Barracuda Challenger Forum

Author Topic: Torque boxes  (Read 1211 times)

Offline Road_Runner

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Re: Torque boxes
« Reply #15 on: January 11, 2017 - 03:44:32 PM »
I re-read my initial comments and see that I mentioned the conformal SFC's but never really said that I put them in my own car, by myself and I'm a licenced bodyman. Without any exaggeration, the lft one was up and down at least 12 times as I fitted, marked, ground and clamped them to get them to fit the brand new AMD floor pan. The rt one was better and was only in and out 6-7 times. Having a helper would make the job much easier as they could hammer where needed why the installer works below. It's fiddly, but, as mentioned, it looks right under the car and the fact that the whole floor pan is now part of the structure, makes the whole thing worthwhile IMHO. It took two days of screwing around, and was admittedly, the first pair I'd installed, so if your "guy" has been there and done that, he may be quicker, but there's no way in hell that the job'll be done in 3-4 hours either. Your car, your call. Good luck  :cheers:

I have a set of the preformed US Car Tool Chassis Connectors to go in both my Roadrunner & Barracuda so would definitely like to do as much of the prep work myself as I can.  I've read some installation descriptions, but they were a little light on details about exactly what to do prep-wise.  I've read that the ridges on the connectors may or may not line up exactly with the corresponding spot on the floor pan, is the idea to grind the connectors where necessary for it to lay flat against the floor on each end and as closely as possible fit tight in the bends & curves as well?  How much of a gap is OK to leave for the weld to fill?  I know I'll need to clean off all undercoating between the two subframes to be connected, anything else you can share? 

Thanks, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black




Offline jimynick

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Re: Torque boxes
« Reply #16 on: January 11, 2017 - 08:25:46 PM »
Sure, the gap, according to my now long-dead welding teacher, should be the diameter of the welding rod. BUT, if you know what you're doing with a MIG, you can go 2-3 times that and crank the wire speed a bit to fill; less than an 1/8th and preferably a 1/16th". I always started on the thicker connector and "washed" the puddle over onto the floor panel. That way you're not so likely to blow through, said floor. I used a Sharpie, the MkI eyeball and a 4' grinder on the connector to achieve the fit. You can do it, it's just a wee bit time consuming. Obviously, you grind the previously marked area where the connector meets the floor and you only need an inch wide clean. I also used a small angle-headed air grinder and either 50 or 80 grit Rol-Loc pads. Give the edge of the connectors a kiss with the 80 grit to make sure you're starting with a clean, conductive surface, too. Stitch weld them and jump back and forth to reduce heat buildup and warpage. When I finally got the whole thing welded (and you will have people tell you you only need to stitch them) and after grinding the welds, I used a 3M bonding kit as a seam sealer to smooth the transition from the floor to the connector; you could also use straight seam sealer. If you're careful with your application and use a cheap flux brush to draw it out, it looks like you actually know what you're doing. LOL Check your positioning, as it's easy to get them in on a poor angle and you'll also see that there's a sweet spot where most of the contours kinda like each other. Sounds like a lot, but it's really just being careful and taking your time. Have fun and post some pics of the finished product. You'll be glad you did this.  :thumbsup:

Offline Road_Runner

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Re: Torque boxes
« Reply #17 on: January 11, 2017 - 11:37:43 PM »
Sure, the gap, according to my now long-dead welding teacher, should be the diameter of the welding rod. BUT, if you know what you're doing with a MIG, you can go 2-3 times that and crank the wire speed a bit to fill; less than an 1/8th and preferably a 1/16th". I always started on the thicker connector and "washed" the puddle over onto the floor panel. That way you're not so likely to blow through, said floor. I used a Sharpie, the MkI eyeball and a 4' grinder on the connector to achieve the fit. You can do it, it's just a wee bit time consuming. Obviously, you grind the previously marked area where the connector meets the floor and you only need an inch wide clean. I also used a small angle-headed air grinder and either 50 or 80 grit Rol-Loc pads. Give the edge of the connectors a kiss with the 80 grit to make sure you're starting with a clean, conductive surface, too. Stitch weld them and jump back and forth to reduce heat buildup and warpage. When I finally got the whole thing welded (and you will have people tell you you only need to stitch them) and after grinding the welds, I used a 3M bonding kit as a seam sealer to smooth the transition from the floor to the connector; you could also use straight seam sealer. If you're careful with your application and use a cheap flux brush to draw it out, it looks like you actually know what you're doing. LOL Check your positioning, as it's easy to get them in on a poor angle and you'll also see that there's a sweet spot where most of the contours kinda like each other. Sounds like a lot, but it's really just being careful and taking your time. Have fun and post some pics of the finished product. You'll be glad you did this.  :thumbsup:

I really appreciate the tips, I try to do everything I can do myself so it doesn't hurt so much when I have to pay someone else to do the rest!  Plus, there's nothing like knowing I built that, or at least as much as I could!

Thanks, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black


Offline nsmall

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Re: Torque boxes
« Reply #18 on: January 12, 2017 - 01:31:49 AM »
Well, after studying and studying, I am still not sure what to do.

The Hotchkis frame rail seems like a good idea, but expensive and it hangs down.

Brad and Neil (CP) talk about making your own.  Thinking my friend whose 50 year expert metal guy could hook me up.

As for the US Car Tool, seems like this may be a real mess.  I dont have a welder or grinder for that matter.

Should the home made frame connectors be installed with all 4 tires on the car? 

Thanks for all your help

Offline soundcontrol

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Re: Torque boxes
« Reply #19 on: January 12, 2017 - 04:51:37 AM »
I recommend US Cartool, its not that bad, takes a day of grinding and welding, but it looks good and works well.
/ Ken
Restoration thread: http://www.cuda-challenger.com/cc/index.php?topic=102525.0
topic=108917.new#new

Offline Road_Runner

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Re: Torque boxes
« Reply #20 on: January 12, 2017 - 11:09:04 AM »
The main reason I picked the US Tool connectors vs the others is that after installation I plan to recover them with the same undercoating as the rest of the cars and they look 100% original.  Only Mopar fans will know they didn't come that way which is a big plus for me.
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black

Offline cudabob496

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72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.
Up to 4000 RPM, Warp Speed, Up to 5000, Rediculous Speed, Up to 6000 RPM, Ludicrous Speed!

1999 Trans Am, LS1, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

Offline HP2

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Re: Torque boxes
« Reply #22 on: January 12, 2017 - 05:25:07 PM »
Well, after studying and studying, I am still not sure what to do.

The Hotchkis frame rail seems like a good idea, but expensive and it hangs down.

Brad and Neil (CP) talk about making your own.  Thinking my friend whose 50 year expert metal guy could hook me up.

As for the US Car Tool, seems like this may be a real mess.  I dont have a welder or grinder for that matter.

Should the home made frame connectors be installed with all 4 tires on the car? 

Thanks for all your help

To simplify it all and keep costs low, get these: https://www.summitracing.com/parts/cee-3043/overview/make/plymouth/model/barracuda

Then have your body guy weld them in.

Yes, you can make you own for about $30 in materials, but if you body guy is reluctant to fab any thing at all, he'll charge enough of make the units above a deal.

Offline nsmall

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Re: Torque boxes
« Reply #23 on: January 13, 2017 - 01:13:45 AM »
Thanks HP2

REALLY appreciate your advice.  I have three kids, two under 15 months so I am going to buy these as I have no time and want to finish this build.

https://www.summitracing.com/parts/cee-3043/overview/make/plymouth/model/barracuda  That was the link you gave me

I may have my body guy cut holes as Brad suggests and add round tubes for extra strength.  Does that sound like a good I idea to beef them up?  Im assuming these are supposed to be put in under the floor boards outside of the frame rails or do they fit over the frame rails?  Does that sound correct?  I'm assuming you know more than a summit employee.  Just confused where they are installed as they look like they have some bolt in type bracket.

My welder friend has a lift, but not one you drive on to.  Will that type of lift be okay to weld these in with the cars frame resting on the lift?  Will it be better to have the engine, tranny, and rear end out to reduce sagging and then install them?

Im assuming I should sand and paint with a good rust inhibitor paint before install them?

Lastly, if I get torque boxes, which ones should I buy (US Tool) and do the torque boxes go in first?

Thank you very much.  First and last car, trying to do everything once.

Neil

Okay, just downloaded the instructions.  here is paragraph 1

INSTALLATION INSTRUCTIONS
P/N: C3043
WELD
-
IN SUBFRAME CONNECTORS
Competition Engineering Weld
-
In Subframe Connectors are engineered to provide a solid connection
between the factory front subframes and Competition Engineering's line of Formed Rear Frame
Rail Kits.
Competition Engineering's Formed Rear Frame Rail Kits must be used with these subframe connectors.
This kit will also allow you to relocate the leaf springs inboard, mounted directly under the new frame rails. If
you do not wish to install the r
ear frame rails you may purchase one of our bolt
-
in subframe connector kits
and weld them in place. Installation will require channeling of the factory floor pan and removal of the factory
rear frame rails. 
NOTE: When installing this product on a Barrac
uda, 1
-
1/2 must be cut off the front of the connector to keep
the stock spring eye location

Now I am thinking it will be easy to just build my own as I dont want to cut up the car and relocate anything.  Not trying to be annoying, just trying to do this with the least amount of cost and effort.

Thanks again,

Neil
« Last Edit: January 13, 2017 - 01:27:41 AM by nsmall »

Offline HP2

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Re: Torque boxes
« Reply #24 on: January 13, 2017 - 11:57:50 AM »
Thanks for catching that. I did not check instructions to see these  are for back halved cars. No, you do not want to use these.

Here is a simpler approach and an even better price is here: http://www.manciniracing.com/maebo19.html

These are what I was after before - a basic bolt in connector that saddles the rear frame rail and butts against the front frame rail that hangs under the floorboard so there are no mods to any of the existing body structure. Instead of bolting, these can be welded. Tube size also means you do not need to modify for e-brake cable clearance. This is the fastest, easiest method of installing significant flex reduction with minimum effort. At this price, if your welder spends anything more than a hour making similar units, his price will exceed these.

The added holes and tubes are a great way to increase rigidity of a tube. However, since you are paying by the hour for the guy with the tools, adding all that reinforcement is going to add time. Half a days work to a home hobbiest is nothing. Paying for half a day for a welder to modify parts increases cost exponentially. I'd suggest skipping this step as the simple addition of connectors is a HUGE step forward.

These typically do comes painted, but you may want to repaint and finish them as much as possible before installation. There will also be post install finishing required as well since they are being welded in and this will burn the paint at those points, but yes, you want other areas of the tubes finished before install as they may become inaccessible.

With these connectors and the idea of cost savings, I'd skip installing the torque boxes. They aren't entirely an either/or situation, but they both accomplish very similar things. Would including them add more rigidity, yes, but I've never seen a test to say how much change there is between SFC and TB vs both so I'd have to say we are looking at changes that won't be felt in the seat of your pants. However, if you do decide to install, I'd don't think it matters which goes in first as either one will require slight mods to fit with the other.  Not sure who is the best option on these. I have seen sellers who advertise exact restoration reproduction styles and other who say they are performance oriented, similar style, heavier gauge. In my experience, the few I have installed required custom fitting to work well, so in addition to be more costly in the initial purchase compared to SFC, they also are going to cost more to install.

Offline nsmall

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Re: Torque boxes
« Reply #25 on: January 13, 2017 - 05:25:03 PM »
THANKS HP2.

Man I love this site.  This hobby is flippin expensive, but I really enjoy my car and this site has really helped me get closer to building a car I never thought I would own.

As for drilling holes and adding the round tubing for extra strength like brad did, looks like it would NOT be possible on these frame connectors as these ones hug the frame rail.  Is that correct?  As for welding, Im assuming I have the welder weld this in everywhere it is possible to for the best possible strength?

I can't weld well and have no tools to cut metal so it looks like you found the best possible option for me as I will hire a welder to weld these in.  Really appreciate your help.

Thanks again,

Neil

Offline HP2

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Re: Torque boxes
« Reply #26 on: January 13, 2017 - 07:55:07 PM »
The rear mount is a  saddle that wraps around three sides of the subframe. The connecting tube is simply a straight tube. In some places it may touch the floor, in other it won't. The front mount sits flat against the front sub frame. A few inches of weld on each side of each end of each connector, and they are in.

Here is a B body example. Photos aren't great, but you can kind of see the concept. Notice the zip ties around the tube, because it doesn't butt against the floor. Optimal, no, but they make a significant difference in body flex. Without these, I could not open the door when a tire was in the air. With them, it opened and closed the same in the air as on the ground, and this was in a pretty solid car that required no major structural surgery

 :cooldancing:





« Last Edit: January 13, 2017 - 07:58:49 PM by HP2 »

Offline nsmall

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Re: Torque boxes
« Reply #27 on: January 13, 2017 - 11:25:41 PM »
HP2...sorry for all the questions.  My welder friend has a lift, but not one you drive on to.  Will that type of lift be okay to weld these in with the cars frame resting on the lift?  Will it be better to have the engine, k frame, front suspension, tranny, and rear end out to reduce sagging and then install them?  Another option is I go to a different friends house who can weld and has a lift you actually drive the car onto the ramps.  Does it matter?

Thank you very much. 

Neil

Upon futher research...HP2, please dont hate me.  I found these tonight...http://www.manciniracing.com/maefrcokit.html
Is this true, floor pans DONT need to be modified with these ones?  I have read a bunch of US car tool peoples experiences, not Mancini's.  One fact seems consistent, welds to the floor plans help with strength, yet I dont want to cut up the floors, but I dont mind spending $90 more for something thats a considerable improvement.    Anyone got an opinion on the link I just posted?

Thanks again!  I finally understand what I want to do, sorry it took so many words folks... :thumbsup: :naughty:
« Last Edit: January 14, 2017 - 02:12:54 AM by nsmall »

Offline soundcontrol

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Re: Torque boxes
« Reply #28 on: January 14, 2017 - 08:31:32 AM »
I had jackstands under the rear axle and front suspension when welding. Car was totally assembled at the time.
/ Ken
Restoration thread: http://www.cuda-challenger.com/cc/index.php?topic=102525.0
topic=108917.new#new

Offline HP2

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Re: Torque boxes
« Reply #29 on: January 14, 2017 - 01:44:32 PM »
HP2...sorry for all the questions.  My welder friend has a lift, but not one you drive on to.  Will that type of lift be okay to weld these in with the cars frame resting on the lift?  Will it be better to have the engine, k frame, front suspension, tranny, and rear end out to reduce sagging and then install them?  Another option is I go to a different friends house who can weld and has a lift you actually drive the car onto the ramps.  Does it matter?


That would be fine. There are a lot of different opinions on how best to put these in. None are absolutely wrong and tend to fall into to prevailing camps; on the wheels in an as driven load, or in the air in an unloaded position. Within this you have the make it look stock, make it look perfect, make it retain current position, support but don't alter, and a few other opinions.

My $.02 worth; unless you are part of the very, very small percentage  whose racing success depends on the .01 second difference have a perfectly square, plumb, and straight chassis produces, a lot of effort  in producing a perfect car will either A)get in the way of finishing  the car B) get in the way of enjoying the car, or C) never even be notice for any improvements produced by the effort. Should we all try for this state, sure. But factory tolerances allowed  up to .25" of slop in some of the chassis measurements, so depending on what we started with, we could be polishing a  piece o' poo. Not sure of your age and many of us have forgotten the times back then, but it was the era of peace, love, and pass the gangha. Not all assembly line workers where in their right mind during the assembly of these vehicles and a few may have passed through outside the allowable tolerances.

You said the car is going in for paint. You haven't said if it is gutted to a shell or partially dis-assembled or simply has the trim removed? If the former, then make the effort to square things up to ideal. If the latter, then lock in what you have so all you panels still align well and not ruin your new paint job.


Upon futher research...HP2, please dont hate me.  I found these tonight...http://www.manciniracing.com/maefrcokit.html
Is this true, floor pans DONT need to be modified with these ones?  I have read a bunch of US car tool peoples experiences, not Mancini's.  One fact seems consistent, welds to the floor plans help with strength, yet I dont want to cut up the floors, but I dont mind spending $90 more for something thats a considerable improvement.    Anyone got an opinion on the link I just posted?

Thanks again!  I finally understand what I want to do, sorry it took so many words folks...


IMO, these are similar to the US car tool units.  Yes are CNC design, cut, and bent. But remember above, .25" factory variation? These may require the  same amount of  trail fitting (time/money) to fit as the US Car Tool units. FWIW, neither require modifying the floor pan, per say. They require modifying the connector to match the floor pan. When you add up the continuous length of this contoured cut x4 sides, that is why it takes so stinking low to get some of these to match up.  I'll also add regarding these style of connectors, that while they integrate the floor pan and with continuous weld and are very strong, their weakest point is still the very small cross section area under the rear passenger foot well, which is a smaller cross section than most regular tube style of connectors. Until someone does an exact one for one comparison with a degree of deflection result, its an intellectual debate about which layout is actually better. IMO, for simple bang for the buck benefit, the $99 bolt in style I posted previously are hard to beat.

Thank you very much. 

Neil


You're welcome.

Tony
« Last Edit: January 14, 2017 - 01:50:53 PM by HP2 »