actually the 427 tripower (maybe 68?) made 435 and was well known to be underrated for insurance purposes. actually over 535 if I remember correctly (had one )
big blocks aren't normally meant for high rshared_pm use unless built as a dedicated high rshared_pm motor. A lot of my friends and my dad (circle track racer) all ran big block chevy's back in the day, I've also had a factory experimental 396 in a 70 chevelle, a 402 built by Zorians that used to be in our stock car before they dropped cubic inch limits that was put in our tow vehicle, and 4 big block vettes (2 427's and 2 454's).
sadly, I'm not the best educated when it comes to this, just from growing up with them. It took foxbody mustangs to drag me out of chevy's!

although I believe the termi block for a domestic probably the best to build from.