K, well from an engineering point of view and explained simply and quickly, there are two major components of your exhaust, the exhaust flow, and the pressure "WAVE".
You want to size headers and exhaust big enough that you have as little restriction as possible, but you still want to keep a minimum exhaust flow rate.
2nd part, and what most people forget, (including performance shops here in winnipeg which I have sadly come to realise) is a pressure wave that begins right after the exhaust valve opens, when this pressure wave reaches either your collector, or the atmosphere it changes form, part of it will leave the pipe as a positive pressure, part of it will come back as a negative pressure.
Now "tuning" your exhaust properly which is impecably done on the F1 formula cars, this pressure wave will return to the exhaust valve just before it closes, sucking or "scavenging" the last little bit of exhaust out of the cylinder AND providing a negative pressure in the chamber to suck new charge into the cylinder.
Now for this test run, until I can find some way dyno testing my theories, I will be tuning to around 5000rpm, because this is approximately half way between peak torque and peak HP.
I will try and keep people updated as things progress, but I'm not much of a forum junkie, so please don't expect prompt replies or updates
