hi
i didnt do this as a miracle cure just thought it would help ,it wasn't to compete with or upset, anyone else that has or is going to do this ,i dont think anything you do to the standard block is going to make it bullet proof there will always be issues with something that was never designed to make 800/1000 bhp.charlie shaw sent me pics of his block with ag sump and it had crack the block at the rear ,so even doing that way isn't guaranteed ,it seems to be vibration ,harmonics thats causing the block to crack always at the rear,has anyone looked at the possibility that it could be something to do with the input shaft or rear bearing that is causing the vibration problem ,it is a very small bearing in the rear of the crank ,might be worth machining and fitting a bigger better tolerance bearing ,also worth clocking the bell housing making sure input is actually running true to crank ,i am no expert just my hobby making these parts all done off my own back

thanks mark