[Bob Lincoln]

First of all, you won't get any appreciable boost while revving with no load. So look at boost only with the load of driving the car. And I don't believe the computer, which does control the wastegate, will allow full boost under all conditions, on 87 octane. 87 is minimum, 91 is recommended, and it does make a difference, especially in summer. Run 91 octane and see what you get.

Finally, re-check ignition timing. It should be 12 degrees BTDC while the coolant temp sensor is unplugged. You can't set the timing without unplugging the sensor. Make sure to plug it back in when done.

 

[Bob Lincoln]

I have yet to set the timing with a timing light, I'll have to pull the airbox and everything out, which isn't exactly what I wanted to do. I have yet to run in like I normlally do, which is light since I added more coolant and adjusted the ignition timing. I'll go drive it again soon, but I might not.

Double-check the cam timing first, then set ignition timing with a light. You cannot be accurate without it. And of course, unplug the CTS before making the adjustment. You do not need to remove the airbox to set the timing on a 2.2L or 2.5L engine, whether turbo or not.

 

[Bob Lincoln]

The timing marks run from 0 to 14 degrees, in increments of 2 degrees. So when standing at the left front tire, 12 degrees BTDC is the next to last mark on the right. With the CTS unplugged at hot idle, the timing should not jump around more than about 1 degree each way. Re-check it after you tighten the distributor hold-down bolt, then plug the CTS in.