Well, the B58 is a successor but they had to put a turbo on it to get S54 output levels, but the S58 is impressive - they can get up to 560 bhp and that is pretty decent, IIRC the aftermarket low pressure turbo kit for the S54 (at 11.5 compression they had to be only moderate pressure) could kick it up to the 450 + region or upward of 600 using race gas and ethanol.....