Thanks for the quick reply Ted!

Have a question regarding BBC cylinder heads.
If someone wanted to visually represent an L72,L78 or LS6 build but use oval port heads ( with casting numbers available from 65-73) with the correct rectangular port intake and correct appearing vacuum secondary Holley for that particular car would that be OK ? ET would probably be in 12.50-12.00 range.
Example: a 1969 SS 396 that looks like an L78 under the hood but in reality is a 512 casting 454 w/290 casting oval ports,163 aluminum intake and a 3310 Holley.

Yes, as long as the intake/carb set up is correct for year and model as your example shows!
You couldnt do it for example to a 72 chevelle!
The intake and carb style always have to match the car its on!

Chris, i was just looking at some older posts we discussed here, and im not dure you realize there was a rule change since then which may help you or your buddys!

There are more heads available to use in order to help keep costs downand availability up!
Still no aftermarket stuff but more oem for each marque!

This may be helpfull to know!

Thanks Ted!!
I was aware of the rule change..but I wasn't 100% sure if the square port intake on oval port heads was acceptable.
Nice to know that it is!

Its not a performance gain but that verbage was removed anyway!

You cant use large heads on small intake but thats a matter of fitment!