As there are plenty of oil brands, what is the suggested brand for muscle cars.

As for oil filters is it true that for muscle cars you want at least 98% single pass effeciency.  

My personal favorite, and this just my opinion, others may not agree, is Shell 15w40 Rotella T diesel truck oil. It has all of the extreme pressure anti-wear additives that are missing from most automotive grade oils today, the reason they are missing is because of emission requirements and the fact that most engines today have a roller valve train. But for flat tappet camshafts, either solid or hydraulic lifter, you need the extra protection. COMP Cams recommends it as well as certain additives, you can find more info on their website. I'm a diesel truck mechanic and it is the choice of most Owner/Operators who want full life from their engines, as opposed to most fleets that turn over their truck inventory every 2 or 3 years and try to stretch their oil drain intervals to save money. I use Rotella in my Safari van 4.3L V6 and my 79 Formula (75 350), and it also available in a synthetic formulation. Just my two cents!
Steve