New PT6466BB turbo, does the exhaust WG hole need porting?

I finally got it back together, with the 13# actuator with a very light pre-load it controls boost steady at a minimum 20psi which I have never had it lower than that in 15 years or more. Will probably add just a little more pre-load so it spools a tad better and call it done, boost Cmd is set at min, can turn it up and it does fine and steady up to 24#.
WG hole is ported out to 1.15" and alot of material was removed on the inside front radius. The back, closest to the turbine was left square to act as a wall to slow down the air flow and direct it more to the WG hole.
 
I finally got it back together, with the 13# actuator with a very light pre-load it controls boost steady at a minimum 20psi which I have never had it lower than that in 15 years or more. Will probably add just a little more pre-load so it spools a tad better and call it done, boost Cmd is set at min, can turn it up and it does fine and steady up to 24#.
WG hole is ported out to 1.15" and alot of material was removed on the inside front radius. The back, closest to the turbine was left square to act as a wall to slow down the air flow and direct it more to the WG hole.
If you can't go lower then 20psi I would say you still have issues . You are most likely runing a ton of back pressure . I would look into ether a external wastegate setup in the stock location or something plumed off the header crossover . I have a 281 cid with a 7168 comp turbo with a .85 exsaust housing and even though my back pressure is pretty high I can still get my boost down below 10psi . If you are happy with a 20psi minimum then rock it but in my opinion I would look into getting it lower .
 
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