Curt, et al.,
I may have been the one that provided the 165-170 SCFM (at 28 " H2O, 0.500" lift). That estimate is based on information that a respected Inliner has told me, and semi-confirmed by a moderately-optimistic flow vs pressure drop analysis for the 235 head. Using a more pessimistic (but still defensible) analysis after looking at Curt's great photos, I can also predict a flow of 145 SCFM (at 28 " H2O, 0.500" lift). The flow path through the 848 head is not simple, with a tee and two 90-degree turns. That is why we need flow benches and CFD if we want real information. Also, the dynamic flow pattern is influence by the firing order, as cylinders 3 and 4 see a different valve timing than do 1-2 and 5-6.
If anyone would like to look at the Excel spreadsheet that I am using to calculate the flow numbers I could provide it in a PM.
I have not yet tried to analyze the exhaust flow. If I have nothing better to do I will attack it this weekend.
I hope that Curt gets the recognition he deserves for his work. It merits an article in the 12Port News, at least.
