What are the "best" air lid, mass air, throttle body and intakes in terms of the highest HP gains?

 

Depends on what engines you are talking about.
Air lids fit on cars with LS1or 3.8. They add power because the stock unit restricts air flow.
Bigger MAF and throttle body will only add power when you have enough mods so that the stock unit is no longer able to meet engine air needs.

 

I am talking about adding these parts to motors who have the induction demand for them, i.e. motors that will gain power from larger cfm parts. What I am looking for is if anyone has seen dyno tests or actually swapped parts, stock vs aftermarket and aftermarket vs aftermarket. Basically I am looking for the manufacturers who sale items that gain the most HP for the price.

 

I'll pop up a vote for FAST, with their intake and 90mm TB people at least make a little power over the LS6 intake.