Gro Harlem said:
They actually told you that you would get 60whp gain from one of their heads? HAHAHAHA huge lies.
I had a gude head at one point.....the work wasn't particularly good. You are better off getting the same work done at a machine shop. And it would most likely cost less anyways.
60chp is possible in a larger motor. I have seen 50hp from a 2.6L Porsche engine after head work.
Having SAID that, none of these companies know what the hell they are doing. R&D on a single intak/exhaust head design can take a year, at least. My uncle, who races 911 air cooled, spent about 11K on his head, which pretty much amounted to finding the right cams and pistons, and sticking to them. Then, using putty/paste/paint in the head chamber and valve assembly to make miniscule changes to the head shape. Once you have your head flowed perfectly, you make a mold of it and create a new one, a process so damn complicated I dont even want to think about it. Im actually heading out this spring to work for the guy that did his head job.
Anyone that says "yeah, we've done somma them things" and charges a grand has not done sufficient R&D, or they have taken a precursory look at the head, made some "typical" changes, saw a small gain, and started marketing.
To reach peak gains from flowing takes a long time. And each time you make a change to one part (intake exhaust flow, intake/exhaust VALVE flow, chamber size and shape, etc) you have to redesign to some degree the other parts.
