Gave the car a bit of a spring service as it has been sitting all winter, plus I was getting a slight misfire above 6500rpm, so I swapped out the MAF sensor and coilpacks, and fitted a new set of plugs, now the misfire is gone. Oil and filter change next week and new brake pads and fluid going in too. After that I am giving the car a full detail and machine polish.
Happy to report all 4 spark plugs look normal, so the previous oil leak I had on No.4 cylinder is gone since the rebuild. No oil or water is being used either, it's all good so I am happy I rebuilt the engine correctly.
I also changed my air filter from a K&N to the Jetex FR-08001 cone filter, after reading a test which showed the Jetex was the best flowing cotton gauze air filter. Blue matches my car too!
Car is now 100% issue-free, feels very strong on boost and pulls hard to the redline smoothly and cleanly, feels great at 25psi.