Early 273 intake problems
That is indeed a 64-65 intake. Put some hardened washers on it and call it a day. I ran a Performer on the 65 heads with washers and it never leaked. AS for the holes that dont line up, take all the bolts out and manually line up the intake again. I bet they all line up with 5/16 bolts. I got to question the wrench needed to tighten those '5/16' bolts. If its a 9/16 hex then they are 3/8 bolts. 5/16 take a 1/2 wrench as those head angles are 3/8 for sure. Whats head casting number?
2465315 – 1964-1965, 273 LA-series small-block, 1.78/1.50 valves
2532080 – 1964-1965, 273 LA-series small-block, 1.78/1.50 valves
My pic of a real deal 65 intake and 64 heads, note skinny 5/16 bolt face angles and casting line on head that follows bolt angle. 66+ heads are at a 90 to the intake face. Check your head(s)for this line, buck says they don't have 'em.