I'm not entirely positive on the differences between the 328 and 325, but they have the same bore, stroke, and compression ratio. Also, the part numbers for the long block are the same. The manufacturing process is different for cost savings and the tuning is different.
'06 Arctic Metallic 325i | Sport Package | 6MT | Dinan Stage III suspension | Dinan exhaust | 330i manifold swap! Click here!
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