Make sure the actuator has and some pretension on it the way its bolted up to your bracket and that it doesn't flex.
If it is loose, the flap wont be fully shut, or at least it will blow open early, as there less pressure to counter the pressure inside the housing and it will come on boost slowly and not hit as hard.
If not put a washer or two under it so it pulls the rod out a touch when its bolted on.
Putting one washer under the actuator made a big difference in my car.
Good work getting it to fit, i hope it hammers!
