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Discussion Starter #1
Hi people just became a new member of M5board and got to say some real hardcore enthusiasts here. I am from the UK and purchased my 2005 M5 about 3 weeks ago, i have a few questions to ask the more knowledgable members, but the first is, i went to get it re-mapped and a rolling road session and asked the guy to check it was stock before he did any mapping, the rollers recorded a figure of 561.5bhp, the guy who has been in the business since the late 60's was absolutly gob smacked and couldnt figure out how this came about, especially as i purchased it from a BMW dealership. Even with a previous re-map it should in theory produce about 530-535bhp, so after speaking to numerous tuning companies in the UK and e-mailing several european companies they all said M5 and M6 always give over the 507bhp claimed figure some as much as 525bhp in standard form.



 

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Welcome aboard. I suspect the car has been chipped. Impressive nonetheless - congratulations :thumbsup:

P.S. Please check that all the recall work e.g. vanos oil pipe replacement has been carried out since it's such an early car.
 

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Welcome...That dyno is rubbish. You only want to post RWP numbers, not these fabriacted flywheel numbers.

But welcome.
 

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The figures are not fabricated per say, it is just that in order to have numbers that are equal on all levels, we need RWP as opposed to flywheel power that can easily be manipulated.

RWP can also be changed, but if the runs are made in 4th gear like most everyone else, than the numbers will be even.

No one uses HP numbers when posting Dyno specs. It is just what is common and what is not. Your dyno posting is not in the normal calculations.

Like what was used for driveline loss?? 15% 20% 25%??

If you post RWP than there is no need to factor loss in. And the dyno will be apples to apples.
 

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Discussion Starter #8
The figures are not fabricated per say, it is just that in order to have numbers that are equal on all levels, we need RWP as opposed to flywheel power that can easily be manipulated.

RWP can also be changed, but if the runs are made in 4th gear like most everyone else, than the numbers will be even.

No one uses HP numbers when posting Dyno specs. It is just what is common and what is not. Your dyno posting is not in the normal calculations.

Like what was used for driveline loss?? 15% 20% 25%??

If you post RWP than there is no need to factor loss in. And the dyno will be apples to apples.
Cosmos, i just brought the car, i aint that technical when it comes to dyno's and tuning, all i know is the the company that did the run has been established over 40 years and the dyno is the rated in Europe as one of the best, but hey, i can only go on what is said to me, but you obviously know more then most tuners in the UK and Europe so i appologise for posting incorrect information
 

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The information is correct. Just not in the standard format that is used for comparisons to other dyno sheets.

Just ask the company to give you the Rear Wheel Power #'s.

You will not have to go redyno the car. They just recalculate and reprint the same dyno run.

:cheers:
 

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Discussion Starter #10
The information is correct. Just not in the standard format that is used for comparisons to other dyno sheets.

Just ask the company to give you the Rear Wheel Power #'s.

You will not have to go redyno the car. They just recalculate and reprint the same dyno run.

:cheers:
I will ask, cheers for the heads up
 

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I think it's GREAT, no matter what !!!!! Hey NICE color.
 

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I will ask, cheers for the heads up

To clarify what Cosmos is saying, when you dyno the car, it calculates rwhp. To get to crank hp, it figures in driveline loss. Since nobody knows the exact driveline loss, the resulting numbers can vary widely. If you get 425 rwhp and assume 15% loss, you get crank hp of 500, if you assume 18% loss, you get crank hp of 518 and if you assume 20% loss, you get crank hp of 531.

Wihtout knowing what factor they used for drivetrain loss, it is impossible to compare your car to others. That is not to say that they dyno was not done by a quality shop, just that we are missing a key factor to the equation to tell you how big your smile should be.:)
 

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Discussion Starter #13
Thanks for the nice comments, i will contact the shop ASAP and get this figure if not for just for my piece of mind. I have also just had the K&N filters fitted today and my Eisenmann Race level Exhaust should be arriving in the next 4/5 days from one of your sponsers here in the UK (CA Automotive) will post up pics when fitted. thanks again guys
 

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Fullhouse,

Hello and welcome!:applause:

To add what others are offering you, I would like to provide my experience on the Dyno Dynamics Dynamometer. You would need to concede that the correct method to read "truer motor power" would be at the wheels, not at the crank. As stated, there is a loss, as power is transfered from the crank through the drive train to the wheels. Most, if not all, measure our cars performance as rear wheel horse power.

My car completely stock was dyno'd on a Dynamometer. My rear wheel horse power was 387hp!:eek:oohhh: A Dyno Jet or Mustang Dyno would yield higher results. This is due to many variables, but primarily the concept of load bearing verses wheel spin. I personally feel the Dynamometer is the more accurate reading dyno. It does not yield the high "feel good" numbers that many want for bragging, but if you look at the dyno session set up, you would have to agree. Hood remains closed, as is in real life. Fan replicates a 70 mph speed and the power is obtained by load not the spin of a third party drum (which is the technology of Dyno Jet and I believe Mustang).

Since my initial dyno, I have performed modest and conservative mods to gain additional whp, such as crank pulley, air scoops and removal of charcoal filters and swap out of stock air filters. I was able to obtain a 17whp gain. On a dyno jet, it may have been 20%+ higher.:dunno:

For what it is worth, all that matters is how you feel in the car.:M5thumbs:

Good luck & :cheers:
 

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Thanks for the nice comments, i will contact the shop ASAP and get this figure if not for just for my piece of mind. I have also just had the K&N filters fitted today and my Eisenmann Race level Exhaust should be arriving in the next 4/5 days from one of your sponsers here in the UK (CA Automotive) will post up pics when fitted. thanks again guys
My advice, please rethink the K&N filters and look into the BMC. There are a number of threads on this issue, please perform a search. In addition, look into a BMC filter and RPI scoop package. You will be very, very happy with the result!!lovelove
cherrsagai
 

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426rwhp stock should be an accurate avg reading for an M5/M6. Not as much drivetrain loss as with AMGs so E63's dyno c.406rwhp

Fullhouse,

Hello and welcome!:applause:

To add what others are offering you, I would like to provide my experience on the Dyno Dynamics Dynamometer. You would need to concede that the correct method to read "truer motor power" would be at the wheels, not at the crank. As stated, there is a loss, as power is transfered from the crank through the drive train to the wheels. Most, if not all, measure our cars performance as rear wheel horse power.

My car completely stock was dyno'd on a Dynamometer. My rear wheel horse power was 387hp!:eek:oohhh: A Dyno Jet or Mustang Dyno would yield higher results. This is due to many variables, but primarily the concept of load bearing verses wheel spin. I personally feel the Dynamometer is the more accurate reading dyno. It does not yield the high "feel good" numbers that many want for bragging, but if you look at the dyno session set up, you would have to agree. Hood remains closed, as is in real life. Fan replicates a 70 mph speed and the power is obtained by load not the spin of a third party drum (which is the technology of Dyno Jet and I believe Mustang).

Since my initial dyno, I have performed modest and conservative mods to gain additional whp, such as crank pulley, air scoops and removal of charcoal filters and swap out of stock air filters. I was able to obtain a 17whp gain. On a dyno jet, it may have been 20%+ higher.:dunno:

For what it is worth, all that matters is how you feel in the car.:M5thumbs:

Good luck & :cheers:
 
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Discussion Starter #17
Once again thanks for the kind words and sharing your knowledge on the dyno readings, one other thing i would say is, because of the figure my car achieved, the technician actually thought the machine might be at fault, so once we decided not to fettle with the ecu and take my car straight of he put another customers M6 straight onto the rollers and the M6 pulled 512bhp and this was completley stock so although my figures might be a little optimistic then i guess that would be the same for the M6, anyways enough of the Dyno stuff, again i appreciate everyones input on this matter and hope i get the same honest feedback on any other queries i get, cheers.

As far as how i feel when i drive, lets say i get an average 8mpg and about 110-130 miles to a tank and i cant stop driving the thing, my previous car was a CL55 kompressor and although the power was there the handling and feedback was crap
 

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anyways enough of the Dyno stuff, again i appreciate everyones input on this matter and hope i get the same honest feedback on any other queries i get, cheers.
You will get the straight story here (like it or not) :cool2:, this is a great community of knowledge!

As far as how i feel when i drive, lets say i get an average 8mpg and about 110-130 miles to a tank and i cant stop driving the thing.
That just about says it all............enjoy! :thumbsup:
 
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