I removed my N249 this week and did some logging. I was really pleased with how the cam cover looked with it gone and solving the jerking issue on part throttle, however from the logs it seems the DV response is actually poorer with the N249 removed, taking an extra second or so for boost to settle to requested on closing the throttle. The difference between requested and actual boost on low engine loads was also greater with the N249 removed indicating the N75 was having a hard time controlling boost via the wastegate compered to the N249 via the DV.
I decided to re-fit the N249 but to see if i could tidy up the cam cover a little by modifying the bracket. Heres the engine with the N249 removed - nice and tidy!
I cut the unused part of the N249 bracket off, which usually protrudes past the vacuum chamber towards the cambelt end of the engine.
Leaving me with a shortened bracket which I ground smooth and re-painted:
Here you can see the original bracket configuration and the modified one below
I also replaced the N249 hoses with silicone ones and refitted it to the bracket, after removing the scruffy
sticker from the vacuum chamber:
Obviously it's not as tidy as with the valve removed but I feel better knowing its a little cleaner, and that the engine can control boost better - especially considering I'm running a "Stage 2" map and standard rods, so boost spikes are the last thing I want.