Originally Posted by Chip-3Door
Originally Posted by JjCoDeX75
So what we need is variable ports! Ones that are nice and small when you are off boost, but expand nicely when on boost!
Hmmmmm - maybe not!
So given that my truly innovative cylinder head above is unlikely to be the correct solution, is it possible to compensate for the reduced flow any other way?
JJ
You want variable port sizes, variable compression ratio, and mapped valve timing under solenoid control, so that you can alter the timing and duration of opening and even the acceleration rate to be optimum, this is the direction things are heading.
By altering the cam timing alone you can see quote good gains in terms of recovering lost bottom end, in fact this is what your M5 does to tame its relatively racey cams
To be fair, the M5 cheats - what with its VANOS system. But this at least shows how the M5 can have its cake so as to speak and eat it!
Cool - we have established that it is more important to improve the shape of the port over the overall size.
Lets go back to the compression ratio. Can we further discuss exactly how the compression ratio affects the whole engine efficiency, and what makes them initially not so good without proper setup
JJ
JJ