LT 4 GM 1996 Chevy 12555690 Head
2.00 Intake & 1.55 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 | 34.7 | 39.7 | 14.3 | 70.3 |
| 0.100 | 68.8 | 82.3 | 19.6 | 70.7 |
| 0.200 | 134.6 | 148.6 | 10.4 | 70.2 |
| 0.300 | 184.2 | 193.1 | 4.8 | 74.8 |
| 0.400 | 218.4 | 231.7 | 6.1 | 74.6 |
| 0.450 | 231.7 | 255.5 | 10.3 | 70.1 |
| 0.500 | 240.7 | 261.5 | 8.6 | 72.2 |
| 0.550 | 237.7 | 267.4 | 12.5 | 73.0 |
Exhaust Port Test Results
Lift
Previous CFM Current CFM
% Gain Exhaust/Intake
| 0.050 | 22.2 | 27.9 | 25.5 | 70.3 |
| 0.100 | 53.4 | 58.1 | 9.0 | 70.7 |
| 0.200 | 98.7 | 104.2 | 5.7 | 70.2 |
| 0.300 | 125.2 | 144.4 | 15.4 | 74.8 |
| 0.400 | 142.8 | 172.8 | 21.0 | 74.6 |
| 0.450 | 150.9 | 179.2 | 18.8 | 70.1 |
| 0.500 | 155.7 | 188.8 | 21.3 | 72.2 |
| 0.550 | 159.7 | 195.2 | 22.2 | 73.0 |
Work done. Ported, flow tested, valve job, set up springs $805.00 4/01