What year is your model..? Mine is from 1998. These are very nice cars indeed.
I had the same problem when i bought mine about 3 years ago - still have not found
any detailed information on the web...bits here & there.
I think the individual tag makes this difficult.
What i have done is obtain the vehicle's build sheet from BMW.
My car's build sheet states the engine's power output to be 150 KW.
The standard 328i power output is around 144 KW.
The additional power was obtained by fitting better exhaust esp. branches.
This was needed to overcome the extra drag caused by the addition of front & rear spoilers.
As for the rest - I do believe that the exhaust, gearbox, differential and trimming is from the 3.0L M3
Best you can do is take the car for a dynomometer test as some power and torque is lost with age.
Do a couple of runs (say 3) to obtain an average.
I do have some dyno data of my car before and during minor mods. Where in Pretoria are you from..?
Maybe we can get together to compare cars or work on this issue. PM me if interested and post some pics..!
Good luck anyways
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