Doing some piston/rod mockups on paper to start out with & was wondering if alot of virgin/unmachined 70's 360 blocks tend to be above or below the nominal 9.6" deck height? Thank you for your time.

So far I've yet to see ANY Chrysler block that wasn't taller than spec.Kind of like head CC's almost always greater than spec. I doubt if there's ever been a 10:1 engine that actually was a true 10:1 from the factory.

Alright, & how much taller have some of the SB's been that have crossed your path

The LA blocks tend to be 9.58 and up while the magnum blocks I've seen as low as 9.56. Magnums are (to my knowledge) always lower deck than the LA blocks. Also seen quite a difference side to side. Won't know until you get one and measure it.

My 360 LA block was about 9.615" at the front and 9.605" at the back of the drivers side, Passenger side was about as uneven, just reversed, 9.605 front, 9.615" rear.

Not 360s but I have 5 340 blocks and they range from
9.579 to 9.588 measured at the front of the block...
I have one that was cut to 9.500 which I just built

Thanks guys, that's exactly what I needed

my '73 block was squared and cut and after final machining is 9.5995. Not sure what it started at though!

I have to measure it again but I believe my 86 318 block is taller than 9.600.
R.