shorty link pipe fitted

[tomlinscote]

Can I ask a qn? How does exhaust pipe length make  a difference to power or torque I have heard about back pressure but never quite got the hang of it, if you didn't even have an exhaust manifold just let the gas out from the cylinder head surely that would be easier for the engine, and yep I get that you need to  control where the gas goes and sounds like but ideally........??

P