Is there a write up on this? If so can you post a link? I have never heard of anyone doing this, didn't even know it was possible?
Here's a right up I started awhile back on LLY turbo's I've done, there's a few video's as well.
http://www.duramaxdiesels.com/forum/showthread.php?t=52437&page=9
Page 1, post #4 has videos I took of an LLY with a batmowheel, stock turbine wheel, fingers vanes, and ported/polished. Page 7, post 97 has a short video of an LLY with a TCT comp wheel, 10 blade turbine wheel, fingers vanes, and ported/polished. Page 8, post 108 has a ride along video of that same turbo as page 7.
There's not really a right up on replacing a turbine wheel per say. You basically take the turbo apart and replace the turbine wheel.
I've done a few turbos now with the 10 blade turbine wheel, it sounds good. They should flow more air in general being it has less rotating mass and larger pockets to fill with air.
I also haven't heard of anybody say it's laggy down low, the opposite in fact.
Porting/polishing will open it up and smooth it out so it can flow more air. It will also lower your boost pressure b/c you're reducing restriction, there for it doesn't have to work as hard.
As for sound, you can get that from a compressor wheel, turbine wheel, and opening up the exhaust housing. For the VVT turbo's I can only open them up to a max of 3" due to the size of the downpipe. Just that little bit though increase the sound quite a bit.
Now for the IHI's I open them up ALOT!!! That makes them sound like a jet!!
:thumb:
Sorry for the long post OP, there were lots of questions and I wan't to give answers based on my experiences.
If you have any questions or need parts let me know.
Yellowchevy