M3 e92 with engine swap from my favorite BMW engine so far, the M57 3.0 Liter diesel.
Search youtube 335d drag or dyno to see how much power these engines can make!
They are torque monsters with almost no turbo lag and a very flat HP curve.
The stock trans is a ZF 6HP which is easily tuned by XHP Flashtool to shift as fast as current day DCT's.
M57 335d diesel engine from e90 series.
Tune 1- JR Stage 2.8 with stock turbos and upgraded intercooler
374 whp/ 607 ft lbs (822 Nm)
Tune 2- JR Stage 4 with hybrid turbos, upgraded intercooler, and upgraded injection pump
430 whp/ 656 ft lbs (889 Nm)
To install, unzip both folders into your assettocorsa\content\CARS folder. They will be listed below the kunos BMW m3 e92 as separate tuned vehicles.
(The sound used was very close to what a 335d sounds like. Only difference is the idle sound. Unfortunately I don't have skills with making .bank audio files for the cars