Originally posted by 383 chev
L.O.L L.O.L L.O.L build the 400 no replacement for displacement steve morris racing built my engine when i called there to see if they had a 4 bolt block he said that they are weaker oh YEAH i run IT ON THE STREET with no steam holes every1 has an opinion call the pros!!!???
Steve Morris is a very good engine builder and a very decent man.Here are couple things to think about.The engine was only made from 72-80.It is the only Chevy engine to use extra steam holes.If this was such a great idea why did'nt G.M. use it on any other engine?Why was there never any performance 400's offered from the factory?Why does'nt Dart,World products,Brodix,Donovon or any other aftermarket company offer the extra steam holes?The reason is it makes the block weaker and more prone to cracks.Like I said I have a bunch of these sitting around the shop with cracks in them and one has a hole big enough between numbers 3,5 cylinders you can through a golf ball threw it.The other ones have cracks down the lifter valley on the drivers side.Two of them have cracks between the freeze plugs.I had one crack on the dyno and it was a .030 over bore.The block was even sonic tested before the build and was (rocked) to the bottom of the freeze plugs.I have only had one 350 block break over the years and it was doing 603 h.p. on methanol and it was .060 over.Just ask yourself why did G.M. use the extra steam holes?Do you think there might have been an overheating problem from the factory because the walls where to thin and the coolant could not pass between the cylinders and this is why they decided to drill the extra steam holes to try and cool it down more?