[b-man]

You definitely need to find a 1964 intake.

That old intake you have matches up to inferior early heads that were on engines that had a lot of differences I don’t want to get into.

Suffice it to say you’re going to need a 1964 intake, assuming the engine is still a 1964. By now a lot of them have later engines and heads that only fit 1965 and up intakes so make sure what heads you have. You can identify the heads by the casting numbers on the two center exhaust ports.

1964 GTO engines all came with 9770716 heads, pictured below.

After 1964 the intake manifold bolt pattern and water crossover design changed. 1961 - 1964 intakes will interchange however only 1964 intakes had a high rise design, they are unique.