External wastegate
 

In the process of finding out why my buddies turbo mustang wont outrun me we discovered the Garret/Tial wastegate seat was gone. Do they burn away or was it just omitted before he got the car? You could see where there was one there once but none now. Just currious.Thanks Rod 35mm if it matters.

Must have been left out, that thing must have spooled really slow with that big of a exhaust leak.

Dad probably took the Waste-gate seat out to keep Junior from making any real power when he wanted to drive the car.

Tom Vaught

Remember, you use a large wastegate to take away exhaust energy that would be going to the turbine, You want to make a lot of power you can run a smaller waste-gate(s) because you want more energy driving the turbo(s) making boost, not escaping out the exhaust pipe.

Tom Vaught

In the cool it would build 12psi but in the heat could only muster 10psi. Amounted to a 1/8 inch circuler leak of 1 3/4. Tom we are both to old to have dads. Just never had a reason to take it apart there. So it looks like I may be in trouble next time out. Rod

Many wastegates come with different sized seats so it can be used on multiple sized tubing. If someone built the system that was new to wastegate products or just plain forgot, they may have not known to add the right seat or, again, forgot to put it in. I could see where someone may have forgotten to put it in. You said it was a 35MM gate, but the pipe used may have been a 38mm or a 44mm and they used a 35mm intending to add the seat adaptor?? Just a guess. Mark L