I know for us, when we build a 408 hyd. roller deal, pump gas, I have to make changes to the intake porting on the TF head if we want more than 540HP. Those changes allow 575+ at a real 10.6:1 compression! And the port doesn't really end up flowing much more air...you have to remember the QUALITY of airflow is what makes power...I don't give a **** if the port flows 280 or 310...but it has to make power.
