Sub frame connectors

Discussion in 'Suspension, Steering and Chassis' started by Shorty Thompson, Apr 22, 2018.

  1. Shorty Thompson

    Shorty Thompson Active Member

    Messages:
    39
    Likes Received:
    7
    Joined:
    Oct 17, 2009
    Local Time:
    7:22 AM
    Who got the best place to get some from ?
     
  2. TrailBeast

    TrailBeast Slightly Twisted Member

    Messages:
    18,045
    Likes Received:
    4197
    Joined:
    Mar 11, 2011
    Location:
    Arizona
    View My Photos
    Local Time:
    5:22 AM
    • Agree Agree x 3
    • Like Like x 1
    • Steven190

      Steven190 FABO Gold Member FABO Gold Member

      Messages:
      489
      Likes Received:
      159
      Joined:
      Jan 13, 2012
      Location:
      Omaha
      Local Time:
      7:22 AM
      US Tools has a great set and all the stuff to stiffen up the frame
       
      • Like Like x 2
      • Agree Agree x 1
      • jtkaaa07

        jtkaaa07 BossMan FABO Gold Member

        Messages:
        1,805
        Likes Received:
        372
        Joined:
        Oct 25, 2010
        Location:
        Neenah Wisconsin
        View My Photos
        Local Time:
        7:22 AM
        • Like Like x 2
        • Agree Agree x 2
        • supertruck

          supertruck Retired Old Fart stock car racer FABO Gold Member

          Messages:
          280
          Likes Received:
          91
          Joined:
          Feb 14, 2016
          Location:
          Gloucester, Va
          Local Time:
          8:22 AM
          OP probably already knows, but they are not a "fit and weld first time" deal. If you do it yourself, be prepared to do some trimming to meet the contour of the floor pans and install them multiple times. Worth it, though.
           
          • Like Like x 1
          • Agree Agree x 1
          • Shorty Thompson

            Shorty Thompson Active Member

            Messages:
            39
            Likes Received:
            7
            Joined:
            Oct 17, 2009
            Local Time:
            7:22 AM
            Looking at every post . Thank you so much
             
          • TrailBeast

            TrailBeast Slightly Twisted Member

            Messages:
            18,045
            Likes Received:
            4197
            Joined:
            Mar 11, 2011
            Location:
            Arizona
            View My Photos
            Local Time:
            5:22 AM
            I was talking about the home made type that don't weld to the floor OR the prefabbed ones that do.
            My Brother and I made mine with .085 wall 2x3 box steel that are not welded to the floor.
            The 1x little baby bolt in type I don't care for.
            Here's what we did that cost about 50 bucks and took a couple of hours.

            subframe.jpg
             
            • Like Like x 5
            • 1969VADart

              1969VADart FABO Gold Member FABO Gold Member

              Messages:
              2,003
              Likes Received:
              335
              Joined:
              Aug 19, 2013
              Location:
              Fredericksburg, VA
              Local Time:
              8:22 AM
              I welded the US Car Tools kit in my Dart. You can certainly home build your own, but you won't find many much better than what US Car Tool sells.
               
              • Agree Agree x 4
              • Like Like x 1
              • MRGTX

                MRGTX Well-Known Member

                Messages:
                1,327
                Likes Received:
                394
                Joined:
                Sep 24, 2007
                Local Time:
                7:22 AM
                Has anyone tried to measure the improvement from subframe connectors? I get that intuitively, thicker tubes and designs that follow the floor would be stronger but how do we know if lighter pieces might not do the job well enough?
                 
                • Like Like x 1
                • Jimacuda

                  Jimacuda Well-Known Member

                  Messages:
                  1,062
                  Likes Received:
                  201
                  Joined:
                  Nov 10, 2006
                  Location:
                  Phoenix AZ
                  Local Time:
                  5:22 AM
                  How light?
                  We're not talking about much weight here, at worst 10-12' of 2x3 steel...

                  With more precise fitment and full welding the material could be lighter.

                  I slit my floors open to run the 2x3 from t-bar crossmember back stuffed into the rear frame rail as far as it would go. Fully welded in everywhere.

                  DSC07174.JPG
                   
                  • Like Like x 2
                  • Jimacuda

                    Jimacuda Well-Known Member

                    Messages:
                    1,062
                    Likes Received:
                    201
                    Joined:
                    Nov 10, 2006
                    Location:
                    Phoenix AZ
                    Local Time:
                    5:22 AM
                    carpet layed down nice over them

                    100_1344.jpg
                     
                    • Like Like x 2
                    • Jim Lusk

                      Jim Lusk Well-Known Member

                      Messages:
                      3,733
                      Likes Received:
                      246
                      Joined:
                      Mar 8, 2006
                      Location:
                      Fresno, CA
                      View My Photos
                      Local Time:
                      5:22 AM
                      Beware that the US Car Tool require re-routing the brake and fuel lines and the park brake cable. Been working on a 1970 Charger that already had the connectors in, but none of the other parts. It's a real PITA...
                       
                      • Like Like x 1
                      • Agree Agree x 1
                      • 72bluNblu

                        72bluNblu FABO Gold Member FABO Gold Member

                        Messages:
                        8,287
                        Likes Received:
                        2282
                        Joined:
                        Nov 28, 2008
                        Location:
                        NorCal
                        Local Time:
                        5:22 AM
                        You’d literally need a full finite element analysis of the chassis and different connectors to figure that out. Comparing different installs on different 50 year old cars wouldn’t likely get you good information. Just a really large margin of error.

                        With the connectors something is better than nothing. Even the bolt in Mopar Performance connectors, welded in, make a difference. Eventually you reach a point where adding more wall thickness or tube diameter doesn’t matter, you’ve strengthened the chassis as much as you can with that single reinforcement.

                        I think the weld to floor US Cartool connectors probably look best, but they’re a royal pain to get fitted and fully welded to the floor if you’re not working on a media blasted chassis on a rotisserie. And you have to re-route all the lines. I used 1.5x3 tube with large landing plates on my Duster. They work great, fit flat to the floor and frame, and were a lot easier to install than the US Cartool connectors I installed on my Dart.
                         
                        • Like Like x 1
                        • Thanks! Thanks! x 1
                        • oi81b4uu812b4

                          oi81b4uu812b4 Well-Known Member

                          Messages:
                          135
                          Likes Received:
                          38
                          Joined:
                          Mar 7, 2016
                          Location:
                          Michigan
                          View My Photos
                          Local Time:
                          7:22 AM
                          I disagree. I've done US Car Tool stiffeners both ways rotisserie and on a hoist. The only trouble is getting undercoating off or not knowing how to remove it. Other than that it's just welding. The trouble area on sub frame connectors is not placing the weld on the US Car Tool sub frame connector and rolling the weld into the floor pan. Once you learn that, it's easy. Just takes time and a good welding jacket.
                           
                          Last edited: Jun 7, 2018
                          • Like Like x 2
                          • MRGTX

                            MRGTX Well-Known Member

                            Messages:
                            1,327
                            Likes Received:
                            394
                            Joined:
                            Sep 24, 2007
                            Local Time:
                            7:22 AM
                            I believe that you don't see this as a big deal...but (correct me if I'm wrong here) the trimming and adjusting to get these to fit perfectly along the floor pan then prepping/welding the entirety of the length is orders of magnitude more troublesome than bolt-in/weld-in options.

                            It certainly doesn't sound like rocket surgery but doing it right is time consuming and daunting to people who don't have welding experience, proper working space, extra time, etc.

                            Are these better? Most people seem to think so! They certainly look way better. Is the level of improvement over more accessible options proportional to the additional effort/expense? That's not a forgone conclusion, IMO.

                            If anyone wants to offer up their Mopar for me to practice on, come on over! :D
                             
                            • Like Like x 1
                            • Agree Agree x 1
                            • 72bluNblu

                              72bluNblu FABO Gold Member FABO Gold Member

                              Messages:
                              8,287
                              Likes Received:
                              2282
                              Joined:
                              Nov 28, 2008
                              Location:
                              NorCal
                              Local Time:
                              5:22 AM
                              Removing the undercoating is probably the easiest part of the whole deal. The USCT subframe connectors take a lot longer to install, and the welding is not easy, at least not in my opinion. I've been welding for over 25 years. I wouldn't consider myself an expert by any means, but I didn't pick up a torch yesterday. The welding that needs to be done definitely isn't the hardest I've done, but it's not something I would consider "easy" for an amateur welder. And there's a ton of it- you're conservatively talking about at least 15 linear feet of weld bead to fully weld them (at least on a 111" wheelbase car). And if you're working off of jackstands, it is a pain in the ass IMHO. Not everyone has a hoist, and not everyone is stripping their car and putting it on a rotisserie.

                              I've installed both types of frame connectors, and installing the tube style connectors is MUCH easier. Done in a few hours, no line re-routing, and depending on the size of the tube and landing plates very little undercoating removal.

                              I like the US Cartool connectors, they look a lot closer to factory and they're well made parts. But there is a big difference in the time and skill needed to install them compared to the tubular style connectors. I've done both, and after installing the USCT connectors on my Dart in my garage with the car up on 12 ton jackstands it's still my opinion that it was a pain in the ass, especially compared to a similar install of the tubular connectors on my Duster. That doesn't mean they aren't a good part, or that they shouldn't be used. It just means that a person should consider their skills and resources available when deciding what kind of connector they're going to install.

                              Exactly. They have their pros and cons. They do look better IMO, but they require a lot more time and work to install. Even the brake and fuel line re-routing is not something to just blow off, it takes some time to do it right and have it look good.

                              And whether or not they actually work better is not something that anyone here can know for sure, absent of some really complicated finite element analysis that no one is going to do.
                               
                              • Agree Agree x 2
                              • Like Like x 1
                              • Thanks! Thanks! x 1
                              • 68Dart500

                                68Dart500 Well-Known Member

                                Messages:
                                143
                                Likes Received:
                                99
                                Joined:
                                Oct 24, 2017
                                Location:
                                Somerset, WI
                                Local Time:
                                7:22 AM
                                I just bought 1.5x3 .125 rectangular tubing to make a set for my 68 Dodge Dart. I appreciate you posting the diagram as I'm doing a similar design. I am curious though, was your car a Dart Sport aka Demon? Unless the 73 Dart coupe body style really shortened up the underside my 2 door 68 Dart coupe (not a post car) needed 50 inch long pieces not 40~ inches.
                                 
                                • Like Like x 1
                                • TrailBeast

                                  TrailBeast Slightly Twisted Member

                                  Messages:
                                  18,045
                                  Likes Received:
                                  4197
                                  Joined:
                                  Mar 11, 2011
                                  Location:
                                  Arizona
                                  View My Photos
                                  Local Time:
                                  5:22 AM
                                  Dart Swinger hard top here.
                                   
                                  • Like Like x 1
                                  • marksmopar1

                                    marksmopar1 Well-Known Member

                                    Messages:
                                    604
                                    Likes Received:
                                    106
                                    Joined:
                                    Feb 21, 2014
                                    Location:
                                    Winnipeg, Canada
                                    Local Time:
                                    7:22 AM
                                    Convertibles and Big Block cars with the 4 torque boxes.....This is a little trickier at the rear to attach the frame connector.
                                    The US tool item works, but not what I want. I am looking at Chrome Molly round tubing, slight bend to follow the floor and incorporate the driveshaft loop. This is for my 69 Dart Convertible. Convertibles really benefit from the frame connectors. I figure round tubes place just right will allow emergency brake routing better.... any thoughts, anyone tried?
                                     
                                    • Like Like x 1
                                    • Jadaharabi

                                      Jadaharabi FABO Gold Member FABO Gold Member

                                      Messages:
                                      1,861
                                      Likes Received:
                                      1389
                                      Joined:
                                      Jan 8, 2016
                                      Location:
                                      Peoria, Illinois
                                      Local Time:
                                      7:22 AM
                                      Most round tube connector are doubble tubes so the second tube keeps the single tube from twisting.
                                       
                                      • Like Like x 2
                                      • Shorty Thompson

                                        Shorty Thompson Active Member

                                        Messages:
                                        39
                                        Likes Received:
                                        7
                                        Joined:
                                        Oct 17, 2009
                                        Local Time:
                                        7:22 AM
                                        Applause . applause , applause!!!! Very good replies folks. I'm no stranger to a mig welder. I own a 160 Century, 220v.. I also have many years welding lawn cart cart bodies as well. Meaning 16ga. , to 19ga. . So I'm no stranger to thin metal. Keep the comments coming ! I am very anxious to hear everyone's opinion.
                                         
                                      • 68Dart500

                                        68Dart500 Well-Known Member

                                        Messages:
                                        143
                                        Likes Received:
                                        99
                                        Joined:
                                        Oct 24, 2017
                                        Location:
                                        Somerset, WI
                                        Local Time:
                                        7:22 AM
                                        I ordered 51 inches which means about 6 1/2 inches will slide over the rear rear and the front it will but up against the torsion bar mount. I don't see how there is any possible way yours would be long enough at 40 3/4 inches total length. That doesn't even come close to being long enough. I wondered if you actually meant to type 50 3/4 instead of 40 3/4 on your diagram?
                                         
                                        • Like Like x 1
                                        • TrailBeast

                                          TrailBeast Slightly Twisted Member

                                          Messages:
                                          18,045
                                          Likes Received:
                                          4197
                                          Joined:
                                          Mar 11, 2011
                                          Location:
                                          Arizona
                                          View My Photos
                                          Local Time:
                                          5:22 AM
                                          Do not use the measurements in the image above as they are 10 inches short.
                                          Sorry for the mistake, and this image is correct.

                                          subframe.jpg
                                           
                                          Last edited: Jun 10, 2018
                                          • Like Like x 1
                                          • Thanks! Thanks! x 1
                                          • 68Dart500

                                            68Dart500 Well-Known Member

                                            Messages:
                                            143
                                            Likes Received:
                                            99
                                            Joined:
                                            Oct 24, 2017
                                            Location:
                                            Somerset, WI
                                            Local Time:
                                            7:22 AM
                                            Yeah my best guess is it must have been a typo because I think our cars unibody should be identical (2 door coupe Darts). I just would hate for someone to see that diagram and order based off the measurements if they are wrong lol. I almost did but thankfully I thought I better go measure mine just to be safe and that's why I ended up ordering 51 inches instead of 41 :).
                                             
                                            • Like Like x 1
                                            • TrailBeast

                                              TrailBeast Slightly Twisted Member

                                              Messages:
                                              18,045
                                              Likes Received:
                                              4197
                                              Joined:
                                              Mar 11, 2011
                                              Location:
                                              Arizona
                                              View My Photos
                                              Local Time:
                                              5:22 AM
                                              And you were correct, as I typed 40 3/4 when it should have been 50 3/4.
                                              Thanks for pointing that out so it could get fixed.
                                               
                                              • Like Like x 1