So your saying the cfm and velocity isn't related ? If we improve the turbulence inside the head it wouldn't flow more? Or simply saying the velocity characteristics isn't what limits our cfm.
What's the stock velocity of these heads? Aeb vs awp? fps.
What exactly controls the air speed though. From the top of my head you would have different variables for every motor right? Like you need your head to flow the necessary flow to support a the engines displacement (which changes with strokers) and rpm band. If your ports are to large to flow a good inertia wouldn't we see a drop in voliumetric efficiency? So for larger motors and high rpm motors larger ports be ideal but small ports are better for power below 5000pm and smaller motors.
So if someone were to port and polish their head adding some sort of velocity stacks and and knife edging exhaust on the exhaust side. Make for less resistance for the flowing air, and in turn it moving faster through the head
So you're question is... will machining work and upgraded components yield increased power output? Or is this all rhetorical? I think you need to do some reading before asking fundamental questions regarding cylinder head flow, or this thread will get out of hand.
CFM and velocity are obviously related. Q = V x A
You can port the head to increase area, improve manifold characteristics and runner size to increase velocity and area. If your area is too big for the displacement of the motor you decrease velocity. Etc. Etc.
The variables are all the same no matter what make or model
Yeah, I obviously have a lot more reading and learning to do.
The questions I was asking were all theory based,
I'm just have trouble finding good resources to start learning from, I have some general concepts but need a good foundation to build on. Not asking to be spoon fed information, but does anyone know a good place to start learning and reading it seems ill read hours into stuff but then get hung up on basics again. .
is this 2004?
Seriously the 4.2 heads are a complete PITA to make work.
Even if you wanted to take full advantage of the rocker arm set up , you will still need custom cams (don't try and run the V8 stock cams unless you want to bend all your valvetrain using it on a 4 cylinder) as well as custom valvetrain as the S8 internals are slightly different to off the shelf 06A 1.8T components.