Report: Dynamometer finds F10 BMW M5 horsepower is underrated

Anyone who is familiar with BMW knows that the brand has a history for underrating their cars’ power figures from the factory—aside from the fact that many of them even felt that way. I remember piloting a family member’s brand new E46 325i five-speed sedan at the time and I always recalled the car feeling much quicker than its 184hp factory rating suggested. So there should be no surprise that a new report is out surrounding a find, which may suggest that BMW could be undercutting their factory power ratings for the new F10 M5.

Enthusiast site BimmerBoost claim that the F10 BMW M5 could be “severely underrated” in terms of its power production. According to the report, BimmerBoost discovered a dynamometer sheet that rated a stock F10 M5 at 527hp SAE to the rear wheels.

Click here for more news on the BMW M5.

Refresher: The 2013 BMW M5 is powered by a 4.4L V8 engine with M TwinPower Turbo (consisting of Twin Scroll Twin Turbo Technology) making 560-hp between 6,000 and 7,000 rpm with a maximum torque of 502 lb-ft from 1,500 rpm. Mated to a 7-speed M Double Clutch Transmission Drivelogic (with steering wheel mounted paddle shifters), the 2012 BMW M5 goes from 0 to 62 mph in 4.3 seconds, 0 to 124 mph in 13 seconds with a top speed of 155 mph or 190 mph with M Driver’s Package.

To put that into perspective, BMW rates the F10 M5 at 560hp from the factory. Though due to plain ‘ol physics, there will always be a measureable amount of power loss to factor in. This power loss often occurs in the drivetrain. That said, according to the dyno sheet that claims the M5 produces 527whp (wheel horsepower), the F10 M5 has a drivetrain loss of roughly 6%. However, the golden rule for all dynamometer runs is that a total of 15% drivetrain loss should be factored in, which would mean that the F10 M5 actually produces 476whp. But according to the dynamometer, it produces 527whp.

According to BimmerBoost, the most logical answer for the discrepancy would be that BMW is significantly underrating their latest turbocharged motors. Is this an issue? Well, I’m not exactly complaining.

– By: Chris Chin

Source: BimmerBoost

Photo Cred of Dyno Sheet: BimmerBoost