Specifications Comparison: 2021 BMW Z4 vs 2006 BMW Z4

Curb Weight

Trim	Engine	Drive train	Curb Weight	Horsepower	Weight / Horsepower Ratio
Series M40i	3.0L I6	RWD	3,457 lbs.	382 hp	9.0 lbs/hp
Series 30i	2.0L I4	RWD	3,287 lbs.	255 hp	12.9 lbs/hp

Trim	Engine	Drive train	Curb Weight	Horsepower	Weight / Horsepower Ratio
M	3.2L I6	RWD	3,230 lbs.	330 hp	9.8 lbs/hp
3.0si	3.0L I6	RWD	3,108 lbs.	255 hp	12.2 lbs/hp
M	3.2L I6	RWD	3,197 lbs.	330 hp	9.7 lbs/hp
3.0i	3.0L I6	RWD	3,020 lbs.	215 hp	14.0 lbs/hp
3.0si	3.0L I6	RWD	3,086 lbs.	255 hp	12.1 lbs/hp