Whats the best shift RPM for best acceleration?
01-05-2007, 10:36 PM
#22
Senior Members
Join Date: Oct 2004
Location: Johannesburg, South Africa
Posts: 299
Likes: 0
Received 0 Likes
on
0 Posts
I wish the BMW engineer red line shift was also true in the diesels.
Unless my butt dyno needs calibrating, there is so much time wasted outside the torque peak getting to the red line and then recovering in the next gear that it feels ridiculous, it's even worse in DS mode.
I find I get the best in D or M modes.
Unless my butt dyno needs calibrating, there is so much time wasted outside the torque peak getting to the red line and then recovering in the next gear that it feels ridiculous, it's even worse in DS mode.
I find I get the best in D or M modes.
01-06-2007, 12:03 AM
#23
Senior Members
Join Date: Apr 2006
Location: UK
Posts: 3,097
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by dlevi67' post='374096' date='Jan 5 2007, 10:53 PM
I think it's pretty clear that torque in a rotational system that transfers the rotational motion into a (roughly) rectilinear one is force... and viceversa. I'm not sure what is more analogical than this.
ABC
01-06-2007, 12:34 AM
#24
Contributors
Join Date: Jul 2006
Location: Oxfordshire, UK
Posts: 1,180
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: E61 535d Apr 05. UK spec + Media Pack, Luxury Pack & Visibility Pack
Aahhh - I missed the subtle irony, then. The deadpan expression of your post fooled me. 
01-06-2007, 12:40 AM
#25
Contributors
Join Date: Aug 2005
Location: Austin TX
Posts: 6,554
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2014 X5 xDrive 5.0 M Package Carbon Black Metallic/2008 M Roadster Imola Red
Originally Posted by Znod' post='374077' date='Jan 5 2007, 02:45 PM
The idea is to minimize the decrease in road torque when shifting (or maximize the increase). Check the musing out on Thread1 and Thread2. You'll have to search around a bit, but there are 4 or 5 posts on these threads applying optimal shift theory. And, optimal shift theory says that redline is not always optimal in any given gear or car. Unfortunately, the Step doesn't give us the chance to find out what is optimal experimentally. Most of my calculation suggest that redline, or close to it, is optimal for the 545i Step in all gears.
01-06-2007, 12:40 AM
#26
Contributors
Join Date: Jul 2006
Location: Oxfordshire, UK
Posts: 1,180
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: E61 535d Apr 05. UK spec + Media Pack, Luxury Pack & Visibility Pack
Originally Posted by streak' post='374218' date='Jan 6 2007, 07:36 AM
I wish the BMW engineer red line shift was also true in the diesels.
Unless my butt dyno needs calibrating, there is so much time wasted outside the torque peak getting to the red line and then recovering in the next gear that it feels ridiculous, it's even worse in DS mode.
I find I get the best in D or M modes.
Unless my butt dyno needs calibrating, there is so much time wasted outside the torque peak getting to the red line and then recovering in the next gear that it feels ridiculous, it's even worse in DS mode.
I find I get the best in D or M modes.
Having said that - and having driven 530i and 530d back to back - it sounds like your turbo may have a few problems. Turbo lag under hard acceleration should not be that bad (should not be there at all), nor should there be a lot of time between torque peak and redline
01-06-2007, 12:57 AM
#27
Senior Members
Join Date: Apr 2006
Location: UK
Posts: 3,097
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by dlevi67' post='374236' date='Jan 6 2007, 09:34 AM
Aahhh - I missed the subtle irony, then. The deadpan expression of your post fooled me.
I'm disappointed that you had the faintest glimmer that I didn't know what an analogy was. Especially when I introduced the idea into the thread!
That's egregious!
ABC
Thread
Thread Starter
Forum
Replies
Last Post