Torque Boxes, inner fender braces, and Subframe Connectors...

[MxRacer855]

I'm in the process of restoring my undercarriage along with a few other sections right now. If I installed inner fender braces, subframe connectors, and torque boxes on my '68... would I notice a difference in the rigidity and overall solid feeling of the car? I searched around on here for a bit and didn't quite find a direct thread on how much of a difference these additions actually make.
Any input would be more than helpful. Thanks!
Jeff

[c00nhunterjoe]

Subframe connectors- definately.

Inner fender braces- doubtful. The torsion bars and front suspension puts the load lower then a traditional coil spring setup. Inner fender braces benefit coilspring setups because the load is distributed to the upper end of the fenders. For a street driven mopar i would put that money into boxing your lower control arms and purchasing tubular upper control arms.

[MxRacer855]

Thanks Coonhunterjoe!
I Would Like To Purchase That Hotchkis "TVS" kit, but have to hold off on that for now. So in the meantime, should I just go with subframe connectors and torque boxes? Just leave the inner fender braces out?

Jeff

[tsmithae]

Jeff, I am going just that route.  I will be using the subframe connectors and the torque boxes for my street-driven car.  I have no intentions of rally driving or anything crazy. That being said, I will be boxing my LCAs, upgrading torsion bars and sway bar, and rebuilding the entire front end. Do I expect my car to handle like modern sports car, no.  Will it be better than stock, most definitely!   

[Mike DC]

Torque boxes & subframe connectors are probably the biggest improvement.  

Some guys do HUGE subframe connectors, like 2x3 rectangular tubing, etc - it isn't necesary most of the time.   The SCs only need to be stiff enough so that area is not the weakest link in the chassis anymore, they don't need to be giant.  


Next is probably the lower radiator support bracing between the front rails.  The car needs this because the K-frame is not welded into place.

The shock towers are probably last after that.  But I would still do them.  IMO bracing the unibody is one of those things that doesn't really have a downside.  The cost isn't much, the stuff doesn't weigh a whole lot, and these days you can get the bracing from a catalog pre-shaped so you don't need to hack the car to install it.  In all the years I've been in this hobby, I cannot recall ever hearing anyone say they added SCs & torque boxes and couldn't feel a difference.

-------------------------------------

If you wanna stiffen up the feel some more, look into gusseting the K-frame itself.  The LCA mounting tubes can tear out of the walls of the K (metal fatigue).  And the steering box mount flexes even when the K-frame is brand new.  I can't remember off the top of my head but some company was selling braces to weld onto the steering box mount.

[c00nhunterjoe]

Check with firmfeel.com they sell alot of the do it yourself stuff and are a great company to deal with.

[fy469rtse]

one of my cars that I had done, got to drive a comparison to it , side by side , firmer stiffer, better handling , yes to all ,
I would do all jeff , frame connectors welded in type
torque boxes
lower radiator brace
gusete plates to steering box mount, it stop's flex there in the K frame, gussett the Kframe or at least fully re weld it, only spot weld's from factory
and if the current range of inner fender braces were out when i did my car, i would have added the inner fender braces, not afan of the tube type, I like the flat plate type that could look factory
 

[MxRacer855]

Thanks for all of the opinions and information guys.  What I got from all of this is to do as much as I possibly can, but at the very least, start with subframe connectors and a full set (4) of torque boxes.

With that in mind, next question:
Any suggestions on sellers?

I read good reviews on the US Car Tool torque boxes that you can get for pretty cheap on eBay, so I think I'll go with those. What about for the rest of it though? Would a company like Hotchkis be a good one to go with regarding the SF Connectors?

Jeff

[tsmithae]

It depends on where you are with your build.  Do you have a full interior that you are reluctant to remove?  Then you will be looking at bolt-in ones from Hotchkis or similar that require little to no welding.  If you have a shell you would do yourself a favor by going with something welded in.  Yet again, my  , I went with US Cartool and while they weren't a perfect exact fit, I am VERY happy with them (I will add that I have replaced the torsion bar crossmember and the full floor so any differences could very well stem from that). 

[Mike DC]

 
These cars weren't precision built in the first place.  It's impossible to make a part that will fit every car perfectly, even the undamaged survivors. 

[fy469rtse]

Jeff, I made my own, very similar to the us car tool ones, you will have to trim file them in places to fit the floors, I welded in a false top, to box them before I welded them in,
Have a look for my build thread I think I put some photos up early, shows how I also put a lip on them to where they sit against floor,
I also drilled holes in increments to them to look factory, , lots of posted photos in threads on here
Go the us car tool ones Jeff , once in can be made to look factory , check out all the build photos and see what suits you

[ottawamerc]

Definitely go for the USCartool parts for a couple of reasons 1: welding the items in are the only way to get the full benefit from any frame stiffening, bolted ones will still flex. 2: USCartool is extremely professional company with some of the best customer service I have ever had from any parts sources! and reasonable prices. 3: The parts FIT! , of course there is some grinding and hammer work to get them in tight but its explained in the instructions and like it was said before these cars were not precision built in the first place. 4: I just installed frame connectors and front and rear torque boxes in my 71 that was completely restored last year so I can attest that they can be installed at anytime during your build but earlier would be prefered
Good luck and post pics

Scott

[green69rt]

Reinforced K frame  (I think you can get the parts to DIY)  http://www.firmfeel.com/reinfkfram_b.htm

Reinforcement for the steering gear.   http://www.firmfeel.com/ssk_b.html

Reinforced LCA (or DIY)  http://www.firmfeel.com/reinlca_b.htm

Frame connectors  http://store.uscartool.com/66-70-B-Body-frame-connectors.html

Torque boxes  http://store.uscartool.com/Torque-Boxes-Set-of-four-4-for-1966--1970-Mopar-B-Bodies_p_32.html



Lots of other great stuff from these vendors.

[dangina]

just FYI I used 1x3 tubing, clears the floor and I only had to tap with a hammer  just one spot by the rear pass footwell. Which is a plus seeing how some scca events don't allow welding to the floor pan, not sure what you plan to do with the car.

pics

[myk]

just FYI I used 1x3 tubing, clears the floor and I only had to tap with a hammer  just one spot by the rear pass footwell. Which is a plus seeing how some scca events don't allow welding to the floor pan, not sure what you plan to do with the car.

Seriously?  Did I just screw my car out of certain events with all of these suspension 'mods?

[fy469rtse]

No Myk .
thats why we are saying use the us car tool ones , done correctly and in the right hands , can look very factory, when you turn up to an event , ive found that unless you strike an expert on what came originally with every car , how would they know, thats the trick , make it look like it was always there , no shiny of flashy painted parts with stickers pointing out where and what company you bought it from , you dig 

[HPP]

...until you start winning and get protested and are found in violation.

IMO, if you are serious about racing in a specific class or sanctioning body, you should start with the rule book first. If you are just running for fun and don't plan to pursue it seriously, then you can probably get away with any number of mods.

[WHITE AND RED 69]

Torque boxes & subframe connectors are probably the biggest improvement. 

Some guys do HUGE subframe connectors, like 2x3 rectangular tubing, etc - it isn't necesary most of the time.   The SCs only need to be stiff enough so that area is not the weakest link in the chassis anymore, they don't need to be giant.   


Next is probably the lower radiator support bracing between the front rails.  The car needs this because the K-frame is not welded into place.

The shock towers are probably last after that.  But I would still do them.  IMO bracing the unibody is one of those things that doesn't really have a downside.  The cost isn't much, the stuff doesn't weigh a whole lot, and these days you can get the bracing from a catalog pre-shaped so you don't need to hack the car to install it.  In all the years I've been in this hobby, I cannot recall ever hearing anyone say they added SCs & torque boxes and couldn't feel a difference.

-------------------------------------

If you wanna stiffen up the feel some more, look into gusseting the K-frame itself.  The LCA mounting tubes can tear out of the walls of the K (metal fatigue).  And the steering box mount flexes even when the K-frame is brand new.  I can't remember off the top of my head but some company was selling braces to weld onto the steering box mount.

  Well said. Everyone always forgets about the radiator brace. I added the US car tool brace to mine and never realized how weak this area was until I was installing it. Even with the K-member bolted in I could see it flexing while I was drilling out the spot welds for the grill support bracket.

Be careful with mixing certain parts. Some sub frame connectors (like the hotchkis & PST) bolt onto the backside of the of the leaf spring mounts and the rear torque boxes will need to be modified. Still will fit but there is some cutting involved.

No matter which style or brand you go with you will definitely notice a huge difference. 

[fy469rtse]

You should post a link to that part of our thread for that radiator brace, I would like to see that as well, ! You've added this before or after paint , was wishing I had done this one also

[WHITE AND RED 69]

You should post a link to that part of our thread for that radiator brace, I would like to see that as well, ! You've added this before or after paint , was wishing I had done this one also

Did it way after paint was done. Just removed the radiator, drilled out the spot welds for the grill support bracket, sanded down the stock brace, some weld thru primer, the US car tool brace fits over the original, clamped it in place, and then welded it in.

[fy469rtse]

Great job, guess what I've ordered now to do once it arrives , now that I don't have to worry about paint issues
Valance has to come off for a repair anyway, don't ask  , was trying to get this car ready for show season , that's come and gone ,

[myk]

Hmm....Looks like this winter will see even more welding done to my car...

[MxRacer855]

Okay guys, you talked me into ordering a set of subframe connectors and a full set (4) of torque boxes from US Car a tool yesterday. I'm going to start with that. I'll post my progress/updates as they come!

Thanks!

-Jeff

[ottawamerc]

Good job Jeff its not a bad job to install them. Good luck and I know you will be impressed with the final results Just be careful and dont do what I did!
http://www.dodgecharger.com/forum/index.php?action=post;quote=1336496;topic=94375.925;num_replies=1065;sesc=6bc1fd056f21861b336f5970ecc7d565

Scott

[NHCharger]

I added sub frame connectors, body core stiffener and reenforcing plates on the LCA's. At the time I was just going to freshen the motor up. Ended up with a 500+ HP build by the time I was done. Now I wish I had added the torque boxes. On page 4 of my build thread you can see some pics
http://www.dodgecharger.com/forum/index.php/topic,95536.75.html