Just in case you guys are wondering, below is the BorgWarner's K03S turbo's specs which is under the hood of the little Pocong. Unfortunately I couldn't get the K04's to do direct comparison but K03S already using K04's compressor size (a bit smaller than K04 meant for 2.0 Fsi though) and quite frankly upgrading to K04 might not see much gain. I've personally seen dyno chart of 1.8T with K03S outpaces 1.8T with K04 by registering 259whp/436nm but of course but of course the turbo won't last long :)
5303-988-0052 (aka KKK K03S) Compressor part no. 5304 123 2029 Compressor size code/Geometry K04-2075E Inducer: 38.1 (75% of exducer) Exducer: 51 Tip height: 4.4 Blades: 4 long/4 short Turbine part no. 5303-120-5037 Exducer: 40.34 Inducer: 45 Tip height: 6.8 Blades: 11 long
Self confessed rempitster which isn't really fast, just pretending to be fast. Norm for him to have a very shallow pocket at the end of the day after doing some mods perceived to be slow, 'cheap' but definitely special on the Pocong GTI