I'm using a "406" block for the basis of my 428. It's a "62 HP" block and has the same std bore as the 428 4.13. It has the crossbolt bosses cast in, a
oil presure relief , solid lifters,larger
oil passages like the 427. The 406 was the forefather to the 427 and was only produced in 62 and early 63 and was the first block to be "crossbolted". I'm putting in a SCJ crank with lemans rods stroking it back to 428. As far as block metal I've learned from extensive conversations only some "race 428" blocks were made with a higher nickle content and the PI.CJ and SCJ blocks are pretty much the same. There is also an FE forum member making a cranksaddle support for the center maincaps.It is still in the development stage but in time after extensive testing will be put into porduction. G.
