alemmons

iTrader: (14)

Ported the S5 Turbo wastegate as I am going with larger intake and exhaust. Unfortunately ported a little too much and now it is not sealing. Is this a big issue? I can still build it up and fix it while it is apart.

RXSpeed16

iTrader: (41)

You are letting exhaust gas by that would normally be used to spool the turbo, so the only downside is a less responsive turbo. Can't give an estimation as to how significantly though. As long as the housing structure is not weakened, I don't see how reliability would be affected.
You can also weld washers to the flapper door to cover the larger hole. That's the route I went with my S4 wastegate.

alemmons

iTrader: (14)

Did some searching and it looks like as long as 75% of the hole is covered I am good. It will add a little lag, but it will further aid in preventing boost creep. I am trying to build up the flapper to cover the hole. If that doesn't work than I will just leave it.

freemanrx7

Might as well do it right. Pull it apart and make a new flapper. You should also cut the corners inside the hotside to help flow to the wastegate.

Aaron Cake

iTrader: (1)

You'll be fine.

An open intake and exhaust easily compensates.