Topspeed:

Turbo engines always have more power than the manufacturer claims.

The McLaren 720S needs to output 720hp in non-optimal weather conditions. In good conditions it might have more 5-7% or so.

I remember some AutoBild dyno tests and for example the 488 GTB had 708ps(670ps stock), AMG GT R had 615ps(585ps stock) and 911 Turbo S exclusive had 627ps(607ps stock). Thats about 3-6% difference in power.

And maybe the 720S has less transmission power loss than a regular RWD super/sports car

All I know is it's quick!

 

All wrong. 

HP is calibrated to a certain standard, with temperature and humidity and elevation, German cars especially so as they all obey the regulations per DIN spec.

They do not account for elevation or non-optimal conditions when publishing HP ratings. 

German DIN standard I believe can have a +- 5% variant. 

And the 720S cannot have a transmission that's has less transmission lose than normal, it has the exact same transmission as the P1, 675, 650, 12C. 

The problem is actually from people testing cars. They never bothered to take the engine out to do a engine dyne test.

All they do is 'estimate' driveline loss to calculate crank HP. It will never be accurate. 

 


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