View Single Post
      10-16-2014, 02:05 PM   #4
MilehighM3
Brigadier General
MilehighM3's Avatar
United_States
961
Rep
3,474
Posts

Drives: Harrop E90 M3
Join Date: May 2011
Location: Colorado Springs

iTrader: (15)

Garage List
2009 E90 M3  [6.50]
Pretty much every supercharger kit at altitude will suffer a boost pressure loss due to the lower atmospheric pressure. If you want to run the 6-6.5psi that the kit is designed to run, you will likely need a pulley 7-8mm lower than what's provided. I'm not sure what your altitude is, but we are at 6,000' and 8mm is about right, maybe just a tad less than desired. Boost pressure will also be dependent of the exhaust back pressure, so keep that in mind as well. A catless car will make a little less boost, but more power as a result of better flow.
Appreciate 0