Cobra Jet Alm 460 Head
2.25 Intake & 1.760 Exhaust
Lift=Valve lift while testing Previous CFM=original flow
CurrentCFM=flow after porting % Gain=flow improvement in
percent
Exhaust/Intake=Relationship between intake & exhaust flow Flowed @
28 in.
Intake Port Test Results
Lift
Previous CFM Current CFM
% Gain Exhaust/Intake
| 0.050 | 50.3 | 49.6 | -1.4 | 69.0 |
| 0.100 | 88.2 | 82.3 | -6.8 | 80.4 |
| 0.200 | 143.6 | 142.6 | -0.7 | 85.5 |
| 0.300 | 199.1 | 202.0 | 1.5 | 87.1 |
| 0.400 | 254.0 | 264.4 | 4.1 | 76.2 |
| 0.500 | 291.2 | 317.1 | 8.9 | 72.6 |
| 0.600 | 308.2 | 348.4 | 13.0 | 72.6 |
| 0.650 | 317.1 | 361.8 | 14.1 | 70.7 |
| 0.700 | 321.6 | 370.7 | 15.3 | 69.0 |
| 0.750 | 321.6 | 379.7 | 18.3 | 67.4 |
Exhaust Port Test Results
Lift
Previous CFM Current CFM
% Gain Exhaust/Intake
| 0.050 | 40.6 | 34.2 | -15.7 | 69.0 |
| 0.100 | 72.5 | 66.1 | -8.8 | 80.4 |
| 0.200 | 115.5 | 122.8 | 5.6 | 85.4 |
| 0.300 | 158.9 | 176.0 | 10.8 | 87.1 |
| 0.400 | 166.4 | 201.6 | 21.2 | 76.2 |
| 0.500 | 188.8 | 230.4 | 22.0 | 72.6 |
| 0.600 | 193.6 | 252.8 | 30.6 | 72.6 |
| 0.650 | 195.2 | 256.0 | 31.1 | 70.7 |
| 0.700 | 195.2 | 256.0 | 31.1 | 69.0 |
| 0.750 | 195.2 | 256.0 | 31.1 | 67.4 |
Work done. Ported, flow tested, Valve Job, Set up springs. $1133.00 04/01