I have my dad's Superflow air bench in my basement, and have flowed a number of heads using it over the years. I have not had a 235 head on it, but have had 250's and lots of Pontiac's. I am a little surprised to see the operator had 3.5 cfm flow with the valves closed ( .000" lift ) on both intake and exhaust when doing the final check. That shows a leak in the machine or the head somewhere. 3.5 cfm is enough sway the results through out the whole range of lift. I left a sparkplug out once after days of porting, though I had done a really great job, it made a huge difference, and once installed my porting wasn't nearly what I thought it was. The changes made to your head will likely not hurt any of the performance, the change is minimal when looking at flow numbers and the higher lift numbers should help some when you get out to the passing lane. What I really don't like is the second and third pages with all the " calculated " numbers from the computer program from Performance Trends. PT makes really good programs, dad and I have used them for years, but what you have are based on a AMC engine with your numbers plugged in to it. Not that any of the numbers really matter or that you could change any of it, just be aware. The only thing you need to look at is the actual before and after. Flow benches are like dynamometers, each is different and each operator is different. My heads won't flow the same on two different days, let alone two different machines. There are correction factors that need to be set in place everyday, air pressure, altitude, humidity, all can change flow rates, even machine temperature can change numbers. When flowing 250 cfm heads, I have to stop and cool the machine down between lift ranges or the numbers fall, hot air doesn't flow as well as cooler air. Post some pictures when you get the head, and remember this, way back when when racing started, nobody had test equipment, most all of it was done in back garages by guys just like us trying something NEW.
Last edited by Joe H; 08/29/2022 2:43 AM.
