What size engine for the online/Youtube EC?

I just consider myself a back yard idiot that has the minor benefit of at least having screwed together more than just a couple of engines and being blessed having been schooled by some smart people, a few racers and a couple of engineers in the field.

Truly my favorite thing is to just have fun and screw around seeing how stuff works. Swap cams just to see how it reacts, then swap intakes to see how they react, then swap carbs and so on.

It was the times before the internet that made it always fun experimenting since there were on 10,000 ways to make 400hp and everyone had a different way. Now you can science out with the calculators. Boring! But if you could only do it onceā€¦..