Well this post from Mr. Jcisworthy started the ball rolling along a bumpy road at first but we got things smoothed out. The original problem here was who was going to cover the costs of dynoing the heads. But here Terry Walters stepped in and said 'while we are testing 6 sets of heads we may as well do 7 sets'. That's not only good for me but also ST forum members. While TW is helping us might be good to visit see if there is anything he might have to offer ST folk in the way of services and parts.jcisworthy wrote:So these heads are going to be dyno tested against stock heads? What about ported heads from someone else?
But that aside my main concern about testing someone else's heads was the possibility of getting a pair of lemons and all that would do was waste my time. As it happened I found, after a lengthy phone call, that I was dealing with a pro so I agreed we would go forward on this.
Let me remind you of the plot here. Our Mr.Jcisworthy wanted to establish whether or not a set of heads ported with the aid of my IOP flow bench program would be any better than a set ported by an experienced porter working to his own methods.
Well the heads arrived a few days ago and although they would not win any glamour contests, were well engineered. In short I liked what I saw.
At this point our intrepid head porter and I spoke over the phone, again at length. What I needed to do was to establish his line of thought that went into the architecture of this porting job.
Esentially it went like this. John (Mr.Jcisworthy) works along the lines of 'no metal removal unless the flow bench shows a measurable gain'. Before starting on the heads I now have, he ran through some trial ports on a spare head. From what I understand this was partly practice and partly to evaluate what the biggest useful intake valve would be.
Those who have followed this thread through may just remember I was intent on installing 2 inch valves and quite a few of the 'Fordy guys' said that there was little or no benefit from such a move. Guys you were right! The ported E7TE heads that I did with Charlie (carnut 1) ended up with 1.97 intakes and that may well be a little over the top at that. John's heads came to me with a 1.9/1.6 valve combo. Along with bronze guides it was also cut for studs and guide plates.
OK, at this point it was flow bench time. Unless the heads cut the mustard here there would be no dyno time. The first job was to take all the relevant dimensions and input into the IOP (Induction Optimized Porting) program. This entailed cc'ing the ports, measuring the port center line length, port widths, heights and so on. With all that done it was flow bench time.
Well so as to avoid any worry to the contrary let me say the results are good but will totally fail to establish whether or not the concepts of port energy are relevant or not.
I will explain why in my next post after I have done the artwork for such.
DV
