In diesel performance, achieving optimal airflow is the cornerstone to unlocking your engine’s full potential. For owners of the 6.7L Cummins, upgrading the intake system is a popular and effective ...

but the Air Gap manifold drops (depending on ambient conditions) about 20 degrees more at 2,500 rpm and about 15 more at 5,500 rpm. The net worth of this in output is about 6 lbs.-ft. at 2,500 rpm ...

For years LT1 enthusiasts have been running well into the nines with factory LT1 and LT4 intake manifolds ... was definitely flowing more air as Bob added another 6 percent fuel.