Wastegate exhaust side
 

I was just wondering if it matters which side the exhaust blows into? I would like to mount the wastegate so the plunger faces out, but I'm afraid that exhaust pressure will make it harder for the wastegate to open.

yes it matters. the exhaust needs to flow into the bottom of the wastegate pushing against the plunger. once the plunger opens the exhaust will flow through the wastegate and exit out the side port. exhaust flows at ~700 ft/sec so if you reverse it then you are putting a force on the back of the plunger that the diaphram may not be able to overcome. also you are exposing the inside of the wastegate to exhaust all the time which will overheat the wastegate and burn up the diaphram.

Thanks, thats what I was afraid of. Guess I should have asked this before I had them weld on the flange. The wastgate just going to sit funny off the manifold, oh well now I know for next time.

have them cut it off and reweld it.