[Fraser-Z4]

Real OEM is slightly confusing when it comes to the intake manifold for the euro 323i. I have a Z4 2.5i with the same motor as the 323i - 177bhp 2.5l n52. Our engine actually only has a two stage intake manifold as standard, it only has the DISA adjuster unit on the front of the manifold (the visible one). The location of what would be the second DISA is blanked out with no way of retrofitting.

I wanted to get to 325i power levels (or 2.5si levels in the case of the Z4) so I've installed the three stage manifold, now I just need a remap. The three stage manifold works fine without a remap and the car appears to be very slightly more powerful. If I accellerate lightly through the full rev range I can feel a slight surge in power at around 3500rpm and 4300rpm so I know that both DISA's are working. From what I gather the remap needs to primarily raise the rev limit and also the high rpm valve lift to achieve the power levels of the 325i.