| the problem is with the PE's wastegates but I have observed peculiar behavior with them hanging or binding which leaves them cocked open slightly. Two vehicles I have tuned with them have shown the same problem. It appears to be thermally dependent too as I would make a couple dyno pulls and turn the engine off and a few moments later I heard a distinguishable 'clack' from the wastegate finally snapping shut. I climbed under the car immediately after a pull and watched the wastegate on the driver's side to confirm this. This is the only problem I have seen in 2 PE cars and it has been on the driver's side only. When this occurs, the driver's side turbo will spool up with significantly more lag which also affects the A/F reading of dual-pop vehicles on the driver's side bank by leaning since the passenger turbo is flowing more air and it feeds the driver's side of the engine. In the event that the car is driven hard continuously, the wastegate wont fully shut on the driver's side which could lead to engine damage from running lean and the car will feel a bit laggier during this time. I did have a hand in the PE turbos that were installed into these two vehicles. Checking for wastegate issues and checking balance between the sides is something I do at Z1 when overseeing an engine build project. I specifically recall these turbos and the slightly thinner brackets used for mounting the actuators. It did not appear to me that the bracket would be of any consequence to the behavior of the boost control - my primary concerns were with the connection between the actuator rod and the wastegate control arm as the arm simply has a hole in it rather than a pin-stud like a stock turbo arm has. The PE setup appears to just call for a bolt to connect the rod to the arm, but this causes binding when the wastegate is opened since the eyelet collar at the end of the actuator rod only has a short flat plate and the larger diameter of the collar would hang up with the edge of the wastegate arm. We ended up modifying the wastegate control arm by welding an off the shelf pinstud which raised the collar plate enough to allow the rest of the collar body to clear the arm when the gate was opened. Even despite this work, there was still a binding issue on the driver's wastegate. I am suspecting that it may be interfering with the downpipe, but that's only a speculation right now. It seems more likely to be a design issue in the wastegate mechanism (carbon-clogging?) or in the actuator itself. Personally, if I were dead-set on PE's I would get my hands on some stock actuators - they should bolt up with very little fabrication (since the compressor housings are similar in size to stock turbos), but I would be sure that there is ample spring pre-loading on the actuator - a good 3/8" of spring preload from rest position. You could even cut off the end of the actuator rod and use a die to thread the stock actuator rod for fitment of the PE's adjustable collar. Otherwise you will be left to trim the rod length and re-weld it back together. Stock actuators will likely provide the tension you need for higher boost and it will eliminate a possible problem.. We have been able to achieve ~28psi with our stage2 turbos and stock actuators. Those turbos use a stock turbine housing (.63 A/R) so there is considerable backpressure working on the wastegate. My jury is still out on the subject though - I dont have enough info to make a good determination.
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