Originally Posted by HDDP
a 75 mm inlet at 100 mph airflow would be 1673.91 ft3/min CFM
a 80 mm inlet at 100 mph airflow would be 1904.54 ft3/min CFM
Fueling would have to be increased by a minimum of 2 % otherwise a lean state would occur and no hp gain would be realized... Unless you can manipulate the ECU to reduce AFR from it's pre-programmed state of 14.7:1 you are wasting your time and money...
But if you are capable of adjusting the fueling and timing maps, then this will definately result in a minor HP gain...
I understand that the larger 80TB flows more air but I have my doubts about it's relevance, because the intake ports in the heads are really the restriction not the 75MM TB.
I can't find any dyno graphs from VRS, I will have to email him and see what he found. It could be he dosen't have the computer tuned to adjust for the extra incoming air.