I should have explained my postion a little better, but I was on my phone waiting for my car to warm up so I could leave work.
72, I fully agree that something like the LS or any newer engine will see significantly more gains due to an increase in intake pressure over our 40yr old heads. Without reading what Mike did, I do not agree with his number or 3psi increase with just adding a couple inches to the runners. What I do know, is that there will be a sweet spot that will have a beneficial change based off your runner length, flange porting, air horn shape (if youre running them), plenum volume (which most arent running with this setup), etc. I doubt you will see 30hp change, but I would estimate you could easily see 5hp.
I do agree with your point that just changing intakes on cars can dramatically change their intake efficiency; I have seen it hundreds of times first hand. Many cars gain about 5-6hp by just changing from the stock airbox to a short ram intake and even more if using a true cold air intake. Ive even seen double digit increases just by getting rid of the stock crap airbox.
I would have to look at Mikes data to see where hes getting his numbers. Im sure I can still pull a few free ponies out of thin air (pun intended) by changing up my design.