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      02-04-2009, 03:54 AM   #67
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I believe the 1:1 ratio "myth" on dynos relates to Dynojets, that's what I was told anyway...

See http://www.roymech.co.uk/Useful_Tabl...fficiency.html - looking at the formulas for helical gears, you can see that gear ratio does have an impact on gear efficiency - the higher the gear ratio, the greater the efficiency.

So you should see higher figures for a run in 3rd gear, vs a run in 4th gear. On my old RS4 it dyno'ed 320WHP in 3rd gear but only 260WHP in 4th gear, on a Dynapack. The operator thought the Quattro transmission was causing these weird differences as the front/rear power distribution was not consistent and would fluctuate wildly.
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      02-04-2009, 04:42 AM   #68
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Quote:
Originally Posted by PencilGeek View Post
Let me see if I can destroy this myth without starting a flame war. This myth probably wouldn't even exist if more people understood how the power is transmitted from the motor to the wheels. I think this myth continues to propogate -- mostly -- because it sounds like it makes sense on the surface and most people don't understand how power is transmitted. So they blindly accept it, and the myth continues to propogate. So let's see if I can dispell it -- at least for the 20 people who may read this message.

Regardless of torque and RPM, some value of power exists at the flywheel. The flywheel causes the primary shaft of the transmission to spin. The gear on the primary shaft has some number of teeth on it, and meshes with another gear on the secondary shaft that has a different number of teeth on it. This is how you get a gear ratio: 87 teeth on the primary divided by 55 teeth on the secondary equals a 1.58:1 gear ratio (87/55=1.58). Obviously a 1:1 gear ratio has the same exact number of teeth on the primary and secondary shafts.

The drive shaft is connected to the secondary shaft of the transmission. But before getting to the wheels, there is one more conversion to take place: the final drive ratio. The secondary shaft/drive shaft spins a primary gear in the final drive, which in turn causes a secondary gear to spin as well. Once again, divide the number of teeth on the primary shaft with the number of teeth on the secondary shaft, and you get the final drive ratio. In the case of the M3, there are 100 teeth on the primary, and 26 teeth on the secondary giving a 3.8462:1 final drive ratio (100/26=3.8462).

Since both of these gears reduce the motor RPM to wheel/hub RPM, they BOTH act as torque multipliers. It's important to understand that BOTH gears act as torque multipliers: the transmission gear ratio AND final drive ratio act as torque multipliers -- not just the transmission gear ratio. It's easy to calculate the combined torque multiplier, as it's simply the gear-ratio x final-drive-ratio. In this case, 1.58 x 3.8462 = 6.084.

To compensate for the torque multiplier, you simply divide the measured results by the torque multiplier to obtain the actual results. In the case of a 3rd gear run on the M3, divide the measured results by 6.084 to obtain the actual results. If you look at the dyno chart, you will see they did exactly that. You will see '6.084' in the bottom right corner of the dyno chart. That was the torque DIVISOR from the measured results. If it weren't there, you'd be seeing over 2400 horsepower from this motor.

The myth:
Regardless of which dyno you use, you are always getting a torque multiplier because whichever gear you choose is always being run through and multiplied by the final drive ratio. The myth states that you need to run as close to 1:1 as possible -- completely ignoring that a final drive ratio even exists. Well the bad news for people who don't think for themselves: a final drive ratio does exist, and always acts as a torque multiplier itself. Eliminating the torque multiplying effects is as simple as dividing the measured results by this value.

So at least for the 20 people reading this thread, I hope you'll now understand how this works...and why it doesn't matter.

Oh, and for those of you still tempted to say that you need to run in 5th gear (1:1), think again. Your speed limiter would kick in before your dyno run is over...and completely invalidate your results.

So under ''No Speed Restrictions'' requirements what is the Best Gear to Dyno the M3...?

1)3rd
2)4th
3)5th
4)Any...?


P.S. Stil trying to find out why my car is putting (327 whp With Rpi Scoops,BMC Filter,and ACS Rear Mufflers heheheheh,maybe we should recalculate some factors on the Dyno se we can have percise resaults according to the factory claims)
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      02-04-2009, 05:02 AM   #69
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I ned tell some secrets about ECU flashing when I read here.

First of all I would like to excuse my bad english.

1. Is BMW able to notice a ECU reflash?

Yes definitly yes! Since they have all CAN BUS OBDII interfaces and the new generation of Bosch ECUs MSSxx. BMW is reading out the ECU every time and they are sending the data to a central BMW server where those data records are randomly checked. I would say about every 10th of it. And they can defenetly see the speedlimiter and some other stuff.

2. dynos

They have to be done in 5th gear. Power loss on these kind of dynos you talk about are between 8-12%. A complete reflash has no speedlimiter. So if we go on the dyno we are turnig off the speed limiter before and after the reflash.

3. bhp

We are working together with German ingeneurs from Bayrische Motorenwerke. And the highest numbers you can expect form a Dyno is +30PS (I don't know in bhp and torque). That is the highest number which can be constantly reproduced and it is made in Germany together with a former Alpina developer and he is working together with us. Those low 17ps you allways hear about are made with a old ECU flash tool. And those are especially sold outside Germany because you can't Do certain things like the speed limiter and it was the first one on the market. So sometimes it works and sometimes not.

We had to pay a whole lot of money to get that new ECU tool ready to work with. There are a few tuners who worked together to make it happen.
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      02-04-2009, 05:11 AM   #70
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Quote:
Originally Posted by Boris@kks-performance.com View Post
2. dynos

They have to be done in 5th gear. Power loss on these kind of dynos you talk about are between 8-12%. A complete reflash has no speedlimiter. So if we go on the dyno we are turnig off the speed limiter before and after the reflash.

I will let PG reply to your other statements, as I dont know such details, I was going by what I was told by many people, including BMW service!

However, How would I dyno before the reflash in 5th gear, when surely I would run out of speed because I would obviously hit the speed limiter? Prior to the reflash of the ECU, the speed limiter would kick in, in 5th gear on the dyno. YES, your right after the reflash I would be able to do my run on the dyno in 5th gear. But not before....sooo what sort of comparision would that be?? Not a very good one.

So what you say...makes no sense!
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      02-04-2009, 07:28 AM   #71
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Quote:
Originally Posted by slammedm3 View Post
I will let PG reply to your other statements, as I dont know such details, I was going by what I was told by many people, including BMW service!

However, How would I dyno before the reflash in 5th gear, when surely I would run out of speed because I would obviously hit the speed limiter? Prior to the reflash of the ECU, the speed limiter would kick in, in 5th gear on the dyno. YES, your right after the reflash I would be able to do my run on the dyno in 5th gear. But not before....sooo what sort of comparision would that be?? Not a very good one.

So what you say...makes no sense!
Yeah right, but i think a private Dyno Run never makes sense. You have to trust in the feel of driving. Different Dynos are making different numbers. A before and after Dyno has to be made at the same day under the same conditions to be convinced.

And I was talking about the Dyno Runs we are doing.
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      02-04-2009, 08:02 AM   #72
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Quote:
Originally Posted by Boris@kks-performance.com View Post
Yeah right, but i think a private Dyno Run never makes sense. You have to trust in the feel of driving. Different Dynos are making different numbers. A before and after Dyno has to be made at the same day under the same conditions to be convinced.

And I was talking about the Dyno Runs we are doing.
Well...that would be impossible seeing as I had to send my ECU to Miami for the reflash.
But I did my second dyno (after reflash from AA) on the same dyno, with the same gear ratios and
Same factors. And the outside temperature was quite close too! So I think I did the best I could!

And your right.. All that matters is the feel of the car. And all I can say is the feel of the car has changed tremendously
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      02-04-2009, 09:06 AM   #73
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Quote:
Originally Posted by Boris@kks-performance.com View Post
I ned tell some secrets about ECU flashing when I read here.

First of all I would like to excuse my bad english.

1. Is BMW able to notice a ECU reflash?

Yes definitly yes! Since they have all CAN BUS OBDII interfaces and the new generation of Bosch ECUs MSSxx. BMW is reading out the ECU every time and they are sending the data to a central BMW server where those data records are randomly checked. I would say about every 10th of it. And they can defenetly see the speedlimiter and some other stuff.

Only field reps have these interfaces. I have never heard of a single issues of an ECU on an NA car causing any issues. The members on the forum are referring to our BMW dealerships that service our cars, not BMW corporate centers. (who still do not read the actual files on the ECU, they normally just upload new firmware completely ignoring what was on the ECU to begin with....unless you are dealing with an N54 car...



2. dynos

They have to be done in 5th gear. Power loss on these kind of dynos you talk about are between 8-12%. A complete reflash has no speedlimiter. So if we go on the dyno we are turnig off the speed limiter before and after the reflash.

5th gear will overheat a car on a dyno......

3. bhp

We are working together with German ingeneurs from Bayrische Motorenwerke. And the highest numbers you can expect form a Dyno is +30PS (I don't know in bhp and torque). That is the highest number which can be constantly reproduced and it is made in Germany together with a former Alpina developer and he is working together with us. Those low 17ps you allways hear about are made with a old ECU flash tool. And those are especially sold outside Germany because you can't Do certain things like the speed limiter and it was the first one on the market. So sometimes it works and sometimes not.

We had to pay a whole lot of money to get that new ECU tool ready to work with. There are a few tuners who worked together to make it happen.

Everyone had to pay a lot of money for the new "tools" to get into both sides of the DME's since BMW decided to lock the BDM... You are correct a few companies were actually flashing half of the ECU and claiming to offer an entire ECU reflash, we offer a complete reflash of the DME which includes both sides of the ECU.
Notes above in red..
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      02-04-2009, 12:01 PM   #74
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Only field reps have these interfaces. I have never heard of a single issues of an ECU on an NA car causing any issues. The members on the forum are referring to our BMW dealerships that service our cars, not BMW corporate centers. (who still do not read the actual files on the ECU, they normally just upload new firmware completely ignoring what was on the ECU to begin with....unless you are dealing with an N54 car...

O.K. I must say it could be a German (European) Problem. What I mean is that they can, not that they will notice a change. In Germany every Dealer has to have those interfaces.


5th gear will overheat a car on a dyno......

Never overheated on a Maha Dyno in 5th gear. Those are the reference Dynos with huge Air vents. Those are the ones we are using.

Everyone had to pay a lot of money for the new "tools" to get into both sides of the DME's since BMW decided to lock the BDM... You are correct a few companies were actually flashing half of the ECU and claiming to offer an entire ECU reflash, we offer a complete reflash of the DME which includes both sides of the ECU.


I am sure you guys are doing good work over there. It was not against your company. It was just in general because many companies are trying to tell people that BMW will not notice anything.

Here in Germany you get in deep trouble right now if try to flash 335i without a permission. That is an result of all those ebay flashes all over the world. I think they will try to do it like that in the near future also in the USA.
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      02-04-2009, 12:35 PM   #75
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Out of curiosity Pencilgeek... Do you happen to be a rocket scientist? lol

I definately enjoy reading your posts.
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      02-04-2009, 12:58 PM   #76
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Quote:
Originally Posted by PencilGeek View Post



5th gear has less mechanical efficiency. If you want accurate results, you won't use 5th gear.

If you use 3rd gear you are getting a result that is easier to be manipulated by wrong calculations of the computer. We are always trying use as nearly possible 1:1 ratio.





You are only speculating here, and trying to promote your own products. You have no idea which people have the full DME flash capabilities...and which don't.

Please read my post above. I am not trying to promote my product. 20% percent s full DME and rest is half on the market.




People who prefer scientifically accurate results don't rely in their 'feelings' to measure horsepower. Instead, they rely on instrumentation. It's not always possible to do all dyno testing on the same day. And when it's not possible, that's why the SAE 1349 horsepower correction formulas exist. Those formulas are meant to correct for atmospheric differences measured from one day to the next, and from one set of atmospheric conditions to the next.

I Know all of that. And americans do love Dynos.

But you never get the same result. And a company allways chooses out the best result for promotion. We Do have DIN horsepower correction. But everyone is able manipulate his Dyno.
Please read inside the quote
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      02-04-2009, 01:04 PM   #77
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How has your fuel consumption been affected?
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      02-04-2009, 01:53 PM   #78
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Originally Posted by badfish View Post
How has your fuel consumption been affected?

I will let you know when I finish my next tank of gas, so far, looking good. more or less the same!
But im curious to see myself!
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      02-04-2009, 02:01 PM   #79
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Quote:
Originally Posted by Boris@kks-performance.com View Post
Only field reps have these interfaces. I have never heard of a single issues of an ECU on an NA car causing any issues. The members on the forum are referring to our BMW dealerships that service our cars, not BMW corporate centers. (who still do not read the actual files on the ECU, they normally just upload new firmware completely ignoring what was on the ECU to begin with....unless you are dealing with an N54 car...

O.K. I must say it could be a German (European) Problem. What I mean is that they can, not that they will notice a change. In Germany every Dealer has to have those interfaces.


5th gear will overheat a car on a dyno......

Never overheated on a Maha Dyno in 5th gear. Those are the reference Dynos with huge Air vents. Those are the ones we are using.

Everyone had to pay a lot of money for the new "tools" to get into both sides of the DME's since BMW decided to lock the BDM... You are correct a few companies were actually flashing half of the ECU and claiming to offer an entire ECU reflash, we offer a complete reflash of the DME which includes both sides of the ECU.


I am sure you guys are doing good work over there. It was not against your company. It was just in general because many companies are trying to tell people that BMW will not notice anything.

Here in Germany you get in deep trouble right now if try to flash 335i without a permission. That is an result of all those ebay flashes all over the world. I think they will try to do it like that in the near future also in the USA.
No worries, I undertand completely. I understand jail time is even involved with flashing ECU's in Germany.

Maybe you should come state side
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      02-04-2009, 02:02 PM   #80
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Quote:
Originally Posted by slammedm3 View Post
I will let you know when I finish my next tank of gas, so far, looking good. more or less the same!
But im curious to see myself!
Wont be able to noticed a difference, if anything it should get better, assuming you were driving the same .... at the end of the day your right foot will determine that....

...... now with the X pipe upgrade fuel mileage will probably be a bit less since you wont be able to control that right foot
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      02-04-2009, 02:12 PM   #81
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PG one thing that does affect your results on the Dynapack seems to be the ramp rate (i.e. the load the dyno will apply) - have you figured what this should be for M3 in third gear to get as close as possible to real world load that is applied on the road?
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      02-04-2009, 03:00 PM   #82
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Quote:
Originally Posted by PunjabiM3 View Post
My thoughts exactly. I'm guessing that dyno runs high. I highly doubt a pulley, muffler, and chip will yield 40-50whp as most e9x M3's run around 340whp.
Actually it seems about right to me. If you look at the results that PG gained by these individual mods, 40whp isn't out of the question.
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      02-04-2009, 03:08 PM   #83
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Quote:
Originally Posted by ChitownM3 View Post
Actually it seems about right to me. If you look at the results that PG gained by these individual mods, 40whp isn't out of the question.

Generally they're not additive, such that three individual mods that would give you 15 bhp each if done alone will probably add up to 32 bhp rather than 45.

Dave
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      02-04-2009, 03:08 PM   #84
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Slammed... if you now add the AA Xpipe with high flow cat you should hit over 410 whp... Now that is sick !
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      02-04-2009, 03:21 PM   #85
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Originally Posted by M3 Montreal View Post
Slammed... if you now add the AA Xpipe with high flow cat you should hit over 410 whp... Now that is sick !
haha I know!

That would be awesome...Im working on it!
But honestly, after the ECU - Im reallllly happy with the power in my car for the first time. The pulleys made a huge difference when I first installed them a couple months ago - but the ECU was by far the best mod Ive done (performance wise).
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      02-04-2009, 04:06 PM   #86
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Quote:
Originally Posted by Active Autowerke View Post
Wont be able to noticed a difference, if anything it should get better, assuming you were driving the same .... at the end of the day your right foot will determine that....

...... now with the X pipe upgrade fuel mileage will probably be a bit less since you wont be able to control that right foot
You're right on that comment. My fuel mileage sucks right now but mainly due to my driving
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      02-04-2009, 07:25 PM   #87
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Quote:
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You're right on that comment. My fuel mileage sucks right now but mainly due to my driving
Time for you to do a dyno.....you're my only hope, as I live 500 miles from any dyno!!
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      02-05-2009, 03:03 AM   #88
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Quote:
Originally Posted by PencilGeek View Post
The OP used an 11-second ramp time (if I remember his dyno charts correctly). If he went to 16 seconds, I'll bet you'd see 3-5 more HP in the results.

WOW!
Its actually unbelievable how much you know about this stuff!

By the way, good to know...because I wanted to break the 400 whp number.
Next time, well do the 16 seconds ramp time!

(PS. What is ramp time??)
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