Originally Posted by
Drifter
I had similar issues using the standard inlet manifold with bigger injectors. Instead of the larger turbo making more power it did less (went from TD06 at 440bhp to GTX3071 at 400bhp). I ended up with the Greddy Shortport plenum, same injectors pump etc. Also added adjustable pulleys and it gained 100bhp :) That was using a Fuel Performance pump with better flow than a walbro though. I've since ran in a new fuel supply line and fitted a Bosch 044 in a tank which has dropped the injector duty down out of the high 90's.
That wastegate outlet on the manifold does look a bit shit if I'm honest. I'm still using my copy of the TD06 manifold, with the smallest Tial wastegate, 38mm I think, never have any creep issues. Hopefully you can just chisel off the coating around where you need to change the manifold?