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    #31


    Originally posted by AussieE46M3 View Post

    The front brace may be able to fit with the old stage 2.5 kit in place as they were based on the same contours however, where the front brace bolts to the front subframe mounts would be an opening for a hollow tube and thus, nothing to bolt to nor a flat surface of sheet metal a blind fastener (rivnuts) could be added to mount the brace.
    I took another look at the old setup in the car. I see what you mean by hollow tubes and those connections/extensions from rear to front beams.

    For the front, you think it's possible to get a more future proof/generic brace with proper load paths if attachment points use the pivot point for the rear seats (the 4 holes circled in yellow), and/or the rear seat belt/supports for cushion (circled in red)?

    I can see the ones in yellow being easy to adapt and they are close to the right cup. The left attachment gets tricky with contour of the floor under the seat to get to the rear seat belt attachment points.

    What about threaded plates, that could be welded on or epoxy/riveted to the old front beam, ala what you provided for attaching the rear x brace to the beam (tsbk threaded mounting plates)?

    Sent from my SM-G950U using Tapatalk

    Youtube DIYs and more

    All jobs done as diy - clutch, rod bearings, rear subframe rebush, vanos, headers, cooling, suspension, etc.

    PM for help in NorCal. Have a lot of specialty tools - vanos, pilot bearing puller, bushing press kit, valve adjustment, fcab, wheel bearing, engine support bar, etc.

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      #32
      Originally posted by mrgizmo04 View Post



      I took another look at the old setup in the car. I see what you mean by hollow tubes and those connections/extensions from rear to front beams.

      For the front, you think it's possible to get a more future proof/generic brace with proper load paths if attachment points use the pivot point for the rear seats (the 4 holes circled in yellow), and/or the rear seat belt/supports for cushion (circled in red)?

      I can see the ones in yellow being easy to adapt and they are close to the right cup. The left attachment gets tricky with contour of the floor under the seat to get to the rear seat belt attachment points.

      What about threaded plates, that could be welded on or epoxy/riveted to the old front beam, ala what you provided for attaching the rear x brace to the beam (tsbk threaded mounting plates)?

      Sent from my SM-G950U using Tapatalk
      That's a very real possibility although, getting a bit under there with some eccentricities so may no be ideal.

      A possible solution could be to drill holes in the front face of the RACP and fit a plate with clinch nuts on the back providing the female threads in the correct location for the front brace.

      It would be experimental but, that's likely the easiest way to make it work. I'll offer what help I can to make it work if you genuinely want to give it a go.

      Comment


        #33
        What combination of these would work with a Vinc÷bar? The front brace for sure but the rear bolt in brace as well?
        Instagram: @logicalconclusion

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          #34
          Originally posted by EthanolTurbo View Post
          What combination of these would work with a Vinc÷bar? The front brace for sure but the rear bolt in brace as well?
          If you did some custom fab, you could make the rear brace work I'd imagine.

          The front brace wont work as his uses open tubes. I'd remove his front kit and install ours as it spans the full RACP and ties into the frame rails so there is something to gain by upgrading and then add the brace rather than trying to modify it to work.

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            #35
            Here's a question I don't think has been answered before:

            If one adopts the complete upper bracing structure (front+rear topside reinforcement), is there actually any need to do lower plates? Assuming you have a solid floor pan to start with, I can imagine you remove the need to correct a roll center (as plates require) because the load path issues have been solved. Just throwing a thought out there, though I'm happy to be proven wrong.
            2002 M3 Coupe | 1988 320i Touring

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              #36
              Originally posted by Albino09 View Post
              Here's a question I don't think has been answered before:

              If one adopts the complete upper bracing structure (front+rear topside reinforcement), is there actually any need to do lower plates? Assuming you have a solid floor pan to start with, I can imagine you remove the need to correct a roll center (as plates require) because the load path issues have been solved. Just throwing a thought out there, though I'm happy to be proven wrong.
              A member from m3f, CCE46M3, determined this in his write up years ago.

              Comment


                #37
                Originally posted by Albino09 View Post
                Here's a question I don't think has been answered before:

                If one adopts the complete upper bracing structure (front+rear topside reinforcement), is there actually any need to do lower plates? Assuming you have a solid floor pan to start with, I can imagine you remove the need to correct a roll center (as plates require) because the load path issues have been solved. Just throwing a thought out there, though I'm happy to be proven wrong.
                This is something I've been asked a few times. The short version is I think the rear two RACP mounts are fine, I'd still be concerned about the front two. If you plate the front two you need to plate the rear two so the subframe is spaced evenly.

                The roll centre correction in the subframe bushings I offer isn't to compensate for the plates (although it helps) it's to just improve geometry when you lower the car. I do the same on E36, E9X etc. I even have something to correct the roll centre & bump steer up front on E8XE9X and newer beamers. I'm experimenting with it in my E92 M3.

                The longer version is that, in theory if you had a new floor and did that level of topside reinforcement with solid subframe bushings (or any bushing that sits on the hex stud rather against the underside of the chassis, I suspect you would be in the clear.
                My only concern is the front two, rear subframe mounts. the front two studs experience a lot of driveline force as point loads due to the lack of eccentricity to the driveline and also support the vast majority of cornering force as the arms are much closer to the front than rear.
                I would be concerned that the front two mounts would still crack on the underside of the car due to those forces based on first hand experience repairing them.

                If the car is anything less than brand new then underside plates are necessary to repair & compensate for the fatigue in the original sheet metal. As these cars get older the state of the RACP seems to be worse every time I inspect them so larger and more substantial plates are becoming ever more necessary. I suspect this is why a lot of the big brands have updated their designs (e.g. Turner).

                Comment


                  #38
                  I just wanted to do a separate comment on something a little off topic for this thread for those that have shown interest in the products as I'd be interested in getting your feedback on something.

                  I've had a wacky idea I haven't been able to get out of my head and would like to know, if I went to the trouble, would anyone actually want it? I'll likely do it for myself eventually however, could prioritise it higher if there was public interest.

                  I have come up with a concept that would only require some basic modifications and a few extra parts to my existing rear RACP bolt in brace structure (linked below for reference) to mount cantilever/pushrod rear suspension.

                  https://cmpautoengineering.com/colle...-bolt-in-brace

                  I am not a race car driver who needs the additional complexity for performance reasons, I just like geeking out and designing something unique and to challenge myself. If it becomes a one off just for myself I would still be happy to share progress with the community here.

                  Essentially I could design some rods, brackets, plates and pivots that could then be fitted to the existing product to accommodate generic shocks & springs depending on your preferred source and where you are in the world.

                  The benefits being greater wheel clearance, reduced un-sprung mass and depending on how the pivots are designed and the rod length used, variable (climbing) spring/damper rate through travel meaning, it's soft for small bumps and climbs to a stiffer spring rate on bigger bumps.

                  It wont be this year or likely anytime too soon however, it feels like something I'll inevitably do regardless.

                  Look forward to hearing thoughts.


                  Last edited by AussieE46M3; 12-06-2022, 03:41 PM.

                  Comment


                    #39
                    AussieE46M3 no one here unwarrants creativity and design. Especially if there could be a use case. I say design it ultimately for you and share it to see what others will think. I'm a visual person so I personally would like to see renderings

                    Comment


                      #40
                      Originally posted by AussieE46M3 View Post
                      I have come up with a concept that would only require some basic modifications and a few extra parts to my existing rear RACP bolt in brace structure (linked below for reference) to mount cantilever/pushrod rear suspension.
                      I have no need for this, but it sounds awesome. Would love to (eventually) see renders/prototypes!
                      2002 Topasblau M3 - Coupe - 6MT - Karbonius CSL Airbox - MSS54HP Conversion - Kassel MAP - SSV1 - HJS - PCS Tune - Beisan - MK60 Swap - ZCP Rack - Nogaros - AutoSolutions - 996 Brembos - Slon - CMP - VinceBar - Koni - Eibach - BlueBus - Journal

                      2012 Alpinweiss 128i - Coupe - 6AT - Slicktop - Manual Seats - Daily - Journal

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                        #41
                        Does the "front mount" brace require cutting the metal above the front subframe mounts? It's not clear from the pictures how it braces them. Both the previous CMP design and Vince's solution require cutting to that area, if I recall correctly.


                        Is the front mount a weld in solution only or could it be epoxied?

                        Comment


                          #42
                          I'm glad to hear you guys find the idea stimulating like myself. I'll start the preliminary research and let you know when I have something to share!

                          Originally posted by Amos View Post
                          Does the "front mount" brace require cutting the metal above the front subframe mounts? It's not clear from the pictures how it braces them. Both the previous CMP design and Vince's solution require cutting to that area, if I recall correctly.


                          Is the front mount a weld in solution only or could it be epoxied?
                          The front 'brace' does not require any cutting of steel. It does require 1 hole drilled either side for it to be mounted.

                          The front 'weld in beam' does require cutting to access the top of the front two RACP mounts. The process is well documented in the spiral bound instructions that come with the kit.

                          No, it cannot be epoxied in for a multitude of reasons.

                          Comment


                            #43
                            I'll be a buyer soon. As others have said, thanks for supporting the chassis still! Some really nice looking stuff!
                            Build thread: Topaz Blue to Shark Blue

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                              #44
                              Originally posted by AussieE46M3 View Post
                              I'm glad to hear you guys find the idea stimulating like myself. I'll start the preliminary research and let you know when I have something to share!



                              The front 'brace' does not require any cutting of steel. It does require 1 hole drilled either side for it to be mounted.

                              The front 'weld in beam' does require cutting to access the top of the front two RACP mounts. The process is well documented in the spiral bound instructions that come with the kit.

                              No, it cannot be epoxied in for a multitude of reasons.
                              Thanks for the response, I will probably be putting an order in after Xmas. I already have the Mason brace for the rear mounts and this front "weld in beam" looks like the easiest and best looking solution for the front mounts.

                              Comment


                                #45
                                to piggy back off CMP and Albino09, I think you would have to completely remove all the seam sealer and undercoat of the RACP in order to fully verify that the RACP does not have any failed spot welds. Hence why anything less than brand new would not be ideal. I've removed the seam sealer on my e46 m3 only to find failed spot welds where you would otherwise never know.

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