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Scot,

Cool. I like the idea of welding that type of brace in for the extra level of rigidity.

I copied your rear frame rail brace many years ago, and at the same time did the Dick Miller triangulation braces. Rear of the car definitely felt tighter and more composed/predictable, especially on the road courses.
It's visible in the attached photo if you can zoom in- underneath the rear tubular bumper.

Side question, could one do a similar front brace as that rear frame rail brace, same idea, bent or straight tube hammered into place and welded? Or is the front of the car just too crowded and/or compromises future serviceability to that area?
52DB0DA2-EA6C-42EA-B448-0BE3BAB511E2.jpg
 

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This thanks to gbhs72 : 1581105131765.png

or this from my 96 Fleetwood Limo:
192562

accomplish the same thing. The square solid steel does all the lateral and up/down stabilization needed and keeps the 1 1/2" solid steel sway bar from ripping out the mount.
 

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192564

The frame brace is welded on the side and the sway bar mount is bolted thru the brace and the frame.
 

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View attachment 192564
The frame brace is welded on the side and the sway bar mount is bolted thru the brace and the frame.
Yeah I saw those, and welding them in place definitely seems like a solid choice(ha). I was more wondering about just hammering a tube into place elsewhere and welding, and not having to disturb the sway bar area, but after taking a look at my car last night, it seems like under the sway bar is just the best place, all things considered.

That being said, how did you guys set up the sway bar bracket bolts/nuts with the limited accessibility into that part of the frame there?
Mark, looks like you drilled and tapped the plates and thread right into those without any backer nut inside the frame?
 

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As you see in the above picture, bracket under the frame, weld the lock nut into the frame, bolt thru the bottom with another lock nut ( belt and suspenders theory)
The Hotchkis 1 7/16" hollow front bar has more extreme bends than OEM which makes it longer than OEM and so makes it only as much roll resistance as a 1 1/4" solid bar. Other after market bars too. Not much improvement. The Quickor 1 1/2" solid front bar is also shorter than either bar and so has more ability to rip the mounts off the frame unless using an attachment method that is more stable. The Quickor front bar is 160% stiffer than a 1 3/8" solid bar. I stopped attempting to convince forum members long ago that the optimal balance was dynamically achieved by using F+R sway bars of the same roll resistance, ideally the same diameter, whether hollow or solid. Sacrilege apparently, even though a lot of road course testing with various shocks, wheels, tires and everything else that effects handling showed it's true.
 

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Yeah I saw those, and welding them in place definitely seems like a solid choice(ha). I was more wondering about just hammering a tube into place elsewhere and welding, and not having to disturb the sway bar area, but after taking a look at my car last night, it seems like under the sway bar is just the best place, all things considered.

That being said, how did you guys set up the sway bar bracket bolts/nuts with the limited accessibility into that part of the frame there?
Mark, looks like you drilled and tapped the plates and thread right into those without any backer nut inside the frame?
Brian, you have a PM, conversation whatever.

Mark: Snowman-33
 

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Over the last couple weekends I was able to implement my front end chassis brace/front swaybar mount. The design changed a bit and I'm pretty happy with it. Here's a sketch of the concept.



And here's the execution...















Determined mounting location so that it will clear the idler arm - used a short stub of tube on a nut/bolt as a mock up


Modified the brackets to conform with the frame and move the tube up as far as possible.


Mark out area on frame to clean up for welding


Brackets were sandblasted, painted, then the paint removed from the weld area.


Loosely assembled and welded the brackets in - not my best welding, but it will hold.




To mount the sway bar, I should have made the brackets a bit longer (but I didn't...) so I had to weld on some extensions so the bar could be mounted back farther which helps with spindle clearance. These welds are much better...







It's a close fit between the idler and the swaybar...but it clears


I was able to use M10 locking tab nuts with wings on them for easy install without needing to hold the nuts


The brackets were welded to the frame, one of the 1" nuts was welded to the pipe which was cut about 1/8" shorter than it needed to be. The other 1" nut was hammered in the pipe, then the bolts were tightened so the hammered in nut could slide to where it needed to achieve the correct width for where the brackets were welded to the frame. The last nut was tacked and then the pipe was removed and welded out. Sorry, no good pictures of those steps...

Final install (less painting/finishing and a couple minor things on the control arm end of the swaybar)
 

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One thing that I did run into with the above frame brace/swaybar mount was that the swaybar ends up being mounted about 2.5" lower than it used to be. I initially didn't give this much consideration given what others have done - I figured that I would just shorten the end links at the control arm a couple inches and that would be fine. It soon became obvious that it would be a problem when articulating the suspension through it's range of motion...

The tie rod end at the spindle and the swaybar want to occupy the same space when at full compression and full steering lock. This is shown with a 1/2" longer swaybar end link (no compression on the rubber bushings and the bolt is thread in about 2 threads to the heim joint), so making it shorter would make it even worse.


While an unlikely combination of events, if it happened the risk of damage, and more importantly, safety of myself and others was high. Moving the sway bar mounting back a few inches helped this quite a bit. The swaybar can't move back any farther since it clears the frame by ~1/4" on each side at the ends since this is where the frame widens to house the coil springs.

I don't know if anyone else has run into this issue or not? If so, how did you solve it?

My current plan is to make the swaybar end links 1" to 2" longer which should push the sway bar "up" enough to clear the tie rod end. I could also put a 1/4"-1/2" saddle on the lower control arm to effectively lower the bump stop location to limit suspension compression travel or a combination of these two solutions.

The swaybar looks pretty level (not sure if that matters?) as shown below, at ride height, when mocked up with a 1/2" longer end link, so hopefully I can just make the end link longer and that will solve the problem.
 

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I think you're in slightly uncharted waters with this particular custom concoction, haha. I really appreciate you taking the time to document and share this process though.

I do want to get some kind of brace bar in the front of my track car to minimize flex at full lateral load and keep the front tires more square on the ground. All good inspiration!
 

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IF that is the 1 7/16" Hollow front sway bar from Hotchkis:
You would have a much easier time w/ fit by replacing it with any solid 1 1/4" front bar and the roll resistance of both bars would be about the same. Hotchkis was heavy into cosmetics back when they designed this bar (see their Engine Bay Brace-waste) and wanted to have the FAT bar. They made two mistakes. The hollow 1 7/16" bar had to bend more than OEM, which made it longer , which reduced it's roll stiffness, combined with hollow= about the roll resistance of everyone else's 1 1/4" solid bars.
The brace is terrific and has the effect of making any front bar more effective so you lose nothing by swapping to the 1 1/4" solid. Any 1 1/4" solid rear bar or any 1 3/8" hollow rear bar makes for a more neutral B-body. D-body too.
 

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Chicagoareabmx - I think that's the nicest way I've heard anyone put that :) Usually it's WTF...you want to do what?, I don't know, good luck, you're on your own.

scot - the front bar is the 1-5/16 hollow bar and the rear is a 7/8" "adjustable" (by changing the end link location) - both from SpeedTech. Not looking to auto cross it, but like a neutral to slight understeer handling car on long sweeping curves.
 

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Speed Tech front bar, like my comments on Hotchkis, cosmetic goof. A 1 5/16" hollow bar has the roll resistance of the OEM 1 3/16" solid bar, if it's the same length. . Clueless to think the weight savings of a hollow bar accomplishes anything and to make it worse, like the Hotchkis bar, it appears longer with more radical bends in order to fit, which makes it have even less roll resistance than the OEM bar, which is why you're having the hassle fitting it with your brace. The brace... which is great and the added weight detracts not one tiny bit. Your 7/8" adjustable rear bar? Given the geometry of the rear suspension I see why it's 7/8" as that's also less roll resistance than the OEM 1 1/16" regardless of end link location or if it's hollow and with the front Speed Tech bar they retain the OEM understeer bias just with more body roll. My handling recommendations have nothing to do with autocross, given the weight distribution of B-bodies, having F+R sway bars of equal roll resistance makes for a more neutral dynamic but the front weight bias is tough to over come. You can induce massive oversteer with a giant rear solid bar and a smaller front bar but that's counter productive. A better way to get all the effects of the Speed Tech bars is find a junk yard with any base FE1 suspension and use the 1 1/16 front bar (~5 dollars?) and no rear bar. Speed Tech and FE1 OEM = a difference without a distinction.
 

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Fix until broke, couldn't be more true, haha. Trust me, I understand slightly uncharted waters that might not make sense to a lot of people, but can be highly effective for our oddballs. Case in point, my choice of road course mule:
192754


I'm fighting pretty bad outside shoulder wear on my car when tracking, despite big ol' sway bars, tons of posi caster and -2.0 camber. Next moves will be a front frame brace(Scots rear brace has seemed to help my car a lot), shorter upper control arms with delrin bushings and tall upper ball joints, so the DIY front brace is very relevant to me at the moment.

This car you're modding, is it a wagon? Older gen
PITTRACENICE.jpg
sedan? I forget at the moment.
 

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Speed Tech front bar, like my comments on Hotchkis, cosmetic goof. A 1 5/16" hollow bar has the roll resistance of the OEM 1 3/16" solid bar, if it's the same length. . Clueless to think the weight savings of a hollow bar accomplishes anything and to make it worse, like the Hotchkis bar, it appears longer with more radical bends in order to fit, which makes it have even less roll resistance than the OEM bar, which is why you're having the hassle fitting it with your brace. The brace... which is great and the added weight detracts not one tiny bit. Your 7/8" adjustable rear bar? Given the geometry of the rear suspension I see why it's 7/8" as that's also less roll resistance than the OEM 1 1/16" regardless of end link location or if it's hollow and with the front Speed Tech bar they retain the OEM understeer bias just with more body roll. My handling recommendations have nothing to do with autocross, given the weight distribution of B-bodies, having F+R sway bars of equal roll resistance makes for a more neutral dynamic but the front weight bias is tough to over come. You can induce massive oversteer with a giant rear solid bar and a smaller front bar but that's counter productive. A better way to get all the effects of the Speed Tech bars is find a junk yard with any base FE1 suspension and use the 1 1/16 front bar (~5 dollars?) and no rear bar. Speed Tech and FE1 OEM = a difference without a distinction.
scot - thanks for the info. I have the stock 1-3/16 bar and I did a rough comparison between them and they looked the same (same bends, same locations, same shape, etc - just to make sure that they didn't ship the wrong bar), but I'll look at them in more detail this weekend. I'd think that if it were longer than the stock bar that I wouldn't have had to slide it back as far to make it fit decent around the tie-rod ends? It's definitely not longer from side to side compared to stock as the rubber bushings were "into" the bend in the OEM sway bar mounting locations.

No illusions about weight savings with the hollow bar - it's what was in the package (along with the rear bar). I made the (somewhat uneducated) decision to purchase a complete suspension system rather than try to re-invent the wheel piece by piece. I'll give it a shot as it's intended, but good to know of other bar options in case I'm not happy with how this work out.

Chicagoareabmx - the car is a 96 Roadmaster Wagon with a 6.6 Duramax engine swap.

A few more details here...



 

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If you look at the picture I sent of my brace, it's <half the height of yours. Look at the bolts for the steering box and how the front bolt lines up with the OEM sway bar mounting hole. Your brace is just too altered in both dimensions to work right. I know this is not what anyone would want to hear but as it is, you can't get clearance through full lock. Shorter end links makes it worse. Even if the OEM front bar is shorter that will not help (only accurate way to measure both bars is with a cloth tape measure, walking the tape over the whole length of each bar), though the 1/8" thinner OEM bar might just miss the steering knuckle. The 1/8" thicker SpeedTech bar does force you to slide the mount too much rearward (see the OEM sway bar mounting hole), to where the frame bend starts interfering (wrong guess, Hans! I thought a Die Hard homage might lighten the mood). Before you start cutting out your brace, try the OEM bar using the OEM mounting holes as a guide for new holes in your brace.
PS Being it's a wagon, the weight distribution is actually much closer to balanced than any B-body sedan. The SpeedTech rear sway bar is a HOLLOW 7/8" so overcooked pasta might have given more roll resistance than that! Seriously. If you can find a now discontinued Hotchkis wagon rear bar or any other solid rear wagon bar they would be so much better a balance for (hopefully) being able to use the OEM front bar. Then sell the SpeedTech bars to a someone who thinks 24" wheels look cool and improve performance.
 

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1996 Fleetwood Limo... The clearance with a 1 1/2" sway bar gives you a vivid look at how cutting your brace down would allow you to use any front bar.
192767
 

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If you look at the picture I sent of my brace, it's <half the height of yours. Look at the bolts for the steering box and how the front bolt lines up with the OEM sway bar mounting hole. Your brace is just too altered in both dimensions to work right. I know this is not what anyone would want to hear but as it is, you can't get clearance through full lock. Shorter end links makes it worse. Even if the OEM front bar is shorter that will not help (only accurate way to measure both bars is with a cloth tape measure, walking the tape over the whole length of each bar), though the 1/8" thinner OEM bar might just miss the steering knuckle. The 1/8" thicker SpeedTech bar does force you to slide the mount too much rearward (see the OEM sway bar mounting hole), to where the frame bend starts interfering (wrong guess, Hans! I thought a Die Hard homage might lighten the mood). Before you start cutting out your brace, try the OEM bar using the OEM mounting holes as a guide for new holes in your brace.
PS Being it's a wagon, the weight distribution is actually much closer to balanced than any B-body sedan. The SpeedTech rear sway bar is a HOLLOW 7/8" so overcooked pasta might have given more roll resistance than that! Seriously. If you can find a now discontinued Hotchkis wagon rear bar or any other solid rear wagon bar they would be so much better a balance for (hopefully) being able to use the OEM front bar. Then sell the SpeedTech bars to a someone who thinks 24" wheels look cool and improve performance.
scot - I appreciate your feedback, though I think you might be taking a few things out of context?

The brace I installed lowers the swaybar 2.5" below the frame and the one you show is 1.5" below the frame. I'm guessing that if you were able to do this using the factory swaybar mounting holes (which is what it looks like), either your swaybar arms are longer and/or have more vertical offset than mine, and/or you too have an interference with the tie rod ends at full lock and full compression.

I don't have any plans to start cutting out the brace or moving the swaybar mounting location. The arms of the swaybar clear the frame in the back, it clears all the steering components up front and I'm confident that with extended links to the control arms, it will clear the tie rod ends when at full steering lock and full compression. I'm not sure where an 1/8" larger diameter swaybar is forcing the mount too much rearward or where the 1/8" smaller OEM bar would clear the steering knuckle (tie rod end?). Could you explain this a different way maybe? I'll try and get some detailed side by side comparisons between the OEM and SpeedTech front bars this weekend and will post what I find here.

Given that there was no rear swaybar from the factory, I'm betting that even the piece of overcooked pasta I have will be better than what it started with. Given others feedback on how much improvement the Crown Victoria rear swaybar makes (very similar to this design) I'm optimistic that it will be better than stock. With the tubular control arms I'm planning to use and being a wagon, there are not many rear swaybar options that I've found.
 

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"I'm not sure where an 1/8" larger diameter swaybar is forcing the mount too much rearward "
No it's the 2 1/2" lower mounting point for any sway bar that is forcing the mount too much rearward. I doubt any aftermarket or OEM sway can accommodate that 2 1/2" lower brace mounting point without much longer end links. You wrote shorter would only make things worse.
My (1.25 " actually) brace does not lower the bar enough to cause any contact at any point regardless of suspension travel (many years now on the Limo and before that over 12 years on a 94 SS)
One of your pictures showed scratches on the 1 5/16" bar so I thought that one issue might be mitigated with a 1 3/16" OEM bar. Longer end links might well get it done but my comment about the shape of the frame on the passenger side maybe being an issue was because the mounting is farther rearward. Frame bends outward there a bit
.
Previously Hotchkis discontinued it's 1 1/4" solid rear sway bar for wagons but...
1978-1996 GM B-Body Sport Sway Bars Wagon from Hotchkis Sport Suspension
Applications: SKU 2206 Is designed to fit wagons only. Sedans use SKU 2205.
Hotchkis Sport Suspension 2206 1978-1996 GM B-Body Wagons Sport Sway Bars. Improve cornering and straight line acceleration of your 78-96 GM B-Body wagon by reducing body roll with a set of Hotchkis Performance Sway Bars. Hotchkis bars feature lightweight hollow construction and include greasable polyurethane bushings end links and brackets. Hotchkis bars are powder coated for durability and tested and tuned to ensure the best performance possible. 1-7/16 in. Hollow Front 1-3/8 in. Hollow Rear. Note: Our rear bars is now hollow and utilizes a unique cnc machined mounting pad. Mounts like the factory bar and retains the same roll stiffness of our previous design. SKU 2206 Is designed to fit wagons only. Sedans use SKU 2205.
1 3/8" even if hollow will give you vastly more rear roll resistance than any mounting system of a 7/8" hollow rear bar and a much more neutral overall handling. Of course if your goal is an understeer bias then by all means the 7/8" is the way to go.
Sadly your SpeedTech lower control arms are not (drilled or maybe they are! If so, disregard the rest of this post) made to use even SpeedTech's OEM mounting system sway bars but there is no reason you could not fabricate (I've seen your pictures!) a mount for the Hotchkis 1 3/8" rear bar using your SpeedTech LCA's, which are not really any different than many after market tubular LCA's. I did use 1 1/2" solid F+R sways on a Buick Roadmaster Wagon and found it neutral if a little severe in roll resistance.

Mostly I'm just brainstorming to see how much I remember.
 

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Just to close this out - here's what I ended up with to get the front swaybar to fit.

1" longer end links give plenty of clearance to the tie rod ends at full suspension compression and through the whole steering travel. I could probably make them 1/4" shorter, but will leave them as shown for now.




I was able to go compare the OEM Wagon and the SpeedTech front swaybars. I was incorrect in my earlier assumption of the OEM diameter: it is not 1-3/16, more like 1-1/8


The Speedtech bar is more like 1-3/8" once the powdercoat is removed


I was able to overlay the two bars pretty well and there's very little length difference between the two bars from the frame mounting point to the end links. Not an appreciable difference in my opinion, nothing that is going to make the OEM bar fit any better/worse than the SpeedTech. If I should decide to change front swaybar size, most anything for a B body should fit, even with the lowered frame mounting point.


 
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