[EfficiencyLover]

It may be useful for you to investigate using the Comp Cams Cam Quest program (free online) to learn about tweaking cam fitment for maximizing low and mid-range torque production. If you haven't already used this program, you'll see why it's being suggested. It can help with component selection. The GM TPI manifold is a gem for torque production. The second thought is using Total Seal zero gap rings. Give them a call and learn from people who can give experience-based advice on this area of efficiency - and longevity. The third thing is considering the use of Rhoads lifters on the intake side of your valvetrain. You will probably end up using a dual pattern cam, to compensate for the exhaust port's weaker flow (on Chevy small blocks' heads), so as a simple substitute for variable valve timing, you might find this useful. Just be aware of compression ratio/valve timing issues. Perhaps that is why you want to use the higher octane fuel. That may not be necessary - and you may not be so geographically limited by its availability - if you select your hardware combination carefully and keep a tight quench dimension. The people who race and develop engines are pursuing the same basic goal that you are - efficiency. They are usually not so concerned with longevity. :-) You can still use what helps you to achieve your goals and disregard the aspects that don't. This sounds like a worthwhile and fun project. Good luck with it.