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01-15-2011LAST POST
erhanh wrote
You mean like turbo cars like 135/335? :lol:
Have you looked at the torque curve-its good but not close to the M engine
5erman wrote
Have you looked at the torque curve-its good but not close to the M engine
I was making a joke actually. As far as I remember, the N54 engine has a HP roll off after about 5.5-6k rpm... But I really don't care. Never interested in that engine, or in any kind of turbo engine in general.
erhanh wrote
Here. I think this is a stock dyno result from some forum member
So based on that, I plugged it into a spreadsheet I've got that charts driveshaft torque vs driveshaft RPM to see the shift points easily (for 6MT)...
Image hosted on: members.roadfly.com

In 1st and 2nd shift up at 8300
In 3rd, 8250
In 4th and 5th, 8200

Not exactly a revelation, but seeing it is always nice. And as others have said, no point in shifting down if you're near 5000 in 4th-6th, 4000 in 2nd or 3rd.
Great chart, thanks :thumbsup:
///My5UV wrote
So based on that, I plugged it into a spreadsheet I've got that charts driveshaft torque vs driveshaft RPM to see the shift points easily (for 6MT)...
Image hosted on: members.roadfly.com

In 1st and 2nd shift up at 8300
In 3rd, 8250
In 4th and 5th, 8200

Not exactly a revelation, but seeing it is always nice. And as others have said, no point in shifting down if you're near 5000 in 4th-6th, 4000 in 2nd or 3rd.
wow that is the best chart ever-will come in handy to illustrate to people what you say here-DRIVE shaft torque is a great term-that says it all and thats the only thing that matters. Gearing, engine torque, RPM's and parasitic losses all end up into driveshaft torque and only that is what you go off of. great chart!
Are you able to apply that to some other common comparison cars to the m3 to illustrate the true axle power the m3 puts out in comparison to other cars that may have a "higher" engine output? that would be really interesting
mkoesel wrote
Actually, even for those cars you still want to run it to redline for maximum acceleration, until you start to get to the very top of 3rd gear (> 100 mph).

http://www.m3post.com/forums/showpost.php?p=7829518&postcount=14
Not true. Only in the first two gears do you run the 135/335 to redline. After that it's best to step down 500 rpms per gear. Torque tapers off dramatically after 5500 and the gearing/force is better before redline in the upper gears. To hold to redline is to experience the torque drop at a point when more total force is available by an upshift. Crappy powerband.
5erman wrote
Are you able to apply that to some other common comparison cars to the m3 to illustrate the true axle power the m3 puts out in comparison to other cars that may have a "higher" engine output? that would be really interesting
This actually was done in here: http://www.m3post.com/forums/showthread.php?t=157633

It also has M3 DCT vs MT comparison. :thumbsup:
gr8000 wrote
Actually, its the other way around i.e. pedal to the metal first and then click the (-) paddle
Correct, I had the order wrong. That shows you how often I use that useless technique :)
sensi09 wrote
I was playing around with this tonight along with a quick shift to auto mode to get a downshift. Both would work well if you need a quick downshift, but think I prefer going to auto mode as you don't need to press the accelerator pass the resistance point. Also depending on how hard you mash the throttle in auto, you don't get the lowest possible gear, but rather the second to lowest which is what I would prefer in most situations. I'd have to play with it a bit more, but I also think going to for a downshift via auto mode may be quicker.

The only times I would use either "technique" is when I'm caught off guard and am in a high gear like 7th. Otherwise, if I'm paying attention, I'd rather do a few toggles of the downshift paddle. Before, going from say 6th to 3rd via the three pulls of the paddle would bug me for some reason, but testing each method tonight, I very much prefer it. Just need to be prepared and know what gear you're in to begin with.
It's really up to you and what you're comfortable with. I'm the kind of person that always needs to be in control while driving, so I only use Auto if I'm trying to multitask like eating a burger. I personally find 'D' infuriating, just like any other Automatic transmission - the shifts are unpredictable, and it always seems to put me in the gear I DON'T want to be in. You also can't use engine braking in an emergency situation.

I don't use the kickdown switch very often either, since it's usually excessive. If I need to accelerate quickly (eg merging into traffic) I just flick the paddle a few times, so that I can choose the best gear for the speed I'm currently traveling at and the speed I WANT to be traveling in.

Anyway, all of this talk makes me miss a proper clutch + shifter massively. I will 100% go back to MT for my next car.
The best gear to accelerate in is a pair of good trainers, jeans and a T Shirt. Shirts can be a bit restrictive due to the cuffs and shoes with leather soles can slip off the pedals. Boots are too heavy. Jackets are best avoided as they are cumbersome. A dress is fine if that's what floats your boat.

Avoid stilletos. Apart from the fact that they arent great for gear changes they can make a right mess of your mats.
MVF4Rrider wrote
Not true. Only in the first two gears do you run the 135/335 to redline.
If you read it again, that is basically what I just said.
After that it's best to step down 500 rpms per gear. Torque tapers off dramatica after 5500 and the gearing/force is better before redline in the upper gears. To hold to redline is to experience the torque drop at a point when more total force is available by an upshift. Crappy powerband.
"500 RPMs per gear" is arbitrary. The chart I pointed to accurately shows the *speed* at which you should shift in each gear.
mkoesel wrote
"500 RPMs per gear" is arbitrary. The chart I pointed to accurately shows the *speed* at which you should shift in each gear.
True, I was too lazy to dig out my force charts in which I calculated the actual ideal shift points (a few years ago). But it's close to around 500 per as I recall. Ultimately, what a pain in the arse to have to have in your brain. A turbo biased toward the low end of the power curve does not a performance engine make.