I did a few things this weekend. Prepped all my laser cut parts for welding and the frame. Took everything down and then sanded it all with the d/a like the pros, I tend to get caught up in deadlines which makes the process more stressful and I don’t do my best work. Trying to step this up so I get a better end result.
So.. this is what I have traditionally called a mezzanine rear suspension, ironically myself and Scott both feel like that makes no sense but the market calls it that. If it was up to me it would be a rear pivoting horizontally mounted cantilever, or RPHMC.
What is going on here is we’ve taken a design that is not prevalent but is very useful for anyone trying to keep back seats, or anyone wanting to move the moment of inertia back to the bumper essentially. the implications of doing that are not fully understood just yet, I have ideas about it based on driving Scott’s rig previously but we knew the solid axle held it back. what’s also nice about this is the shock package is moved rearward, this also mitigates any leverage you would see if the shock was mounted in the traditional location of a trailing arm. Therefore the increase in weight as a result of that and the drop in ride height is totally eliminated. So if you pack gear or anything heavy like people in the weight changes are all relative vs being leveraged.
We use a gm 1500 front unit bearing for this, it could easily be changed over to a 4wd bearing and an anti sway bar could be equipped. We aren’t proposing this because the arm is 45 inches long and that would require a large bar, being 33 spline that didn’t seem possible or cost effective. I’ll be packaging a sway bar in this which I will show once I get further along.
The basic layout is the bearing and spacers to set the bearing out away from the frame the proper amount, along with allowing a 3.5od pipe to keep the spacing proper on the rear portion and also to take the torsional load so the frame does not have to, if you can imagine there is a huge about of load on that bearing. We have a frame plate at the back to help brace it and to help in locating it properly.
this will be getting 2.5 coilovers and 3.0 bypasses at some point. This should be plenty for what I’m going to do.
One point I didn’t touch on is the shock package will be up and out of the way and the shock will only cycle in one plane. There is no horizontal misalignment. Shaft bushings and shafts should last a lot longer as will the bodies because they will be out of the way of the elements. Roost off the rear tire will be mitigated by bodywork once it’s done and enclosed. Cooling will likely be assisted by some window scoops or similar.
