SOHC EJ25 head flow

[shazapple]

Grabbed this from nasioc. Figured it would be some interesting info here
http://forums.nasioc.com/forums/showthread.php?t=880185

Stockish numbers (unreliable)


Lift Intake Exhaust
.100" 84CFM 90CFM
.200" 169CFM 155CFM
.300" 235CFM 190CFM
.400" 247CFM 199CFM
.500" 247CFM 201CFM


after a valve job (probably closer to stock then above numbers)


lift intake exhaust (short port) exhaust (long port)
.050" 35.0 29.5 31.3
.100 76.2 58.4 67.3
.150 121.6 101.7 105.1
.200 142.0 144.7 136.2
.250 162.3 184.0 153.9
.300 223.8 203.9 161.1
.350 240.3 209.2 163.1
.400 250.0 212.2 163.6
.450 255.5 215.7 163.5
.500 255.7 216.2 162.0


preliminary results


lift intake exhaust (short port) exhaust (long port)
.050 36.4 32.4 32.0
.100 78.3 69.0 57.0
.150 123.4 103.2 97.6
.200 162.9 146.9 135.8
.250 201.1 192.1 177.4
.300 234.3 225.7 192.3
.350 247.3 247.0 198.3
.400 256.0 258.8 202.2
.450 264.0 264.1 205.0
.500 265.7 267.0 208.0


Quite an increase in exaust flow the higher the lift!

[Qman]

The numbers are very accurate. However, the lift is an issue. The cams do not get that high on lift. Usually you'll see around .400" of lift. We did a set of heads that we had ported as well. We hit around 271cfm @ .400" lift. The porter stated no loss of velocity at these numbers. We then designed a cam to match. It has yet to be verified as the car is still being built.