Bottom end is stock except for stronger main cap locating sleeves which have enough clearance designed in to allow use of 7/16 ARP studs. The main caps and girdle are OEM with minor mod's.
The crank is a pretty stout part, the main journals are 2.75" dia. and are cross drilled from GM. My guess is that GM looked at the 194/292 crank and decided to stiffen the 4200 to minimize harmonics. A couple of drag racers are spinning this engine to > 9000 RPM! Enough said.
Once I get back from the salt I'll put up more pix.
51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
