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Swedish Auto motor & sport latest test: M5 E60 RWHP 471,5! :M5rev:
 

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cidair said:
Swedish Auto motor & sport latest test: M5 E60 RWHP 471,5! :M5rev:
That is an almost unbelievable number. If it's true, then let's look at what the actual crank HP would need to be:

A very efficient manual drivetrain loses only 15% to the wheels. This would give a crank HP for the M5 of 554.7 HP.

Let's assume the M5 SMG is even better, say 13% drivetrain loss to the wheels. That would give an actual crank HP reading of 542.0 HP.

On the other hand, if the M5 crank HP is around 530-535 HP, as some people have said, then the transmission loss would need to be less than 12%. That's more efficient than any drivetrain I've ever seen.

Based on the road tests I've seen, I wouldn't be surprised if the actual crank HP was considerably above 500. A crank HP of 530 with 15% loss would give you 450 RWHP. I'd like to see some more dyno tests.
 

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Sorry Gustav!

You´re always on top of things happening in the M-world :viking: .

Have to read the threads more thoroughly!! :1:
 

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Small experience from today - Ferrari 360 stands no chance to the M5 in acceleration!
 

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Very impressive numbers! :thumbsup: kinggf :M5launch:
 

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So then the "impossible numbers" we measured during the test-drive in April were correct after all.

David
 

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Before you get too carried away -

471,5 HP on the wheels. Notice that this dyno is connected straigh onto the wheel center. not the tyre (with the wheel disconnected). 475,2 Nm

Mercedes CLS55 AMG had 452,6 HP on the wheels.
Without tires on rollers, the drivetrain loss will be greatly reduced. Most importantly you have the ratio between the V10 and the AMG 55 motor. If you multiply the ratio of these by the claimed V-10 hp of 507, you get 486.7, which is almost exactly what MB AMG claims. Thus, if M understates the crank power of the V-10, MB AMG understates the power of their 55 motor by almost exactly the same amount.

There are no surprises here that I can see.

Tom
 

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impressive numbers nonetheless
 

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Well there may be some liability issues why they choose to understate their HP numbers.


Does anyone recall the problem Mazda had when they overstated their horsepower in the RX8?
 

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And you guys thought I was crazy when I wrote that I had heard about 530 hp numbers and that the 507 hp figure was pure nostalgic romance for the vintage BMW 507.
 

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bernhtp said:
Before you get too carried away -


Without tires on rollers, the drivetrain loss will be greatly reduced. Most importantly you have the ratio between the V10 and the AMG 55 motor. If you multiply the ratio of these by the claimed V-10 hp of 507, you get 486.7, which is almost exactly what MB AMG claims. Thus, if M understates the crank power of the V-10, MB AMG understates the power of their 55 motor by almost exactly the same amount.

There are no surprises here that I can see.

Tom
That explains it - The numbers quoted are not really RWHP in this case. Now the drivetrain loss of 10% - 12% seems reasonable. I'd like to see some dyno runs on rollers.
 

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Actually i wouldnt be surprised if a "normal" M5 with some more milage would make even better/higher rwhp. The car in the test did 0-100km/h in 4.7s and 0-200km/h in 14.5 which is one of the worst numbers i have seen, usually it does 0-200km/h in under 14 seconds.
 

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m3smeden said:
Actually i wouldnt be surprised if a "normal" M5 with some more milage would make even better/higher rwhp. The car in the test did 0-100km/h in 4.7s and 0-200km/h in 14.5 which is one of the worst numbers i have seen, usually it does 0-200km/h in under 14 seconds.
The times for M5 and CLS55 are exactly the same as the germantest.
The swedish AMS didnt get these numbers by themselves, they were taken directly from the german AMS. German AMS was the first carmag that drove the M5 against CLS55 against each others.

Its a shame the swedish carmag didnt messure the acceleration by themselves :grrrr:
 

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cidair said:
Small experience from today - Ferrari 360 stands no chance to the M5 in acceleration!
I'll have to second that..... We were driving yesterday, the M5 (still in break in , ooops...) with five people onboard, and me +1 in the Ferrari 360 spider. At some point on I was driving behind the M5 and noticed my friend starting tu huff and puff with the M5 - and so we floored it. The speed was about from 70 to 160 kmh. The ferrari was stickin nicely next to the rear bumper even if the M5 got a jump start. The only problem was that when we stoped, i asked my friend if he really had all the power down, and he replied that yes, I had the pedal to the metal, BUT not the "M button" engaged.........bugger. We ment to have some more interesting races but it started to rain (and we couldnt get allowence from flight control to use the landing strip ;) ) The Hummer you see is kompressor fed and running about 500hp, so it would have been an interesting race (even if the result is propably clear allready)


What a machine !!
 

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