Ran across this on Inliners.org
Deck Height 11.156 228-236-248-256
Deck Height 11.250 256-270-302
I'm no GMC engine builder, but the numbers make sense except for the very rare 256 engine being shown with 2 different deck heights.
Given the 3/16" difference in stroke between the 228/248 and 270/302 engines and the fact that they all use the same rods, the deck height of the 228/248 would need to be 3/32" (0.09375") shorter than the 270/302.
Last edited by Bill Hanlon; 08/07/2025 3:17 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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