Emissions standards are really the only difference between the B46 and B48. For the consumer there are no important changes between the two engines. The B46 is a Super Ultra Low Emissions spec (SULEV) engine, and is the primary engine available in the US.
BMW only used this engine on 2020+ 540i, 740i, 840i, X5, X6, and X7 "40i" models as well as the 2019-2020 Toyota Supra.
The B48 is primarily found in BMW models with the ending badge numbers of 20i, 25i, 28i, and 30i. A higher output version of the B48 is in some 2019+ 35i models. It's also in some Mini models along with the Toyota Supra.
Rear lip carbon fiber performance spoiler BMW 3 series sedan 2019+
Code: 121 14 G2 120
Your Price:$279.50
Rear lip carbon fiber Supreme performance spoiler BMW 3 series sedan 2019+
Code: 121 14 G2 150
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Downpipe for BMW 230i/ix320i/330c/420i/430i/ix/X3/X4 B46 2019+
Code: 130 10 46 100
Your Price:$495.00
Your Price:$269.50
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