Legend, thanks jmac, that was awesome reading. I saved it as a word document so I don't lose it! I had a couple of questions about the wave termination box. I realise it stop pulses travelling back up the exhaust.
with it being that far down the exhaust system does it help with power or noise or both. Also how critical is its position along the exhaust system, does it have to be quite close to the collector or does it just have to be before any resonators/mufflers?

After reading this on was poking round on the american hytech exhaust website and noticed they have a patent on the wave termination canister design except they run smaller versions in each primary.