new old guy to site

I am building a 65 Comet straight axle Gasser to run with the Southeast Gassers . I am trying to decide whether to run a big small block or a small big block.

How about a Big big block??

Think about lbs per cubic inch. 521 in, times 8.0 equals a 4168 lbs. Sounds like a parts breaker to me. 435 cubes is only 3480.
Going be hard to get a 65 Comet to weigh over 3500 lbs after it is gutted and straight axle. The motor can be set back 10% of the wheelbase.

welcome to the site !!!!