Renntech has set a new benchmark for the Mercedes-Benz M278 Twin Turbo V8 used in the 550 models taking tune only output to 489.7 wheel horsepower. This is a large jump over what Renntech hit previously which was 447 rear wheel horsepower last year. This graph was revealed to us by Renntech in the M278 versus N63 comparison article. No other tuner is even remotely close to where Renntech now is with the M278. This gain is thanks to the raising of certain limitations in the ECU that it seems other tuners have not been able to do.

The M278 according to Renntech seems to be capable of over 500 wheel horsepower on the stock turbos. That means with race gas and bolt on's including exhaust modifications it should be possible to push the M278 past the 500 wheel mark. Renntech also believes modifying the turbos or going to larger turbos will propel the motor to well over 550 wheel horsepower. Somebody just has to be willing to push their car and motor this far.

Great work by Renntech and congratulations to them. The M278 truly seems to be a mini-M157 motor.

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