Z4 2.5i N52B25 - 177 bhp performance upgrade.

[GadgetMart]

I know this has been done to death, but from what I can tell the only difference between the I and SI is the inlet manifold (2 disa flaps) and the SI software.
So if I was to change the hardware to the SI spec, where could I get the ECU flashed to SI specification? - The modifications won't work without it.

The other option is to sell the car and buy an SI, but it's hard to find a clean one at a reasonable price. (plus it's better the devil you know).

Any help would be appreciated.

[lucasxdiniz]

I know this has been done to death, but from what I can tell the only difference between the I and SI is the inlet manifold (2 disa flaps) and the SI software.
So if I was to change the hardware to the SI spec, where could I get the ECU flashed to SI specification? - The modifications won't work without it.

The other option is to sell the car and buy an SI, but it's hard to find a clean one at a reasonable price. (plus it's better the devil you know).

Any help would be appreciated.

3-stage intake swap is a common mod in the American market for the E6x and E9x BMWs - virtually the same engine so lot's of info in those forums. Have a Google.