Throttle Response/Sport Mode Question - The Unofficial BMW M5 Messageboard (m5board.com)

livenupe · 12th April 2002, 03:29

I was under the impression that the improved throttle response effect that we get from the sport mode is the result of compressing the full range of the accelerator pedal into a shorter range. In other words, if moving the accelerator pedal in 20% gives you 20% throttle in the regular mode, I would expect moving the accelerator pedal 20% to yield 25% (or something greater than 20%) throttle while in sport mode.

While driving in to work this morning, I decided to test my understanding of how the sport mode works using the following "experiment".

While in the regular (non-sport) mode, I put the car in neutral and steadied the engine at 3,000 rpm. I then pressed the sport button and expected to see the tach move up. Well to my surprise, nothing happened. While holding the accelerator pedal steady, the sport mode button had no impact on the engine speed.

What am I missing??? I obviously don't have a thorough understanding of how the sport mode button impacts throttle response. Was my "experiment" flawed or is the car programmed so the sport mode button is inactive when the car is in neutral?

PhilSeastrand · 12th April 2002, 03:52

My understanding is that non-sport mode is non-linear at the bottom of the throttle range and that the sport mode makes it almost linear. Therefore 20% pedal position == 20% is sports mode but only 15% in non-sport mode.

Try your experiment again at 1500 RPM and 2000 RPM -- I bet you'll see a different result.

I also understand that the Dinan chip mod brings the non-sport mode almost in line with the sport mode.

Steve Morling · 12th April 2002, 04:01

I agree with Phil. My observation is that at low revs, switching Sport on will kick the revs up. Try it (on an empty stretch of road or parking lot) in 1st gear: hold steady throttle at ~1500 revs and put Sport on. You get a nice little kick.

livenupe · 12th April 2002, 04:35

I'll try it on the way home tonight and see if it makes a difference.

Danish · 12th April 2002, 04:47

The sport mode shorten the throttle response time by removing a built-in lowpass filter that makes the car more driveable in city traffic (Normal mode). It is actually more complex than that - we are talking about two different transfer functions, mathematically speaking.

greg · 12th April 2002, 07:58

I turn it on all the time while holding about 1/8 throttle, accelerating in 1st or 2nd. You get a nice little kick in the back.

2001's X5/Z8 · 15th April 2002, 02:46

Does the sport mode better the performance numbers???? or does it make the car "feel" faster????

AndyMenard · 15th April 2002, 03:55

The car is not actually faster with Sport mode on, it just feels that way because of the more aggressive fuel application at a given accelerator pressure. Sport mode shortens the time needed (again at a given pressure from your right foot) to open the throttle butterflies and inject fuel into the cylinders... I think I read somewhere that it opens them at around 120 milliseconds (as opposed to around 250-300+ milliseconds with sport mode off).

Therefore, throttle reponse it better with Sport mode ON.

ACHE · 15th April 2002, 06:37

I recently had the Dinan software programmed into my M5 and I'm
wondering if there is any improved or different throttle response in
Sport mode. I do feel some difference in normal mode driving but I
usually put the car into sport mode all the time. Bottom line, is there any difference with the software in sport mode. Thanks

VanCooper · 15th April 2002, 10:52

Quote:

Originally posted by livenupe
While in the regular (non-sport) mode, I put the car in neutral and steadied the engine at 3,000 rpm. I then pressed the sport button and expected to see the tach move up. Well to my surprise, nothing happened. While holding the accelerator pedal steady, the sport mode button had no impact on the engine speed.

What am I missing??? I obviously don't have a thorough understanding of how the sport mode button impacts throttle response. Was my "experiment" flawed or is the car programmed so the sport mode button is inactive when the car is in neutral?

I did the same experiment a while ago and sport mode definitly brought up the revs while keeping a constant pressure on the gas pedal...I found it pretty interesting

PhilSeastrand's right though, keep it in the 1500's to 2000's rpm to really hear the difference

livenupe · 20th April 2002, 02:32

OK, I'm really confused now. I steadied the engine at 2000 rpm and the revs actually DROPPED when I engaged the sport button. What gives?