[DieselWrencher]

I'm still trying to figure out how a 12v block is prone to breaking at .020 over at any power level below at least 900hp? I've had many, many 12v blocks bored and haven't had any break. The engine in my vette is .040 and I put it in a tractor for a year and it's just fine. I know of a 12v block that was bored and put sleeves in it. It broke but that engine had catastrophic failure and the block shouldn't have been reused. I wouldn't be afraid of boring one for what you're doing.

Does your machine shop use a torque plate? They should if they make claims like this one about blocks breaking at .020.