The internet is full of experts who swear they know they answer to this question, but very often the information you get is based on seat of the pants feelings, or straight theory, and while that’s great there is no replacement for actual dyno testing. In this one from Richard Holdener you will get all the details from the dyno where he’s putting LS3 and LS7 heads to the test in a few different configurations. So if you are debating which ones to put on your combo, you are going to want to watch this.

Video Description:

STACK INJECTION LS TEST! WHAT HAPPENS WHEN YOU REMOVE THE PLENUM ON AN INTAKE? LS3 VS LS7-WHICH HEADS MAKE THE MOST POWER? 427 LS7 HEAD TEST-CNC-PORT LS3 VS CNC-PORTED LS7-WHO WINS? CAN PORTED TFS LS3 HEADS SUPPORT A 427 STROKER? SHOULD I UPGRADE TO LS7 HEADS ON A HIGH-HP 427 STROKER LS? WHAT IS TYH EBEST HEAD CHOICE FOR A HIGH-RPM 427 LS? WHAT HAPPENS WHEN YOU REMOVE THE PLENUM ON AN INTAKE MANIFOLD? HOW WELL DOES AN INDIVIDUAL-RUNNER MANIFOLD (STACK INJECTION) WORK ON AN LS? CHECK OUT THIS VIDEO WHERE WE COMPARED TFS 255 LS5 HEADS TO BES-PORTED LS7 HEAD ON A BTR-CAMMED 427! WE ALSO FOUND OUT WHAT HAPPENS TO POWER WHEN YOU REMOVE THE PLENUM AND THROTTLE BODY COMPLETELY!