Originally Posted by dgh938peg
I'm not sure on that one eazy. I cut down to the seam line of the subframe so there's about 30mm of meat left. When I cut that thing it did not move a single millimetre; which was pleasing to see! However I agree that removing half of the thickness will make it considerable weaker. I will be having some form of box section hoop over the gearbox so there would be plenty of stiffness to tie back into there..... From an engineers standpoint, it would make more sense to do it than not to!
Seems like I have talked myself into that one
I did mine the same way, cut down just to the top of the seam. Then reinforced the bottom of it from below the seam with some thick steel, and then did something similar to yours on top. I think with it built the way you have it, there should be enough strength, but a little extra is always nice too