The E90 & E92 systems should be different from Remus, one having longer tips. If not, I suppose you would cut the connecting pipes shorter for the E90, so that it will be sucked in more. You will have to have a shop re-weld the stock exhaust back on if you want it back on. Hence the downfall to systems where you have to cut your stock exhaust.
2008 M3 Sedan- Alpine White