Ok let me put it this way, If you have a big motor say 512ci and you put a std port head on it thats somewhat restrictive which is what we will have in my opinion how do you make 650>700 on pump. Its either big comp/big s/roller and rpm. None of those will be there with a max of 11:1, and 3.91 gears apart from a big cam, have I answered my own question?.....
On my 440, I had a big sft cam with restrictive stock 906 heads, put same but ported BV heads on it and it picked up .5 and 6mph with no other changes, thats understandable, this build won't have the option of a better head, at least not for now so if there is around a 50hp difference if not more from his std. port 300cfm head to an MW head@350cfm+ as I see it how would you compensate for that given the comp and rpm limits of this build or is it impossible because at the end of the day the heads and intake system are where the power is.
You take those heads, and have them opened to MW size....And fill in the holes with JB weld....That's what's on our Dart..906's I think, with a 2.14/1.81 valves...Runs 10.76....
