Spacemonkey, Your car will drive fine with only the manifold. I'm not sure who told you you can get more than a stock 330 but there is definitely no proof. Everyone's about 5 to 10 whp short of a stock 330. There's still something missing in the tune that BMW has hidden away. Also, I'd lose the AFE intake. It has been shown to lose power due to it's open airbox design. It heatsoaks easily. The stock design is pretty good, but it's quiet.
Francis, remember that not all dyno's are alike. Some measure estimated crank HP, some give more generous numbers, some are conservative. It's really hard to reproduce what actually happens on the road on a dyno. They're notoriously inaccurate because of the associated conditions of a run. My car has shown 218 on one dyno and 209 on another dyno of the same brand and type! Same tune as well. Even the pressure temperature, and humidity were close. The ecu is pretty sensitive to even the smallest change in conditions. But taking all of this into account, there is a gain in power and torque, but it's really hard to know exactly how much.
'06 Arctic Metallic 325i | Sport Package | 6MT | Dinan Stage III suspension | Dinan exhaust | 330i manifold swap! Click here!
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