I was under the impression the MK6 was K03. Interesting, can you link me to this detail. Also you're stating the EA888 is this IHI turbo as well?
Yes. The TSI is using a Malaysian company's turbo called an IHI. That is why the power band is different from the Borg Warner K03. However, IHI still designates it as a K03 since it IS in a fact a VW Casting.
Since the EA888 came around 2008 when the economy tanked, I think VW needed to source their production in a more cheaper fasion. Switching to an Asian company with some copyrights and patents solidfied there cost savings and kept the casting from being copied and sold to different suppliers.
You seem knowledgable on the subjects can you compare the two turbos? Performance wise is one more preferred over the other or is it more of a reliability thing?
Head on over to golfmk6.com and you might learn something about the EA888. What would you like to know?
I did a K04 swap and studied the Stock IHI in depth. It features a 261 Cartridge, 456 Turbine Style and a 501 compressor outlet with machine silencer. I'm assuming these are all exclusive parts from IHI and the casting for the K03 mold is supplied by VW design. As far as comparing the two yes two completely different compressor maps.
The IHI has a lot more down low and midrange spool giving EXTRA torque midrange while supplying better numbers. (EA888s were actually making around 198-200WHP from the factory), but totally runs out of steam quicker than the Borg Warner K03.
I know very little about about GTI's, the few things I do know will get me started when I get mine in a few years. If you want to know about the Cobalt SS turbocharged feel free to ask but I feel it's safe to assume you don't care about that.
I know enough about having a friend that owns one. GTIs are just my thing. I've been in this game for a while. It doesnt hurt to work for an OEM as well.