All Pro Cylinder Heads - Mechanical Cam, Titanium Intake, Inconel Exhaust Little M2 Iron or aluminum blocks with

Iron or aluminum blocks with 1/2" diameter holes using 6 bolt heads (23 bolt holes per side)

It comes in three main types: Little M2

The lock up virtually eliminates heat build-up in the converter at cruising speeds while providing even more efficiency since its not slipping

At least not for long

but one or the other may be required for fitment

All Pro Cylinder Heads - Mechanical Cam, Titanium Intake, Inconel Exhaust Little M2 Iron or aluminum blocks withThis is the cylinder head we use for all of our big boost engines other than the All Pro solid heads used with billet blocks and no water. They have great airflow (see airflow chart in photoset) and are amazingly strong and here's why: 100% virgin Alcoa aerospace grade aluminum ingot with no remelt Heads have been HIP treated (hot isostatic pressing) for greater strength and dimensional stability (see video below for more details on HIP treatment) Up