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  • RX8 hitch - custom or not?

    2 main choices: Custom hitch or off-the-shelf.

    There are pictures of a custom RX8 hitch where receiver goes thru the rotary symbol out back. P.I.M.P.!!! I could make it... there's a trailer/hitch supply place in McKinney where I could get some of the stuff and I already have the main square tubing in my garage.

    http://www.vorshlag.com/fair/rx8/rx8_Hitch_1.jpg
    http://www.vorshlag.com/fair/rx8/rx8_Hitch_2.jpg
    http://www.vorshlag.com/fair/rx8/rx8_Hitch_3.jpg
    http://www.vorshlag.com/fair/rx8/rx8_Hitch_4.jpg
    http://www.vorshlag.com/fair/rx8/rx8_Hitch_5.jpg

    Guy said it took him ~2 hours to get the rear bumper off, but he was a n00b. He also removed the factory rear bumper (doofus!) and I wouldn't do that, of course. I'd sandwich it between the bumper and the frame mounts. I could also make it point downards for a completely hidden receiver (receiver would have a 90 degree bend in it to point back correctly when installed).

    The only 2 off-the-shelf sourced hitches are:

    Dalan hitch (from hitch-web.com):
    SKU #: 372816 , CLASS I RECEIVER, 1-1/4" Square Receiver with Ballmount, 25 pounds, $228.10



    Draw-Tite hitch (from Draw-Tite.com):
    p/n: DA247472, RECEIVER HITCH, 27.00 lbs, $187.02



    Ideas? These off-the-shelf units look COSTLY and the DA'LAN version had a lot of complaints about ripped trunk floors. The Draw-Tite unit doesn't look strong enough, but I can't find pictures of one installed yet. Both are pretty obtrusive looking.

    Note: I'd probably have to remove the stock exhaust to make room for the custom hitch - drat! Then I'd have to replace the muffler...
    Last edited by Fair!; 11-14-2005, 12:55 PM.
    Terry Fair - www.vorshlag.com
    2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
    EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

  • #2
    Re: RX8 hitch - custom or not?

    Originally posted by Fair!
    2 main choices: Custom hitch or off-the-shelf.


    Ideas? These off-the-shelf units look COSTLY and the DA'LAN version had a lot of complaints about ripped trunk floors.
    Is this a Fair-geration? Are you talking about Tommy or have you read that SEVERAL people have complained on RX-8's?

    I say buy off the shelf. You have too many projects.
    Brian Hanchey
    AST Suspension - USA

    Comment


    • #3
      Re: RX8 hitch - custom or not?

      I don't see how the RX8 could generate the torque needed to rip the trunk floor

      Seriously though, I agree with Hanchey. Spend time putting LS1s in E36s, not hitches on RX8s...
      Teucci has a good point about trannies - Tommy

      Comment


      • #4
        Re: RX8 hitch - custom or not?

        Just do like Dean and drive to the events on your Toyos

        Comment


        • #5
          Re: RX8 hitch - custom or not?

          Originally posted by hancheyb
          Is this a Fair-geration? Are you talking about Tommy or have you read that SEVERAL people have complained on RX-8's?

          I say buy off the shelf. You have too many projects.
          Bizzatch!

          No, this is really a common problem. Ripped trunk floors: http://www.rx8club.com/showthread.php?t=62703 DA'LAN had to reissue bigger reinforcement plates - but even with these plates, a trunk floor stamping is never a good place to put tongue weight from a hitch through.

          Also, the stock muffler interferes badly with the DA'LAN hitch, for one. See the same thread (and there's 3 more threadfs with similar stories).

          Have not seen a soul that has used the Draw-Tite, but it looks pretty cheesy - it just does away with the trunk reinforcement bars altogether, and uses the wimpy 2 bolts onto the bumper. Very under-engineered.

          Look, they make off-the-shelf hitches so that a monkey at a trailer place can install them in 15 minutes. This means they usually hang down low and attach to existing chassis holes. The only one with real user data (DA'LAN) isn't encouraging, and it looks clunky when installed.

          I think for someone willing to pull the rear bumper (and I've done this a lot lately - removing stock bumper covers) there could be a simpler yet stronger design that ties into the stock bumper-to-frame holes - with less overall weight and a more hidden/more pimpy design. I almost built one for the C6; we have actual race wheels on the way for the RX8 and a tire trailer sitting idle. I want to get something going before Spring racing season starts back up...

          Still could do off-the-shelf, but not at those prices. I have bought several hitches over the years and usually pay $100-150 for a Draw-Titie or U-Haul (even a C4 Corveete hitch was but $150 installed!). $187-228 is almost steep enough to make me want to build my own... almost.

          EDIT: F a bunch of Toyo nonsense!
          Terry Fair - www.vorshlag.com
          2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
          EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

          Comment


          • #6
            Build a Custom Trailer Hitch!

            Build a Custom Trailer Hitch - Part 1

            The plan was to build a custom, hidden trailer hitch for the RX8 with a receiver that protrudes through the "rotary" shaped symbol in the rear bumper cover. This would place the receiver higher than the Dylan or DrawTite hitch designs, not hanging so low that it might scrape the ground. In theory it would bolt to the factory steel bumper and be much lighter than the two mentioned above, as well as "muffler independent".

            I started this project Sunday Jan 15th and after 2 partial days of work I am still not done with it. What a whippin! I suspect I will have 25 hours of fab and design into this when I am finished. Yes, I should have paid $200-300 for a hitch and stuck it on there and lived with rattling and muffler interference. Oh well. I'm almost done and it will definitely be a one-of-a-kind.

            Here's some pictures from Day 1



            1. picture is of the receiver and hitch pieces I bought
            2. this is the hole in the rear bumper (that took 3 cutting/clean-up steps)
            3. rear bumper cover off (now that I figured that out I could do it in 20 minutes)
            4. beginnings of the fabricated bumper mount

            All of those 90 deg. bends are in 1/4" steel plate. I did this by sliding part of the plate into the vice and beating the hell out of the protruding end until it was at the angle I wanted. This requires a BIG hammer, lots os elbow grease and a sturdy vise and base. Of course this ruined both my arm and the vise base.

            The "design" of this hitch assembly has involved the attchment and removal of the bumper and rear bumper cover about 15 times to check alignment of the "rotary hole" and the receiver at each stage. Eats up lots of time.
            Last edited by Fair!; 01-22-2006, 11:45 PM.
            Terry Fair - www.vorshlag.com
            2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
            EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

            Comment


            • #7
              Re: RX8 hitch - custom or not?

              Build a Custom Trailer Hitch - Part 2

              Drilling through the hardened steel rear bumper assembly is a bizzatch! There are 3 complete thru-holes attaching the bumper mount. Each hole goes through 3 layers of steel, so it works out to 6 separa6te holes to drill. This steel is super hard - is has killed more than a dozen bits. I burned up three 1/2" bits trying to get thru the bumper in 2 steps (pilot hole + final diameter). I went and bought cutting fluid, an oiler and a 1/2" cobalt steel bit ($17 each!) and killed that one, too. At least it can be resharpened. Then I took my time and stepped the holes in 10+ steps, jumping up 3 bit sizes at a time from 1/8" to 1/2". That was a LOT of drilling and a HUGE mess. Then I had to drill through the steel mount for the same number of holes. Then I had to drill 4 holes to make the rounded corner hole for the receiver, before it can be welded on. I spent literally half of today drilling holes.

              More pictures, from Day 2:



              1. Clamped to vice and being welded.
              2. mocked up assembly with bumper on - perfectly aligned!
              3. this is where I ran out of welding wire. GRRR...
              4. it's getting complicated here.

              Coulda finished it tonight but it was after Lowe's had closed. Oh well, I am sick as a dog and need to get some sleep.

              Just remembered: I also spent several hours over those 3 "partial days" messing with other stuff: organizing bolts & nuts, several trips to Lowe's for supplies, welding the base and head of my Harbor Freight vise stand together (the cinch bolts had wobbled loose and never worked well; this took over an hour as I had to make 3 passes on each weld joining heavy cast steel pieces to thin-walled steel tubing), and setting up wireless LAN and laptop for garage tunes and podcasts (thanks to Jeremy for the podcast links to "This Week In Tech" and digg.com!) .
              Last edited by Fair!; 01-22-2006, 11:40 PM.
              Terry Fair - www.vorshlag.com
              2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
              EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

              Comment


              • #8
                Re: RX8 hitch - custom or not?

                Build a Custom Trailer Hitch - Part 3

                Some lessons learned:

                1. I need a fookin plasma cutter!!! Cutting 1/4" plate steel with a cut off wheel takes fookin forever.

                2. I needed larger pieces of steel plate on hand. The widest pieces I have (or have found for sale) are 6" wide x 10' long. This narrow selection prohibited me from making the bumper mount out of a single piece. This is why the upper two bent tabs and the lower receiver holder extension piece had to be welded onto the main assembly separately:



                3. I need to buy a set of GOOD drill bits. I have sets of "hardened steel" and "titanium" (coated) bits. These are just about worthless. The first set is OK for WOOD, the second is almost OK for carbon steel. Neither will drill thru hardened alloy steel. M2 tool steel or cobalt steel?

                4. I need to buy spare drill chuck keys. I must have lost each of my 3 (different sized) chuck keys for my 3 (different sized) drills 20 times each! ARG!!! I am pretty religious about putting tools away immediately after using them, too, but still kept losing stuff.

                5. Always have spare brake parts cleaner, welding wire, welding tips, bolts/nuts/washers, and lots and lots of steel in every shape and size. Each item listed was a trip to the hardware store...

                6. Never put the ground electrode for the welder onto anything above your head, nor onto a painted metal piece. It might burn thru the paint but it's gonna make a BIG spark. *POP!* "Sparks in mask, ahh!!!"

                7. Working in 40 degree rainy weather with the flu is stupid, stupid, stupid.

                8. Sometimes paying for pre-built parts is better than making them yourself.

                9. I either need 4 arms or a frakkin helper sometimes. I had to balance on one foot more times than I can count, using both hands and the other leg trying to align some of this stuff into the vise to clamp together. Amy usually is around to help in a pinch but she's been outta town for over a week.
                Last edited by Fair!; 01-22-2006, 10:43 PM.
                Terry Fair - www.vorshlag.com
                2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
                EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

                Comment


                • #9
                  Re: RX8 hitch - custom or not?

                  Finally finished up the RX8 hitch fabrication Tuesday night, but ran out of steam when I was putting the inner fender panels and trunk liners in around midnight. Finished that up in less than an hour Wednesday night. Whew! Amy helping on both nights really got me motivated, even when I was still sick as hell.



                  Too much mass (11.6 pounds) because of too much welding (I only had plate 6" wide), but it is way overbuilt and yet still "discrete". Definitely one-of-a-kind.

                  Now back to the E36 LS1...
                  Terry Fair - www.vorshlag.com
                  2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
                  EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

                  Comment


                  • #10
                    Re: RX8 hitch - custom or not?

                    Originally posted by Fair!
                    Too much mass (11.6 pounds) because of too much welding (I only had plate 6" wide), but it is way overbuilt and yet still "discrete". Definitely one-of-a-kind.
                    So, de-engineer it a bit, make a template and offer it custom-built for sale on the RX-8 boards. Could be Vorshlag's first real part in their ever expanding catalog!
                    '05 STi
                    Obfuscation usually requires a lot more words than if you simply focus on fundamental principles, so I’m not at all surprised by the loquaciousness of liberals.

                    Comment


                    • #11
                      Re: RX8 hitch - custom or not?

                      Looks good Terry. 11 pounds is pretty impressive too, the hitch for my car is like 30 pounds. =/
                      '11 Mustang GT / '95 Frankenpreza

                      "A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster."
                      - Dr. Clarkson

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                      • #12
                        Re: RX8 hitch - custom or not?

                        Originally posted by Oversteer
                        So, de-engineer it a bit, make a template and offer it custom-built for sale on the RX-8 boards. Could be Vorshlag's first real part in their ever expanding catalog!
                        The problem is that there's some pretty serious drilling involved. The bumper is hardened steel so just any old drill bit won't work. It would be tough for a DIY'er.
                        Brian Hanchey
                        AST Suspension - USA

                        Comment


                        • #13
                          Re: RX8 hitch - custom or not?

                          So how to the other RX-8 hitches attach?

                          BTW, nice job, Terry!

                          T
                          2001 Jeep Wrangler
                          2001 Dodge 2500 Cummins

                          BMW E36 DIY's:
                          Front LCA Bushing Swap
                          E36 Custom Cat Back
                          M3 Limited Slip Diff Repair
                          Diff Swap

                          Comment


                          • #14
                            Re: RX8 hitch - custom or not?

                            Originally posted by Oversteer
                            So, de-engineer it a bit, make a template and offer it custom-built for sale on the RX-8 boards. Could be Vorshlag's first real part in their ever expanding catalog!
                            Like Brian said, it involves a lot more than basic DIY skillz to install...

                            Here's the issues:

                            1. Removing the rear bumper cover. This entails removing 3 trunk liner panels, two rear fender liners, and both rear brake light assemblies. All told about 30 bolts and plastic rivets of 4-5 sizes. With good instructions (pictures and step-by-step) and patience a n00b could still do it.

                            2. Cutting out the rotary shaped hole in the bumper was time consuming, difficult, and could visually ruin the bumper if done wrong. More than n00b skillz and tools required. I used a drill (for corners), sheet metal air saw with a fine tooth blade (main cut-out), carbide rotary bit (for aluminum) in an air die grinder (for clean-up of edges) and a carpet cutting knife for final clean-up work. Took an hour or so and I've done similar work before...

                            3. Drilling through the alloy steel bumper structure completely in 3 places was a major, major wh0re of a job. I spent probably 8 hours (of the 25 hours of fabrication and design) drilling holes in the bumper. Stepping up in stages with LOTS of bit sizes and copious amounts of cutting fluid was the only successful procedure. Plus bit sharpening with a grinder (not possible with the Ti-coated bits). I destroyed over $50 in drill bits, maybe more. This hardened alloy steel bumper LAUGHED at standard "steel rated" black oxide coated bits (demolished 10+), it gobbled up two $17 Cobalt Steel bits and wasted several Titanium coated bits (two sets worth $50 total). I used one of David's "wood rated" bits and it turned it to goo. I would have thought it was made of plastic if I hadn't seen the glowing red slag coming off this bit!

                            4. If we included a pre-drilled factory RX8 bumper in the "kit" it might make it a lot easier - no drilling required. Remove bumper cover, bumper reinforcement (4 bolts), and install new bumper and hitch, pre-assembled. A real metal shop would need to pre-drill (with a fixture for proper hole alignment) the bumper reinforcement. Could have customers send their bumpers in on an exchange basis, with a large deposit. Hassles, hassles... and too few potential sales.

                            5. The main hitch fab wouldn't be easy as there is both curvature of the bumper it mounts to, tight tolerances to wrap around the bumper (or it would rattle), and tight tolerances between the hitch receiver and the "rotary hole" (or it would look stupid being offset in the hole) making for tight tolerances on everything else, too. Jigs and tight tolerances = money.

                            It seems like a lot of work and cost to make something that might never sell in big numbers, honestly.
                            Last edited by Fair!; 11-28-2007, 10:10 AM.
                            Terry Fair - www.vorshlag.com
                            2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
                            EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

                            Comment


                            • #15
                              Re: RX8 hitch - custom or not?

                              Originally posted by Tommy R
                              So how to the other RX-8 hitches attach?


                              The Dalan hitch (like the Draw Tite) mounts like cheese - two wimpy bolts to the frame and two thru the trunk floor. The trunk floor holes eventually rip out. Lots of people have complained and the newer kits come with large load spreading plates. Still, any large tongue weight loads (bike rack) would tear it all to hell eventually. Thin sheet metal is a crappy mount. 30+ pounds of added mass on the @ss.

                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0420.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0421.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0422.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0423.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0424.JPG - that's barely attached
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0428.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0432.JPG
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0437.JPG
                              http://www.vorshlag.com/fair/rx8/tra...IMG_0439-2.jpg
                              http://www.vorshlag.com/fair/rx8/tra...h/IMG_0440.JPG - frame mounting holes
                              http://www.vorshlag.com/fair/rx8/tra...IMG_0441-2.jpg
                              http://www.vorshlag.com/fair/rx8/tra...IMG_0442-2.jpg - death by bike rack
                              http://www.vorshlag.com/fair/rx8/tra...IMG_0444-2.jpg
                              http://www.vorshlag.com/fair/rx8/tra...IMG_0445-2.jpg


                              And see how low it all hangs? *SCRAPE* That's mostly why I didn't do an off-the-shelf hitch. Yuck!



                              The original guy's thru-hole custom hitch mounted in place of the factory bumper (not what I would call "Safe"):

                              http://www.vorshlag.com/fair/rx8/rx8_Hitch_1.jpg
                              http://www.vorshlag.com/fair/rx8/rx8_Hitch_2.jpg
                              http://www.vorshlag.com/fair/rx8/rx8_Hitch_3.jpg
                              http://www.vorshlag.com/fair/rx8/rx8_Hitch_4.jpg
                              http://www.vorshlag.com/fair/rx8/rx8_Hitch_5.jpg

                              Looking at it now, its pretty rough... Lots of angle iron, "Ray Charles" welds and it deletes the stock bumper (unsafe and not SCCA legal in almost any class/category, even SMOD). That design doesn't have any bends, no holes through the bumper reinforcement, and minimal welding; I could make somehting like that in 2-3 hours. Not the 30+ hours I spent making my SCCA legal, safer design.

                              After looking at the options I'm glad I did what I did, but I wouldn't want to do it again. Someone could offer me $500 to make one more like mnine and I'd say "hell no".
                              Last edited by Fair!; 11-28-2007, 10:14 AM.
                              Terry Fair - www.vorshlag.com
                              2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
                              EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

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