|
Post Reply |
|
Thread Tools | Search this Thread |
07-25-2013, 11:52 PM | #67 |
Brigadier General
134
Rep 3,101
Posts |
I need to say, just because it makes 400ft-lb doesnt mean it MUST make it at redline, or that it has a low redline, or anything
It could make 400ft-lb WAY before redline.. |
Appreciate
0
|
07-25-2013, 11:57 PM | #68 | |||
Brigadier General
134
Rep 3,101
Posts |
Quote:
And sometimes i prefer a burger Apples to oranges haha If you want an analogy that no one can disagree... It's rare-medium rare slow cooked ribeye vs well done week old rump Or mcdonalds vs in'n'out |
|||
Appreciate
0
|
07-26-2013, 12:10 AM | #69 |
Lieutenant
38
Rep 582
Posts |
In case someone feels the need to analyze another 1M, see this video. There was a camera mounted outside at the rear bumper. Granted I shifted when thrust ran out rather than rpms.
|
Appreciate
0
|
07-26-2013, 12:48 AM | #70 | |
Lieutenant General
644
Rep 10,404
Posts |
Quote:
1. If it was easy it would be much more widespread. 2. Torque at the crank is meaningless, you can't feel it and it has nothing to do with performance. Torque at the wheels does matter and the current M3 has plenty of that. The only benefit of massive low rpm torque is if you have a desire to never shift (lazy driving as I call it).
__________________
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK | | Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors | | Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels | | XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit | Last edited by swamp2; 07-26-2013 at 01:05 AM.. |
|
Appreciate
0
|
07-26-2013, 12:51 AM | #71 |
Lieutenant General
644
Rep 10,404
Posts |
So in other words it is basically useless. The idea is to verify the technique vs. a known rpm. Sure you could say we could use speed and gear to get back to rpm but that is approximation and error piled on top of each other.
__________________
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK | | Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors | | Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels | | XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit | |
Appreciate
0
|
07-26-2013, 01:02 AM | #72 | |
Brigadier General
1048
Rep 3,622
Posts |
Quote:
|
|
Appreciate
0
|
07-26-2013, 01:19 AM | #73 | |
Private
13
Rep 72
Posts |
Quote:
__________________
you are a winner
|
|
Appreciate
0
|
07-26-2013, 01:21 AM | #74 | |
Lieutenant
38
Rep 582
Posts |
Quote:
So would a video of a 1M sitting in neutral with the tach showing steady state rpms be of use? If so, what rpm? |
|
Appreciate
0
|
07-26-2013, 01:47 AM | #75 |
First Lieutenant
57
Rep 324
Posts |
If it has the same 8 speed auto tranny, third gear no longer goes to 100. It did in my 335, but in my 535 the gears are a lot closer together.
__________________
13 535i Msport
|
Appreciate
0
|
07-26-2013, 03:01 AM | #76 |
Major
144
Rep 1,399
Posts |
|
Appreciate
0
|
07-26-2013, 03:56 AM | #77 |
Lieutenant Colonel
76
Rep 1,788
Posts |
Great work!! If they offer a manual they I will need one when I get back to the states.
__________________
[SIGPIC][/SIGPIC]
2007 GT3 Clubsport w/CGT buckets in Scotland 2003 CSL, SG, Alcon BBK SOLD 2002 M5, SSII/Blk and bone stock. In storage back home in TX 2008 M3, AW/Blk 6MT, lots of track stuff SOLD |
Appreciate
0
|
07-26-2013, 04:21 AM | #78 | |
Major General
1742
Rep 5,110
Posts |
Quote:
Based on sound analysis there was even articles in F1 magazines on which of the different engine manufacturers reached what max rpm and how much power they had. http://www.grandprix.com/ft/ft00345.html http://asadl.org/jasa/resource/1/jas...s2?bypassSSO=1 http://www.f1technical.net/forum/viewtopic.php?t=2218 |
|
Appreciate
0
|
07-26-2013, 06:10 AM | #79 |
Banned
308
Rep 1,140
Posts
Drives: Something something racecar
Join Date: Feb 2013
Location: Austin, Texas
|
Kinda sounds like my S54. It's still not loud enough though.
|
Appreciate
0
|
07-26-2013, 08:17 AM | #80 |
New Member
0
Rep 9
Posts |
Nice analysis, swamp. Just a few questions cause I am curious...
Why did you choose a hanning window? Did you try a spectrogram to get better time/frequency resolution? Have you tried running the audio through an adaptive FIR filter to remove white noise? Overall it's pretty interesting. I didn't know F1 teams did something similar... |
Appreciate
0
|
07-26-2013, 10:30 AM | #81 | |
Registered
0
Rep 2
Posts |
Quote:
Everyone arguing about it not having a high redline is funny. 7700 rpm is high plain and simple and 7700 on a turbo car that will actually make its peak power somewhat close to that without dropping like it feel off a cliff and still be drivable would be INSANE. For everyone touting about how the Mclaren can do it (also would like to mention that its a MCLAREN SUPERCAR with an engine probably priced as high as an M3) check out its dyno Yep that's peak power at around 7400-7600rpm....It could have a redline of 15000 rpm, if its not making power there why the hell would you spin it that high. that's like saying i have carbon ceramic brakes but i don't track my car... oh wait ... |
|
Appreciate
0
|
07-26-2013, 03:18 PM | #82 | ||
TIM YOYO
1506
Rep 3,282
Posts
Drives: 2013 M3
Join Date: Jun 2010
Location: Vero Beach, FL
|
Quote:
Why did you choose a hanning window? I think he probably chose Hanning window because of the dynamic range of the audio data. Although I looked at rectangular as well, and the plot looked pretty good after I applied a lowpass filter. Did you try a spectrogram to get better time/frequency resolution? Spectrographs of mechanical sounds are really difficult to interpret. I've attached a screenshot of a short section if you're interested in looking at it. This is the region just before the upshift. Have you tried running the audio through an adaptive FIR filter to remove white noise? I'm not really sure what an adaptive FIR filter is. From what I gather, it would required input coefficients that would allow me to narrow the frequency range. I just used a lowpass filter as you can see in my full write-up. ============== My analysis shows a result that's closer to 7400 RPM. If you download my files, you can open the .aup files with Audacity (it's free). Running spectrum analysis on the audio just before the upshift always gives me values closer to 330 Hz, not 350-360 Hz. Not sure why exactly. Full write-up: http://upload.bradlanders.com/bimmer...ound-analysis/ Copy/paste of my Markdown source (links won't work, so you'll have to click here for the full version): Quote:
__________________
His: 2019 R1250GS - Black
Hers: 2013 X3 28i - N20 Mineral Silver / Sand Beige / Premium, Tech Past: 2013 ///M3 - Interlagos Blue Black M-DCT Past: 2010 135i - TiAg Coral Red 6MT ///M-Sport Last edited by bradleyland; 07-26-2013 at 04:33 PM.. Reason: Fuck that attachment |
||
Appreciate
0
|
07-26-2013, 04:21 PM | #83 | |
Lieutenant Colonel
1108
Rep 1,497
Posts |
Quote:
|
|
Appreciate
0
|
07-26-2013, 05:41 PM | #84 |
Captain
232
Rep 679
Posts
Drives: 2025 BMW M2 pending
Join Date: May 2012
Location: Virginia
|
As a side note, I can't stand the upgraded sound system in my E92 M3. It isn't even in the same ball park as the Bang & Olufsen sound system in my previous 2011 Audi S4. I really hope BMW ties up loose ends with the F82 M4, not only in a performance category (usable torque without having to rev into the stratosphere and I am not lazy) but also in a luxury aspect (LED DRL's, nicer interior, better sound system, etc.) The M4 can't come fast enough for me. Like I have said before, I really like my M3, but I feel that I will love the M4. To each their own.
|
Appreciate
0
|
07-26-2013, 07:11 PM | #85 | |
Lieutenant General
644
Rep 10,404
Posts |
Quote:
The only rpm useful really is redline, its a known quantity. Of course that being said limiters are not perfect and I've heard of stock M3's getting to 8460 or so before cut off. I guess that's just another variable in the mix here. M3 and M4 will not have automatic transmissions but rather dual clutch units.
__________________
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK | | Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors | | Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels | | XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit | |
|
Appreciate
0
|
07-26-2013, 08:35 PM | #86 | |
Lieutenant General
644
Rep 10,404
Posts |
Quote:
Although the low pass filtering, fourier techniques and stereo vs. single channel stuff are all completely irrelevant, they just don't affect the answer. My error was recording through speakers rather than internally. Even trying to repeat my process showed considerable error. After switching to recording with Soundflower the shift burble was much more recognizeable visually in the traces. I also got much more recognizable peaks in the spectral results. I agree the observed frequency is right around 330 Hz perhaps with a worst case range of about 325-335 Hz. Thus with a Doppler correction from 90-97 mph this provides an rpm range of about 7250-7550 (with rounding to 50 rpm). This is how science works - basic peer review. Thanks for keeping me on my toes. I will revise my OP in a way to not hide my shortcoming and I'll give you the credit due. Thanks!
__________________
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK | | Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors | | Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels | | XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit | Last edited by swamp2; 07-26-2013 at 10:11 PM.. |
|
Appreciate
0
|
07-26-2013, 09:27 PM | #87 | |
Major General
5522
Rep 7,081
Posts |
Quote:
That said I spent over 10h in the car the last 2 days, all in glorious weather and many on open backroads and I had such a pang of early separation anxiety. This car is bloody awesome, the way it connects into your soul and senses is like a runners high. The new car will need to be exceedingly good to just stay on level, which I think (hope?) it will be. Everything that counts in the current M3 is superb, suspension, steering, chassi, engine, sound, seats, steering wheel, controls, tranny and overall feel. It could be the best 4 door EVER made. |
|
Appreciate
0
|
07-26-2013, 09:30 PM | #88 | |
Private
1
Rep 81
Posts
Drives: '13 X3 3.5, '14 640 GC
Join Date: Feb 2010
Location: Houston, TX & Santa Fe, NM
|
Quote:
|
|
Appreciate
0
|
Post Reply |
Bookmarks |
Thread Tools | Search this Thread |
|
|