With my 05 s40 t5 is it worth upgrading the turbo and if so can someone recomend a site and type of turbo I could/should upgrade to.

 

It's kind of hard to upgrade the K04 on the S40's because of the integrated exhaust manifold design. However ATP has turbo kit for the cars using a new manifold and turbo, I don't remember if it comes with a new downpipe or not though. Also there is some success in using the K16 turbofold off the Euro Focus RS.
I think that's the best way to go, but it's also a lot of money not including the tuning that it will require.

More info here...
Swedespeed Forums - K16 has arrived

 

Cool thanks for the info

 

Could just go with a tune if you aren't looking for too much of a gain, since the new turbo would need a tune anyway?