JB Stage 1 N55 X5
 

Hey there. Had the JB on for about 10 days and the extra power (up to 50hp claims) is just not there. Feels a bit sluggish on bottom end. Boosting about 10 lbs. Had many turbos before and you should definitely feel 50 whp difference. Ran a few times with a friend with a '13 335i and pulled away every time. Any experiences out there?

I would be surprised as well to not feel a difference, but even at 50whp a 335 is going to walk you hard, that's a HUGE weight difference to account for. I believe it's nearly 1400 lbs. An old metric that I was once told was 10lbs/hp for a simple comparison. So to really keep up with a 335 you need 140hp (ballpark) to account for the weight.