If the head is the choke point (which it probably is) then it makes sense that the tunnel ram didn't help any. I've thrown a lot of different parts at these heads and basically they make what they make. The most cost effective combo is a solid roller plus the Trick Flow intake and a big 4150 carb. That setup gets you really close to 700 hp without breaking the bank. The tunnel ram might work better depending on the gears and converter but it doesn't make more peak power.