Cab, Yes that would be great, just to the nearest 1/16" or so, it's to compare to the low deck blocks.

I measure one cylinder on each side of the 1971 block, I can't get a accurate measurement due to the dial calipers not fitting well in the cylinders but it looks like between 6.7 and 6.8 on the length of the cylinder walls on that block.
I have to take the heads off of the 1970 block later this afternoon and I should be able to measure it better on the engine stand instead of on a wooden dolly like the 1971 block is on now
I don't remember the differences in the low deck and RB block deck heights but it should be available on here some where
Don't forget about the main bore size differences also

The 1970 block #8 cylinder on the motor mount side looks like 6.755 long from top of the block to the bottom of the cylinder wall. I think this block is stock, the 1971 motor had a aftermarket timing set and a set of -.010 rod and main bearings in it so who know on the deck heights
IHTHs, back to watching drag racing in TX

Cab, Thanks ! Big help.

So 10.725 - 6.755 = 3.97, this is the radius of the crankbox so the crank counterweights would have to be less than 7.94" diameter.
And they are, 440 counterweights are 7.500 diameter.

3.97 compares to 3.75 on a 383 block.

So most of the increased deck height on a 440 goes toward a longer bore length.
The crankbox radius on a 440 is less than 1/4" bigger than the 383.

Long ago I came across an aftermarket billet crank that would not fit in a 440 block, the counterweights hit.
I can only wonder what block it came out of.

Probably a after market top fuel aluminum block, Milidon , TFX, KB or ?
Seems to me that they used long stroke cranks along time ago

It's been a while since I've built a stroked low deck , but IIRC it was not so much counterweight to block clearance as counterweight to piston pin boss clearance.

HTH
Randy

That depends on the rod length and the piston design.

Quite true. Built 12+ yrs. ago. KB 215 @ 1.722 CH and a 6.358 rod.

Randy

A 6.70 inch Chevy rod keeps the piston away from the crank and shaves a bunch of weight off the piston.

Yes, but stroker pistons and stroker cranks were not shelf items back in the late 80's and early 90's when I started that project. Typical kid with big ambitions, dreams of powerful engines, and little money. Arias Pistons was the custom piston to get. May as well have been a million dollars. Unattainable at less than
$1000 a month income. TRW slugs worked out really well for $100 and I had access to a milling machine. Crank was more than I anticipated. Took a couple of years to get it together back then. I cut the pistons in 86 or 87. Crank in was done in 90 or 91.

OK, I just counted. 12 sticks of Mallory, of different diameters.

OK, OK, I just measured. Counterweight diameter 6.874" on a factory 69 440 forged crank. Needed to clear the short 383 rods. Never occurred to me to run a 440 rod. It all works. Unconventional, but it works.

A 7.100 long BB Chevy type rod works even better on the 3.91 stroke and shorter motors

7.100 rod and 3.91 stroke won't fit in a low deck. There is no piston that thin, you would need a piston with a compression height of .92" I don't think you would even find one for 3.75 stroke and a 7.100 (1.002).