Frame or chassis options for A bodies
I really don't understand the bashing on magnum force being weak, that was the one thing I liked about their Transformer frame . It is very well built .Same with the lower control arms ,very well built. It is not something you want if your looking for a lightweight piece for a drag car. It weighs a lot more than a stock K.
Some people just flat out don't want a torsion bar stock setup , no matter how good they can be made to handle.
I am sure Andy the O.P. will find something aftermarket that he will be more than happy with.
I don't intend on getting into a heated debate about this, but since you asked:
I was referring mostly to the original style designs that left the rear control arm mount unsupported, just to flop around back there. I see the transformer has a tie bar back there and a double shear mount now, no doubt for that very reason.
At the end of the day that k-frame is a pretty poor design. There's no pilot to the frame as evidenced by the absolutely huge slots, so I am unsure how you actually ensure it doesn't move after it's installed. No doubt it's extremely difficult to install this in exactly the correct orientation.
The second issue is that unless I am not seeing something beefing up this area it has a pretty amazing stress riser in the areas circled in the attachment. Remember that lateral loads have to be transmitted back to the areas where the bolts are as there's only the clamp loads from the plate on that plane and the bolts transferring that energy to the car body.
It's basically a bunch of steel plates welded together except for in the area in front of the steering rack which is probably where it matters the least. Therefore it has to be much heavier than it would be if it was made out of tubing. Tubing in general is much stiffer than plate, especially to twisting. So the only way to compensate for that is to increase thickness massively. Not sure the wall thickness. I hope it's not something thin like 1/8".
This is also the same guy that sold kits for years where he'd hook coil-overs to the stock shock mounts without reinforcements. No doubt that those towers were not made to hold the car up.
I'm not sure any of the aftermarket coil-over k-frame kits are designs without some kind of fault. The alter-k-tion is probably a better design than this still but not really that rigid since it's only tied together with one square tube crossmember.
It would be interesting to see how these things deflect under shock loading from a pothole or whatnot.
The factory k-shape not only is resistant to to twisting in all directions, but the LCA is also partially supported by the torsion bar and torsion bar crossmember. So, suspension loads are spread out pretty well over the front of the car. They are also transmitting the forces from braking and acceleration on the lower control arms through the strut rods to a spot much closer to the front mounting bolt. It's pretty well done.
If you weld up the stock k-frame, gusset the steering box mounts and motor mount areas, beef up the LCA pin areas,and put the stiffening plates on the LCA, you've got a stiff platform. They also seem to hold up well even with the questionable welds.