How much power from intake swap?

I tried that same Indy tunnel ram on my 500" RB against an Indy single plane. The single plane was dyno'd with a 950HP and made 750 hp. The tunnel ram had dual quads, two 750HP's and it made 773 with minimal tuning. They made the same tq but the tunnel ram made it 600 rpm higher in the power band. The tunnel ram also made better average numbers from 3,500 - 7,000. I know it's not apples to apples to what you're doing but it's just what we learned when we experimented. Either way you will have a lot of interesting and usefull information when it's all said and done.