You might want to ponder the dilemma of the bolts over stock siamese intake ports. Original BBC heads and intakes had the bolts. I used a C454 decades ago and it required the bolts. Most high flow aftermarket heads do not have those bolt provisions. If you install the C454 on a set of later heads, you'll most likely encounter a massive vacuum leak. You could weld up the holes and grind the intake to match, but it's quite a bit of work. Here's a link to an article I wrote for Summit Racing on that topic:
https://www.onallcylinders.com/2022/...n-a-1970-nova/
You can see more on my Nova build elsewhere on this site. It's a 565 cubic inch, short deck combination with Brodix BB3 Xtra heads. FYI, the Brodix dual plane is the only intake that fits under a flat hood and can fit aftermarket heads without the extra bolt hole. But it is for 4150 series carbs only. In my experience, 4500 Dominators can be a pain in the ass on a street driven car…
