What it does is like when you're driving a stick, u wanna push it to the highest rpm possible before shifting to the next gear. in step tronic you are in Sport Mode and it wont shift to the next gear unless u step on the gas.. hope this makes sense..

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e70 '07 black out grills
tinted 35% all around
e90 '06 beyern wheels wrapped with pirelli pzero n
dropped on h & r springs
oem smoked taillight
30% tint on front
limo tint all rear
black out grill
eyelids
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weather tech rain gutters