Digits skip under hard acceleration
03-08-2006 | 08:18 AM
#1
Thread Starter
The Prototype
Joined: Jan 2006
Posts: 1,793
Likes: 0
Digits skip under hard acceleration
Just noticed today, was coming on a on ramp at full tilt and looked down briefly noticed the digits skip pretty bad in 1st and 2nd gear. Like 10-16-21-28-31-26-32-38-44-50-54-58-62 etc... not exactly like this but you get the picture.
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
Last edited by DailyDriver2k5; 03-08-2006 at 08:20 AM.
03-08-2006 | 08:30 AM
#2
Originally Posted by DailyDriver2k5
Just noticed today, was coming on a on ramp at full tilt and looked down briefly noticed the digits skip pretty bad in 1st and 2nd gear. Like 10-16-21-28-31-26-32-38-44-50-54-58-62 etc... not exactly like this but you get the picture.
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
03-08-2006 | 08:56 AM
#3
Registered User
Joined: Jan 2006
Posts: 164
Likes: 0
^^^
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
03-08-2006 | 09:25 AM
#4
Originally Posted by ALP22
^^^
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
03-08-2006 | 11:34 AM
#6
Registered User
Joined: Apr 2003
Posts: 25
Likes: 0
Digital speedometer has a certain refresh interval. Let's say it refreshes every 1/2 second. If your speed changes from 50 mph to 53 mph within that 1/2 second, then you will see the speedo jumping from 50 directly to 53.
Besides, speedos on cars just provides estimates. Accurate measurements are taken by using radar, laser and other external sensors.
Besides, speedos on cars just provides estimates. Accurate measurements are taken by using radar, laser and other external sensors.
03-08-2006 | 12:26 PM
#7
Insanely Yellow
Joined: Jul 2004
Posts: 2,093
Likes: 3
From: Buffalo Grove IL
They use a device called an "optical 5th wheel" and they back that up with a pro-level g-tech like performance meter that measures with GPS and accelerometers. The optical 5th wheel "watches" the ground go by and measures the rate at which it is going by.
I have an amateur, first generation gTech and works like an absolute charm for 0-60 measurements -
I have an amateur, first generation gTech and works like an absolute charm for 0-60 measurements -
03-08-2006 | 01:51 PM
#11
Registered User
Joined: Mar 2005
Posts: 1,587
Likes: 1
Originally Posted by Three37ny
Anyone know? I think I heard that on the Miata, at least, it reads a bit faster than you're going.
03-08-2006 | 02:07 PM
#12
Mmmmm... Rotary Donut
Joined: Nov 2003
Posts: 2,376
Likes: 4
From: Lake in the Hills, IL (NW Chicago Burbs)
Originally Posted by DailyDriver2k5
Just noticed today, was coming on a on ramp at full tilt and looked down briefly noticed the digits skip pretty bad in 1st and 2nd gear. Like 10-16-21-28-31-26-32-38-44-50-54-58-62 etc... not exactly like this but you get the picture.
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
Got back in town and did a few brisk acceleration from the lights and noticed it again. Makes me wonder, how did the car mags get a accurate time from 0-60? I think i may seen the actual number "60" once or twice during my test. Usally around the ,57, 58, 59 mph it would skip to 62, 63 mph.
So could are cars be a hair quicker or slower than the estimated 5.9 ticks?
03-08-2006 | 05:27 PM
#13
Club Marbles Member
Joined: Jul 2005
Posts: 3,252
Likes: 0
From: DFW, TX
Originally Posted by ALP22
^^^
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
03-08-2006 | 05:40 PM
#15
Pistons are Over Rated
Joined: Sep 2005
Posts: 152
Likes: 0
From: Orlando, FL
I never paid attention to it on my test drive, every time I looked down, I was at a constant speed, so I figured it was pretty accurate. Typically there is a margin or error built into any speedometer, whether it is digital or not. The 1.5-2% number sounds about right, makes more of a difference the faster you go.
Since I have had the car for a while now, I have noticed the skipping, but I think it does do a good job catching up. I have done some experiments to see how fast I can get it to skip and the best I have done is 6mph with a WOT 2nd gear run on flat surface starting at 5500rpm. I did also notice that sometimes when you are moving at a constant speed and then get on it to merge in traffic or onto a hi-way that it will sometimes lag a little before it starts catching up. I have grown to like the digital speedometer however and the fact that the passenger can not read it
Since I have had the car for a while now, I have noticed the skipping, but I think it does do a good job catching up. I have done some experiments to see how fast I can get it to skip and the best I have done is 6mph with a WOT 2nd gear run on flat surface starting at 5500rpm. I did also notice that sometimes when you are moving at a constant speed and then get on it to merge in traffic or onto a hi-way that it will sometimes lag a little before it starts catching up. I have grown to like the digital speedometer however and the fact that the passenger can not read it
03-08-2006 | 06:16 PM
#19
Insanely Yellow
Joined: Jul 2004
Posts: 2,093
Likes: 3
From: Buffalo Grove IL
Originally Posted by ALP22
^^^
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
Like he said.
There's no way some guy with a stopwatch in the passenger seat watching the speedo is accurate enough for split second differences in 0-60 times. They use radar, lasers and a nuch of other complicated stuff at the track. Of course, none of these can overcome the fact that black is the fastest color
Lightning Yellow that is ...
)
