I have a 99 c230 k manual and I went to a rolling road day yesterday in Liverpool and it was one of those hub dynos. Anyway my car only did one run as its running so lean the guy seems to think it could be the fuel pump as the car has done 152 k. Or maybe it's the big air filters I have,either way it's not good has anybody had this problem it's down about 40 bhp but still pulls like a train but now I'm advised not to take it over 4000rpm. He told me though with a t30 turbo and standard internals I could get 400bhp cos he's done one but mapped it to 350 piece of piss. Any help would be great thanks