TheInspiredFool
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Numbers are in. These are the 28"H2O numbers of depression for both intake and exhaust. I will swap my set-up to blow through from combustion chamber side out the exhaust later for proper exhaust numbers later. The intake flows 16.40cfm @ .100" lift and 22.46cfm @ .261" lift at 10"H20 for those of you who appreciate the 10"h2o at .100" and max valve lift numbers. I need to tighten up the exhaust port some but I knew that before I flowed the head. I am working on the proper exit angle and position but will be tightening it up soon. You can see that the intake port levels out at about 36cfm between .175" to max lift at .261". The port velocity will ramp up if the piston speed increases so the velocity will be higher even though the max cfm maxes out at 36cfm but it will be at a point where the piston is slowing down so there should not get close to sonic choke.
Note: I made a Helgesen calibration plate and calibrated using the 20cfm and 30cfm holes. My setting is based off from flowing 27.25cfm on the 30cfm and 18.80 on the 20cfm just to give some room for error so that I wasn't too far over since my numbers seemed high.
INTAKE @ -28"H2O:
Valve Lift CFM
.012 6.35
.025 9.45
.050 15.10
.075 19.00
.100 26.45
.125 31.60
.150 34.25
.175 35.90
.200 36.15
.225 36.50
.250 36.80
.261 36.80
EXHAUST @ -28"H2O:
Valve Lift CFM
.050 13.80
.075 19.00
.100 23.55
.125 27.00
.150 29.30
.175 31.25
.200 31.80
.225 33.10
.250 34.50
.264 35.10
Note: I made a Helgesen calibration plate and calibrated using the 20cfm and 30cfm holes. My setting is based off from flowing 27.25cfm on the 30cfm and 18.80 on the 20cfm just to give some room for error so that I wasn't too far over since my numbers seemed high.
INTAKE @ -28"H2O:
Valve Lift CFM
.012 6.35
.025 9.45
.050 15.10
.075 19.00
.100 26.45
.125 31.60
.150 34.25
.175 35.90
.200 36.15
.225 36.50
.250 36.80
.261 36.80
EXHAUST @ -28"H2O:
Valve Lift CFM
.050 13.80
.075 19.00
.100 23.55
.125 27.00
.150 29.30
.175 31.25
.200 31.80
.225 33.10
.250 34.50
.264 35.10
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