Hmmm... 3.0 DI? Sounds like an N53, but the US didn't get these. The N52 is the ULEV and the N51 is SULEV (or is it PZEV?) You can tell by the presence of a 3-stage intake manifold. You'll see a box with a cable attached to it right next to the "BMW" on the manifold itself. Thats one of the DISA valves. If you have it, it's an N51. If it's the single stage manifold (ie no valve), its an N52.
'06 Arctic Metallic 325i | Sport Package | 6MT | Dinan Stage III suspension | Dinan exhaust | 330i manifold swap! Click here!
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