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Laggy unbalanced bush bearing copy, (I have one here). It would be better to chuck in another few hundred and buy a good secondhand Garrett one from the for sale section, there have been a few in there recently.

Surely they are balanced, if not it would grenade after a few minutes of running, they just use oldschool crappy bearings that is the only issue.

Sure they are often poor wheel combinations making them laggy etc but I don't really know why they wouldn't last, just might get poor quality housings making them flow less than optimally.

Edited by Rolls
Surely they are balanced, if not it would grenade after a few minutes of running, they just use oldschool crappy bearings that is the only issue.

Sure they are often poor wheel combinations making them laggy etc but I don't really know why they wouldn't last, just might get poor quality housings making them flow less than optimally.

Few reasons I found when I was dealing with those 4 years ago:

1. Materials on the turbine wheel is not 100%

2. Balancing machine used overseas is a "overseas brand" or needs calibration.

3. Not all of them are VSRed (some just put 2x poorly balanced wheels together).

4. Shaft tolerance is too high

5. Some of the Ring groves and retainer groves are not deep enough

6. Some of the bearing housing castings were not up to standard.

7. Oil rings were not treated in the right way, Garrett once are lot harder and lot harder to snap.

8. Housing profile is not all 100%, Some of them were profiled out centered and angled.

9. Very roughly built. Some of them even had piston rings crushed out side the bearing housing.

10. Builder has very little knowledge about the product. So the combination is not optimized for the best out come.

All the works seems like very roughly done and slapped together. I’ve been told by one of the manufactures that one of their experienced worker can produce 20 turbos from casting in a day. I have 2x experienced engineers whom can only produce 6 turbos a day from casting.

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