiam]

Good work Kirk........

They look pricy, but very well made. The "Porsche" of stress bars!!!! Will be interested to see the pricing when available.

You should sell they to Porsche!

Bob

[Kirk]

Originally Posted by Bobiam

Good work Kirk........

They look pricy, but very well made. The "Porsche" of stress bars!!!! Will be interested to see the pricing when available.

You should sell they to Porsche!

Bob

Pricing is now up in the Classified section of this website:

Lower Stress Bar Group Buy

They may look pricey, but they're not. I don't believe that just because it's a "Porsche" that you should get raped on the cost! Quality and strength though are way overkill for the application, so they're not "cheap" even though low cost.

[Bobiam]

Kirk... That pricing is VERY fair for a well developed and adjustible product. Quite substantial compared to the original design.

[roadracer311]

I just wanted to chime in and give my feedback on this subject now that I've had my Technobrace (from Pedro) installed for about a week.

It solved both of the problems that I was hoping it would solve. Ever since I bought my 2003 Boxster S, I've loved the handling, but have been bothered by the feeling that it would suddenly oversteer when cornering over bumps. I mostly noticed this on concrete-slab-type off ramps. The other thing that my car used to do was shudder a lot when going over bumps. I'm happy to report that both of these problems are now solved.

One side effect is that it feels like there is more feedback coming through from everywhere. It feels like I added 5 lbs more pressure to the tires. The good news is that I've been running them a little high anyway, so now I'm planning to take the pressures down closer to the recommended pressures to see if it smoothes the ride out a little.

My background: I have a fairly sesitive seat of the pants reaction to things. I raced motorcycles for 5.5 years. I also have a degree in physics, for what that's worth.