Cheers folks. Yes Calum we'll be at the main events. Update Over the last few weeks I've tried more things to get to the bottom of the boost creep issue but had no luck. The waste gate was sent for testing and given the all clear. I also tried a different waste gate on it just to completely rule it out but that's didn't help either. I've fitted a 0.6 spring now, it hits full boost at 4k RPM and then slowly creeps to 0.76 by 5k RPM. Other than that, I decided to take her to Japfest last minute. The interior was quite dusty so it was all washed with the carpets and seats out. I also replaced the carpet as the old one had a few stains. Japfest: And a couple of rolling shots en route: Japfest was done by around 5pm and we didn't want to go straight home, so we spent the night in London. Typical tourist picture: Covered 600 miles all in and even with the boost creep issue, it was a good drive. Also, I think I have also found the root of the problem, I'll see if it's sorted this weekend and report back!