[Adger Smith]

400 blocks are very touchy about the hone & plate procedure to get the bores right.
I agree with you Carl. I spend more time on 400 blocks than any other type of block that comes through my shop.
The procedure (if the pictures are right) for the hone job needs to change to get good ring seal. The studs need to be installed with the torque plate instead of bolts. There is a totally diffrent load put on the block with stud than bolts. You can see bore distortion and leakage in the original pictures of the bore. The distortion is all different down about 1/12 to 2 inches. Above that bolt and studs pull on the bore a different way. I can't tell if there is a gasket under the plate. For the best results they need to use the same type gasket that will be used when the engine is assembled. They are wasting time and effort to use a plate with bolts and then add studs when they do the assembly.
Might as well hone it with out a plate installed. You will get about the same results and leakage.