I haven't tuned my X1 yet but when I added the JB4 to my 335i I didn't notice any performance gains. I'm glad to hear that you noticed a difference.
__________________
2011 E92 335i | 11.7@125 SOLD
2017 Camaro SS | 12.7@114 SOLD
2019 Audi TT RS | 10.5@130 SOLD
2020 F97 X3M | 11.0@123
2023 G80 M3 xDrive
|