FYI, I weighted my KB and Mega blocks this weekend and there is 90lbs difference.

KB - 185lbs (4.360 bore)
Mega - 275lbs (4.5" bore & weighs 340lbs with crank and cam in it)

The Mega block is from Mopar from the mid 90's, no lightening and no concrete in it.

Wade Metzinger 918-809-0987
71 Cuda 9.28@145 -1s, Pglide
68 Cuda 10.64@124 1.45 60's 318->390 eddys
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