Beginner Question: How to tell 273LA from 318?

toolmanmike said

Very observant. I finally got off my phone and onto a larger screen. It looks like the bolt heads are at a right angle to the head surface. If that is the case, it has a non-original engine, a 66 or newer 273or a 318. A good engine whichever one you have.

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Not to split hairs or argue, but the later small blocks did not have right angle bolt holes to the intake face. They are closer than the earlier 273s, but not at 90*. I thought they were too, but there was a thread on here......I think it had to do with that intake jig they were shipping around for guys to drill their heads to the Magnum pattern that that was discovered.