The Stage 1 Suspension System has been designed to address the foundation for performance handling. The system consists of a set of performance-tuned springs and carefully matched Koni adjustable front strut assemblies and rear shocks. The manifold will make no difference whatsoever, the N52B25 already has a three-stage intake, it's just tuned for a 2.5l engine instead of a 3l engine. Fitting the bigger one might actually make performance worse. If your car is a facelift model with the N53, your plan will work. That would be a 3.0, so new manifold + remap = 330i power.