HP 425 or 431?

[accce]

What is the actual HP? the reviews have it at both 425 and 431. Ae the US speck cars different than the European cars?

[jc05e46m3]

[CanAutM3]

425hp SAE = 431ps DIN

[BlackCobra08]

As usual in America we have different units we measure HP in, although in this case it's very very similar. The 431 figure is the metric HP measurement, which you may sometimes see the letters PS aside it. It's German for Pferdestarke or 'continental horsepower'. 1 PS HP is equal to 0.986 Imperial HP. So if you multiple 431 * 0.986 you get 425

[accce]

Thanks for the clarification!

[M6-Coupe]

There is another trick here!
As members explained and they are correct 431 PS (Mettric horsepower) = 425 HP(Standard horsepower), but in this case it is something else.
BMW matches his car for US with Actual horse power. what I am saying is M4 has 431 PS for European customer while it has 431 HP for North America. in fact they tune the car a little for North America. They did the same thing for M5/M6. the European version has 560 PS (552 HP), while the US version has 560 HP.
a little more horse power for slightly heavier car.
look at the link below for 2013 M6 Coupe.

http://www.automobile-catalog.com/ma...3_m6/2013.html

[CanAutM3]

Originally Posted by M6-Coupe

There is another trick here!
As members explained and they are correct 431 PS (Mettric horsepower) = 425 HP(Standard horsepower), but in this case it is something else.
BMW matches his car for US with Actual horse power. what I am saying is M4 has 431 PS for European customer while it has 431 HP for North America. in fact they tune the car a little for North America. They did the same thing for M5/M6. the European version has 560 PS (552 HP), while the US version has 560 HP.
a little more horse power for slightly heavier car.
look at the link below for 2013 M6 Coupe.

http://www.automobile-catalog.com/ma...3_m6/2013.html

Not the case for the F8X M3/4. They are clearly advertised at 431ps in Europe and 425hp in NA.

As for the M5/6, I seriously doubt the NA cars are tuned to produce more power. It is more likely a marketing fluke and/or a regulatory loop hole.

[M8 JTD]

All BMW UK literature quotes 431hp not 431ps for a UK spec M4.

[M8 JTD]

Even the official BMW Press Pack quotes 431hp!

Here is my theory/explanation:

The key to the 425hp (US) vs. 431hp (UK) discrepancy is within page 25 in the attached press pack – Note: "Fuel grade: RON95 – RON98"

Therefore the official BMW.com (inc UK and Europe) figures quote 431hp as this is what the car will produce using the fuel compression map for a minimum octane grade of 95 RON – 98 RON (“Regular” = 95 with “Super” ranging from 97-99 here in the UK).
BMW USA quotes 425hp and fuel grade RON91 as this is what the car will produce using the fuel compression map for a minimum octane grade of 91 RON. I assume they have done this due to the fact that on average fuel octane is typically lower in the US than UK (“Regular”= 85 AKI (90 RON) & “Super/Premium” = 91 AKI (95 RON).

+ If you are US based and able to source higher octane fuel, the car will only produce the higher hp figure if BMW equip US spec cars with the higher fuel compression maps – As with older cars in the UK, there is no point in using “Super” if the car doesn’t have the appropriate fuel map to utilise it.

[bimmerj]

I think specs in the UK interchange the 735.5 and 746 W quite often.

[CanAutM3]

Originally Posted by M4 JTD

Even the official BMW Press Pack quotes 431hp!

Here is my theory/explanation:

The key to the 425hp (US) vs. 431hp (UK) discrepancy is within page 25 in the attached press pack – Note: "Fuel grade: RON95 – RON98"

Therefore the official BMW.com (inc UK and Europe) figures quote 431hp as this is what the car will produce using the fuel compression map for a minimum octane grade of 95 RON – 98 RON (“Regular” = 95 with “Super” ranging from 97-99 here in the UK).
BMW USA quotes 425hp and fuel grade RON91 as this is what the car will produce using the fuel compression map for a minimum octane grade of 91 RON. I assume they have done this due to the fact that on average fuel octane is typically lower in the US than UK (“Regular”= 85 AKI (90 RON) & “Super/Premium” = 91 AKI (95 RON).

+ If you are US based and able to source higher octane fuel, the car will only produce the higher hp figure if BMW equip US spec cars with the higher fuel compression maps – As with older cars in the UK, there is no point in using “Super” if the car doesn’t have the appropriate fuel map to utilise it.

IMO, this theory is incorrect.

It is simply a question of unit used. This SAE and DIN difference has been around for years. It is not something new. Inernet made this more obvious because now it has become easy to see the specs from different countries.