Quote Originally Posted by wheming View Post
I wonder though if it could be opened up enough. I think the fact that this is a ball bearing turbo, it really requires a larger wastegate, since it takes less to spin it up to pressure.

I pumped the actuator up to 25-30 psi, so it was open as far as the srm would travel i imagine. But, i could disconnect it. It is a bit of a tight squeeze with this .63 turbine housing and the 2pc lower manifold. That is why i opted to pump the actuator. I could try again though, it would be less work than removing turbo.
Assuming your turbo/WG setup is like mine, and you want to disconnect the arm, first you got to get a little screwdriver in there and pop the E-clip off without dropping it.

Then you have to pop the arm off, which should have some preload, so it will fight you a little bit but not too much. Or you can pump it out to take away the preload. Then I'd remove the actuator entirely to make sure the rod laying there doesn't interfere with the flappers ability to flap open.

Once you want to put it back on though, you are going to need to pump it out a bit to create that preload again. Then get the e-clip on there hopefully with just finger pressure because getting pliers in there is tricky and/or more likely to send the E-clip flying.

The ball bearings should have a negligible effect on steady-state efficiency. The bigger impact will be how efficient your turbo (turbine + compressor wheels/housings) and engine are overall, as far as how much less exhaust gas flow you need to reach your operating point.

I think it might be possible to measure if the WG puck is being forced open, by connecting the actuator to a vacuum gauge and seeing if the needle moves and how much. Could test that on the bench. The actuator itself has no bleed holes right? So pulling on the rod should generate a vacuum in the diaphragm chamber.