273 and 318 the same block?

seabee said

Interesting subject. After checking piston prices I have considered boring out my 273 to a 318 for a cruiser. Know a guy on here that made a 340 out of a 273 and it has worked fine but this is not on a high performance build. I definitely don't want to toss my 273 heads that had so much work put into them.

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...this makes no sense because if you had the bore of a 318, you would want 318 heads to take advantage of the larger valve sizes. You;;d be wasting the work you put into the 273 heads (valves too small for your cylinder displacement), plus the work you put into the block. But, as previously noted, you cannot bore a 273 to 318. So it's a moot point.