Driving Impressions: Lower Stress Bar

[Bobiam]

Well, I made and insrtalled my LowerStress Bar today. Used alum 7/8" hex stock and correct sized metric automotive grade bolts/nuts. Hex made it easy with built in flats. Had to unbolt one sway bar mount to slide the bar in (probably since the hex stock is 1" dia. point to point).

24" bar, 22 1/4" between the holes. 3/8" drill will work with a minor tuning with a round file (if the better fitting metric bolts are used).

At 38 degrees here in CT I can't take it very hard on corners to test this thing without the summer tires sliding. Do, I'll go on faith that the bar helps as allof you say it does. Total price with materials from on-line vendors around $33. Rather pay shipping than waste gasoline (and my time while searching)!

Bob

[HB.]

Now that I have the front and middle upper bar installed, I will be looking into adding this mod in the next couple weeks. I'm still curious as to how the 2 shorter bars will help chassis flex? Can someone explain how they make an improvement, I'm always up to learning something new :dance:

[Bobiam]

Originally Posted by HB.

Now that I have the front and middle upper bar installed, I will be looking into adding this mod in the next couple weeks. I'm still curious as to how the 2 shorter bars will help chassis flex? Can someone explain how they make an improvement, I'm always up to learning something new :dance:

I have doubts that the 2 extra bars mean much. If you look at the rear of that alum plate where it is bolted in, that's a fairly light duty drop section of framing. It can't possibly be designed to do much in the way of providing controls of stresses regardless of what framing you attach to it. That triangular shape of the plate is likely to prevent a twisting motion but I doubt it has much work to do. I'll call 'em "Can't Hurt Bars"!!! Just one guy's opinion.

[Kirk]

Originally Posted by Bobiam

I have doubts that the 2 extra bars mean much. If you look at the rear of that alum plate where it is bolted in, that's a fairly light duty drop section of framing. It can't possibly be designed to do much in the way of providing controls of stresses regardless of what framing you attach to it. That triangular shape of the plate is likely to prevent a twisting motion but I doubt it has much work to do. I'll call 'em "Can't Hurt Bars"!!! Just one guy's opinion.

Yeah, the lower side bars certainly can't hurt. They're something simple to install (easier to install than the main bar) that can further reinforce the stress plate.

As for the drop section of framing in the very back, it was loose and almost falling off on my car when I bought it used. I assume the mounting bolts just vibrated loose. When I tightened it up (this is before I installed stress bars) I immediately noticed a difference in cornering in the car. So I do think it does something in tying the back of the stress plate down solid, and like you said, probably preventing some twist. I think that adding the side bars and triangulating the whole thing certainly would help with this function.

[Kirk]

Well I FINALLY found a place that can manufacture the different components that I want to make a really decent lower stress bar system. I just ordered one set of parts. I should then have an update and some photos sometime next week with the new parts.

What I’m putting together is a main bar that’s 3/4" steel tube. I can source stainless steel (at 3X the cost though) for the main tube, but for now I’m going with yellow zinc plated steel. Attached at each end will be some heavy duty steel rod ends. These are rod ends that are beefier than the standard 3/8” items. They’ve got a larger threaded shank so they can be used with the large steel rod. These aren’t racing rod ends since they don’t really need to move much. Instead I’ve focused on getting nice strong and well constructed rod ends for the main bar. This should be a pretty heavy duty setup that will still allow adjustability for ease of installation.

The secondary side bars are going to look just like what I posted photos of recently. The exception is that I’ve figured I can go with one size larger rod end. That also allows me to go to a larger diameter rod. In addition I’ve switched to a different brand of aluminum rod ends that are more robust with a larger shank, like the steel rod ends used in the main bar. They’re silver though, not the pretty red I showed before. The static tensile strength of these rod ends is almost double that of the ones I’ve got on my car now.

More to come next week… photos and install notes.

Kirk

[blue2000s]

Originally Posted by Kirk

Well I FINALLY found a place that can manufacture the different components that I want to make a really decent lower stress bar system. I just ordered one set of parts. I should then have an update and some photos sometime next week with the new parts.

What I’m putting together is a main bar that’s 3/4" steel tube. I can source stainless steel (at 3X the cost though) for the main tube, but for now I’m going with yellow zinc plated steel. Attached at each end will be some heavy duty steel rod ends. These are rod ends that are beefier than the standard 3/8” items. They’ve got a larger threaded shank so they can be used with the large steel rod. These aren’t racing rod ends since they don’t really need to move much. Instead I’ve focused on getting nice strong and well constructed rod ends for the main bar. This should be a pretty heavy duty setup that will still allow adjustability for ease of installation.

The secondary side bars are going to look just like what I posted photos of recently. The exception is that I’ve figured I can go with one size larger rod end. That also allows me to go to a larger diameter rod. In addition I’ve switched to a different brand of aluminum rod ends that are more robust with a larger shank, like the steel rod ends used in the main bar. They’re silver though, not the pretty red I showed before. The static tensile strength of these rod ends is almost double that of the ones I’ve got on my car now.

More to come next week… photos and install notes.

Kirk

Kirk-

I agree with your first assessment of the bars. If you've still got the original plate in place, it will absorb most of the tension in the suspension movement. The bars themselves will be mostly in compression (as the ball ends don't resist moments) so the aluminum bars are more than enough in your application.

[Kirk]

I noticed over at PPBB that Pedro is now selling a fixed, solid bar for $70 plus shipping, which is what MartinJ is referring to. The original $130 Mantis bar was adjustable though to allow easy fitment on any car. The Pedro bars do vary by 3 mm depending on whether they're for a 986 or 987, but otherwise are just a solid aluminum bar with holes drilled in the ends.

I think it’s great that Pedro is willing to give a lower cost option to those people who don’t have the skills or time to fabricate their own bars. But it’s precisely those people who need an adjustable bar that’s easier to install and will fit any model. Plus I personally think that $70 for something that’s less than $10 in materials is a bit of a stretch.

Given this situation I would be willing to consider setting up a group buy for the adjustable lower stress bar I’m working on now. The main bar, as I described previously, is 3/4" steel tube, zinc plated yellow, with very heavy duty rod ends. It’s adjustable to fit a 986 or 987 (probably Cayman too) and more than strong enough for the application.

I’ve ordered one of these bars for my own car (third iteration) and was just on the phone with the company yesterday. There is some delay because the main bar is custom made to the right length for me and the rod ends are a special order item (larger shank than normal), but I should have the parts and then photos up before Christmas.

If I put in an order to have 20 bars made I can get the price down to $65 plus $10 fixed shipping cost (continental U.S. only) for the main lower stress bar. I’m willing to do this if I can get at least 10 people interested, assuming I can get rid of the other 10 bars on eBay or the likes. Let me know by PM or e-mail at kbristol@lycos.com if interested. If I get enough responses I’ll follow up in January with a formal group buy in the classifieds section of this website.

I’d also be willing to put together something on the aluminum side bars. Again, same specs as I recently posted – a larger diameter bar with heavier duty aluminum rod ends (not the red ones in my photos) and fully adjustable. These are nice, racing rod ends though and thus are a bit pricey. Plus you’ve got two bars and four rod ends to do the side bars. You’d be looking at $95 for both, shipping included with the main bar.

Kirk

[ppbon]

Originally Posted by Kirk

I noticed over at PPBB that Pedro is now selling a fixed, solid bar for $70 plus shipping, which is what MartinJ is referring to. The original $130 Mantis bar was adjustable though to allow easy fitment on any car. The Pedro bars do vary by 3 mm depending on whether they're for a 986 or 987, but otherwise are just a solid aluminum bar with holes drilled in the ends.

I think it’s great that Pedro is willing to give a lower cost option to those people who don’t have the skills or time to fabricate their own bars. But it’s precisely those people who need an adjustable bar that’s easier to install and will fit any model. Plus I personally think that $70 for something that’s less than $10 in materials is a bit of a stretch.

Given this situation I would be willing to consider setting up a group buy for the adjustable lower stress bar I’m working on now. The main bar, as I described previously, is 3/4" steel tube, zinc plated yellow, with very heavy duty rod ends. It’s adjustable to fit a 986 or 987 (probably Cayman too) and more than strong enough for the application.

I’ve ordered one of these bars for my own car (third iteration) and was just on the phone with the company yesterday. There is some delay because the main bar is custom made to the right length for me and the rod ends are a special order item (larger shank than normal), but I should have the parts and then photos up before Christmas.

If I put in an order to have 20 bars made I can get the price down to $65 plus $10 fixed shipping cost (continental U.S. only) for the main lower stress bar. I’m willing to do this if I can get at least 10 people interested, assuming I can get rid of the other 10 bars on eBay or the likes. Let me know by PM or e-mail at kbristol@lycos.com if interested. If I get enough responses I’ll follow up in January with a formal group buy in the classifieds section of this website.

I’d also be willing to put together something on the aluminum side bars. Again, same specs as I recently posted – a larger diameter bar with heavier duty aluminum rod ends (not the red ones in my photos) and fully adjustable. These are nice, racing rod ends though and thus are a bit pricey. Plus you’ve got two bars and four rod ends to do the side bars. You’d be looking at $95 for both, shipping included with the main bar.

Kirk

Kirk:
First of all my Technobrace is not just a bar with holes in the end.
The Brace is carefully machined to fit perfectly on the lower suspension supports.
They are also machined so that the hex bolt's head is secured and therefore tightened without the need of a wrench for the top portion.
It may be $10 in materials (solid 22.2 mm aluminum rod plus two automotive-grade hex bolts) but there's a lot of labor involved as each Brace is handcrafted to assure perfect dimensions and perfect fit.
It is this precisely that makes it much simpler to install than an adjustable brace. There are only two bolts to tighten and that's it.
There's nothing wrong with an adjustable brace, I just decided to simplify my version and make it more affordable to manufacture.
You also talk about a group buy being more affordable. If the group purchases 20 TechnoBraces from me I'll bill them at $59 each.
Happy Boxstering,
Pedro