Is there a way I can test my new 38mm Tial before installing it?

 

One thing I did was to apply pressure to the side port to see that the WG valve opened. I used a simple bicycle pump and teed in a pressure gauge to measure the pressure at which the valve opened. The pressure that opens the valve should closely match the spring rating in the Tial.

 

I don't have a gauge but will test the basic function with a hand pump. Does the valve open in or out?

 

The valve pulls into the housing. Reworded: the valve pulls away from the exhaust pipe.

I've never seen a TiAL come off the assembly line dead (heck, I haven't EVER seen a dead TiAL wastegate) but you're more than welcome to check.

 

Ah ha! In the lower left image, the valve moves upward to control boost:

http://www.tialsport.com/images/38mm_drawing.pdf