This BMW 335i uses the earlier N54 twin turbo 3.0 petrol engine and came to us for some rolling road testing to see what power the car was producing. The only performance modifications made to this car were the intakes and a JB4, as well as a long list of cosmetic modifications.
The graph below shows the power and torque produced with the various maps available on the JB4. Map 0 is stock, map 1 is a map designed to be used with 95 ron fuel or if you're only looking for a small increase. Map 2 is a stronger map focusing on high rpm power. Map 5 is designed to give a lot of torque early down but not as much in the high rpm.
Best power gain: 37 bhp
Best torque gain: 88 nm