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      01-24-2013, 05:41 PM   #326
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Drives: F30 328i M-Sport
Join Date: Mar 2006
Location: Hong Kong

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Originally Posted by bradleyland View Post
You should really step back and listen to what you're saying. Essentially, it's one way for one engine, and an entirely other way for another. They're able to build U0 engines entirely to spec, but the O0 engines are binned according to their output. Does that make any sense at all?
Firstly u must distinguish between the high compression & low compression U0 engine. The high compression U0 engine cannot run at 28i's level of boost cos of detonation (even tho the turbo is identical) whereas the low compression ratio U0 can (as it's identical to O0). This is confirmed in the article by BMW China's technical rep (they build both U0 & O0 at Shenyang China). So the U0 is already less stressed than the O0. In any case the high compression one doesn't need binning at all cos all defective ones are junk as there's no lower state of tune than U0 for a N20. The low compression ones are tuned to U0 or O0 from binning. U0 & O0 is only the engine code for it's state of tune, other than that it doesn't identify anything else. So, U0=20i & O0=28i.

Originally Posted by bradleyland View Post
So you (or someone) has verified every single part number and every aspect of the software running on these two engines? There is a gulf of difference between "they are identical" and "we have not identified a difference".
We (a number of us) identified key parts for the low compression version & they have the same part number. The software is of course not the same (but the DME part number is identical). The "identical part" came, again, from the BMW China tech rep from the article. He explicitly said, when questioned, that the high compression U0 & low compression O0 is identical in every part except for the pistons.