Afternoon all... I am new to the forum and this being my very first post I have recently had my car remapped with Unicorn Developments in Stockport, friendly staff and what appeared to be a good service and positive reviews. However at the end of the power runs and mapping process I was told that the cars diverter valve would need replacing as I wasn't gaining the full amount of boost I needed to get to. The results on paper looked good though, my car is a 57 plate 2.0 tfsi TT and the only modification is a Miltek Quad exhaust set up (not all the way through to the down pipe though) which was added by the previous owner. On my initial power runs I was told the car is running above the stock power of 200bhp and was at 223bhp due to the exhaust. After the Map was added it came out at 248 bhp and torque from 230nm to 290nm ...but it was marked up on my print out as - boost leak diverter valve. The owner Rick said he would help me get the diverter valve changed for a reasonable fee, and also mentioned to add 99 ron fuel as on the day of the map I had unfortunately had to use 95ron Tesco fuel as they was out of stock on the 99ron....I was told that my fuel timing was off because of this and to just go back to the 99 gear and it would sort itself out? fast forward a couple of weeks now and I had called a few times and spoke to lady on reception at Unicorn to get my car back in for the DV to be fitted to fix the small issue.. after 4 separate calls and promises of calls back I heard nothing So I decided to have the DV replaced elsewhere, I took it to a VAG specialist in Manchester and I got a call back on the day of fitting to say my DV was in perfect working order? not tears or damage to the spring or diaphragm and they said it looks like new, I asked them to go ahead and change it anyway for peace of mind with exactly the same revision model they had just taken out. So I am still left with a problem on the car not getting to optimum boost requirements for the map I think and down a few quid on a job that didn't need doing sadly. On driving the car it doesn't feel that noticeably different from before really. Does anyone know where I go from here to solve this issue, I spoke to a place called Awesome GTI who were very helpful but they talked me through what they do on there map process and checks involved prior to adding a map and logging that is done to identify any small problems so they can be fixed on the day prior to a map being and to ensure the problem is correctly diagnosed which sounds good but to late now I have already had it done and left scratching my head on what's required putting right. I am hoping someone with more knowledge than me on boost issues could help? I was going to call Unicorn back but after several attempts and speaking to them they have yet to call me back so kind of given up on that one many thanks in advance for any advice and input.