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      06-10-2013, 09:34 PM   #106
flinchy
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Drives: E82 135i
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Quote:
Originally Posted by swamp2 View Post
flinchy: The links you provided are entirely irrelevant. The torque curve I am using for the new M4 is nearly exactly like the FACTORY DYNO from BMW for the M5, just adjusted for a bit higher redline. The method to calculate shift points is precisely as I described earlier and this is precisely what CarTest is doing. Until you can offer some proof of your proposition on the F10 M5 gearing/shift points, with a clear description of how the calculation is being performed, you're positively contributing to the discussion here.

Last but not least you should also do some reading on some of the (epic) debates here on the forum about power vs. torque. I used to think about vehicle performance a bit like you are. It is kind of a crutch for truly understanding the power (no pun intended) and simplicity of power (over torque).
i did offer proof

if you hold power flat from 6000-8000RPM, you will ALWAY NO MATTER WHAT shift at redline for maximum acceleration, as ONLY there will the next gear provide better acceleration

in fact, even the factory N54 powered cars dyno indicate that peak acceleration is ALWAYS redline, it's only once tuned that it shifts from redline to upper midrange.

until YOU can show any evidence otherwise, that's the fact...

heck.. i just plugged a stock F10 dyno into MULTIPLE calculators (Like the ones i posted) and STOCK it's redline shifting, it's not until tuned (like the graph i posted) that the midrange overtakes.


calculation being performed via any number of calculators (spreadsheets etc.) that use various points of torque curves + gear ratios+FD to work out at what point it's more effective to change

i even posted links to EXACTLY what i was using.


you know.. that and logic, logic goes a long way.

Quote:
Originally Posted by swamp2 View Post
Last but not least you should also do some reading on some of the (epic) debates here on the forum about power vs. torque. I used to think about vehicle performance a bit like you are. It is kind of a crutch for truly understanding the power (no pun intended) and simplicity of power (over torque).
LOL it sounds like you're the one lacking understanding

you should google:

'Why-horsepower-torque-quot-changes-quot-dynos-quot-read-low-quot-peak-torque-is-not-when-you-accelerate-hardest-and-gearing-matters'

an article on 'the other site'



a crutch for truly understanding power? yeah no, more like how power actually works

power is torque over time (ie at an RPM), torque is power without time (hence torque is also called a 'moment of force')
anyone who disagrees with the above is simply wrong, as they can't prove anything otherwise (and conversely, proof in abundance for the CORRECT case)

torque as read on a dyno graph is without gearbox+final drive multiplication ('at the flywheel' even though it's not a true 'flywheel' value)

i studied mechanics of force at university, FWIW.. one of the few subjects in that degree i didn't fail HAH


ED: i can tell you know a LOT.. and i'm not debating anything else you're saying, as i'll just assume you're correct in that

but you seem to be lacking core understanding of torque+power+gearing+acceleration etc relationship.

Last edited by flinchy; 06-10-2013 at 10:18 PM..
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