Instead of welding up an exhaust to turbo manifold is it not possible to use some kind of flexi metal pipe in to a 4>1 collector? This seems so simple in comparison to chopping out wedges of tube and welding them together and should make for smoother gas flow. Seriously, where's the catch?

A simple Google of "flexible exhaust pipe" returns the goods with diameters to suit.

Has anybody done this here?

 

Look inside.
https://fbcdn-sphotos-d-a.akamaihd.n...50336180_n.jpg

 

Do most people using this forum weld a manifold then? -Or other method of fitting the windmill, such as remote mounting?