'65 Barracuda FS 273 4bbl 10.5 CR on pump gas in CA

'If you use I thicker gasket'

A 4.180 bore .046-.049 thickness #8553 permatorque felpro will take it down a substantial notch.

Unless you build a quench motor...knocking the timing out of it will ultimately reduce max output. 'One of those' doesn't want a lot of timing anyways.. right.