I have two ford small block circle track engines in the shop and measured the thread depth. the ford motorsports block is 2.00 and the Dart is 1.75.I would think in your application I would set the block up in a mill and drill the shallow holes out to get the same engagement as the others.most aluminum blocks are counter bored approximately .250 from the deck so the load is below the sleeve flange.With the power level your after I don't think you would be successful running a shallow bolt engagement and if it didn't work out and the holes were drilled deeper after the bores were finished i think you would have a bore distortion problem from the deeper engagement.Bill
not sure ont he depth of the deck holes,but if I remember right the threads were almost to the deck surface,but not sure,i dont have the block here with me,it started as a dry sump block that I found the right billet rear main cap to make it a wet sump,I have talked to GM racing and swart machine and the block can be converted to a wet sump block by drilling the approiate holes in a bridge port,I bought this block and now I gotta use it so I hope it holds up,I work at a performance and fabrication shop,and we have our own engine builer there and he keeps telling me I need to fill the block,but I really dont think it needs it,after looking it over it is a quite thick block,this is one of the best blocks GM makes as I was told by GM racing R&D department.
Dart and Brodix blocks have 1.500 thread engagement and need no helicoils.early G.M. blocks have .990 and in a high power application heli coils would help.Bill
06-12-2007, 04:18 PM
