Go Back   EcoModder Forum > EcoModding > Off-Topic Tech
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-31-2007, 01:32 PM   #1 (permalink)
Giant Moving Eco-Wall
 
DifferentPointofView's Avatar
 
Join Date: Dec 2007
Location: The Dale, IL (or A-Dale)
Posts: 1,120

The Jeep! - '95 Jeep Grand Cherokee ZJ Laredo
90 day: 23.75 mpg (US)

The Caliber - '07 Dodge Caliber R/T
90 day: 30.6 mpg (US)

The 'Scort - '98 Ford Escort LX
Thanks: 0
Thanked 7 Times in 6 Posts
Speedometer Problometer

So I always have questioned the accuracy of my Speedometer, and other people have told me that I was driving 50mph and my speedo said 55. At 60 they tell me I'm driving 55. But I followed my Mom in her caliber (and I know that speedo is incredibly accurate, from passing a speed sign). and she went 55 and mine said 55. So I'm beginning to question how accurate it is. I've passed one of those speed signs one time, and my speedo said 45 but the sign said I was doing 43. I'm guessing it's about 5mph off at 60.

Question is, how do I test this? I'm just glad its overrating my speed, and not underrating it. I know that the best way would probably be take it to a dyno, which I have no idea where one would be. And how much would it cost to dyno the thing?

__________________


Yea.. I drive a Jeep and I'm on a fuel economy site, but you just wouldn't understand... "It's a Jeep thing!" *Jeep Wave*

Did I Use Too Many Abbreviations? Here's The Abbreviations List
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-31-2007, 02:25 PM   #2 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,447

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 122 Times in 90 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
If you had a gps it would be pretty easy, but there are a few tricks:

1. Go out on the highway and use the mile markers and compare to your odometer / trip meter and find the difference.

2. Plot a route on google maps, follow it, and see the difference from the google maps mileage and your odometer / trip meter.

Most people's speedos are a bit off, good luck,
  Reply With Quote
Old 12-31-2007, 02:26 PM   #3 (permalink)
Giant Moving Eco-Wall
 
DifferentPointofView's Avatar
 
Join Date: Dec 2007
Location: The Dale, IL (or A-Dale)
Posts: 1,120

The Jeep! - '95 Jeep Grand Cherokee ZJ Laredo
90 day: 23.75 mpg (US)

The Caliber - '07 Dodge Caliber R/T
90 day: 30.6 mpg (US)

The 'Scort - '98 Ford Escort LX
Thanks: 0
Thanked 7 Times in 6 Posts
I have GPS, so.. there we go! I've done a mile marker thing to see if the odometer is also reading wrong and it was pretty accurate.

EDIT: how do I adjust the speedo if I find it to be off? is there a calibration thing I can do?
__________________


Yea.. I drive a Jeep and I'm on a fuel economy site, but you just wouldn't understand... "It's a Jeep thing!" *Jeep Wave*

Did I Use Too Many Abbreviations? Here's The Abbreviations List
  Reply With Quote
Old 12-31-2007, 02:32 PM   #4 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,447

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 122 Times in 90 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
If it is off, then there's really not much you can do about it. On older cars I've heard they are often off because the manufacturers only made one speedo for various cars with different wheel sizes and things...So it's likely not adjustable.
  Reply With Quote
Old 12-31-2007, 02:36 PM   #5 (permalink)
Giant Moving Eco-Wall
 
DifferentPointofView's Avatar
 
Join Date: Dec 2007
Location: The Dale, IL (or A-Dale)
Posts: 1,120

The Jeep! - '95 Jeep Grand Cherokee ZJ Laredo
90 day: 23.75 mpg (US)

The Caliber - '07 Dodge Caliber R/T
90 day: 30.6 mpg (US)

The 'Scort - '98 Ford Escort LX
Thanks: 0
Thanked 7 Times in 6 Posts
Well I heard that you can adjust a speedo or tach to accommodate a different speed, ie. take a speedo and adjust it for every 2mph it reads 1mph, so that you can read it as if it says 120 it's really 240. Although those were after market speedo's and tachs, so I'm not sure. wouldn't the cable be adjustable?
__________________


Yea.. I drive a Jeep and I'm on a fuel economy site, but you just wouldn't understand... "It's a Jeep thing!" *Jeep Wave*

Did I Use Too Many Abbreviations? Here's The Abbreviations List
  Reply With Quote
Old 12-31-2007, 02:44 PM   #6 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,447

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 122 Times in 90 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
On my old cable speedo (electronic now) I know it wasn't adjustable. I spose you could have put a different gear on the speedo itself inside the tranny, but honda only made one gear, so you'd have to get one custom made,
  Reply With Quote
Old 12-31-2007, 02:49 PM   #7 (permalink)
Giant Moving Eco-Wall
 
DifferentPointofView's Avatar
 
Join Date: Dec 2007
Location: The Dale, IL (or A-Dale)
Posts: 1,120

The Jeep! - '95 Jeep Grand Cherokee ZJ Laredo
90 day: 23.75 mpg (US)

The Caliber - '07 Dodge Caliber R/T
90 day: 30.6 mpg (US)

The 'Scort - '98 Ford Escort LX
Thanks: 0
Thanked 7 Times in 6 Posts
I'll consult my grandpa, he was a mechanic for over 30 years, I don't know if mine uses a cable one or not, but a lot of things on this SUV were electronic, and that the Idle speed isn't adjustable. I mean, it was a 30grand vehicle when it came out, I'm sure they would use more electronic stuff since it was supposed to be a luxury SUV. I'm just glad I got mine for 2grand It WAS the 90's tho...
__________________


Yea.. I drive a Jeep and I'm on a fuel economy site, but you just wouldn't understand... "It's a Jeep thing!" *Jeep Wave*

Did I Use Too Many Abbreviations? Here's The Abbreviations List
  Reply With Quote
Old 01-02-2008, 12:39 PM   #8 (permalink)
Who
UnderModded
 
Join Date: Dec 2007
Location: San Jose
Posts: 319

Pablo - '07 Hyundai Santa Fe AWD
90 day: 23.62 mpg (US)
Thanks: 0
Thanked 2 Times in 2 Posts
It's too bad your Jeep wasn't a '96. The ScanGauge can be dialed in as a very accurate speedometer.
__________________
  Reply With Quote
Old 01-02-2008, 08:59 PM   #9 (permalink)
Giant Moving Eco-Wall
 
DifferentPointofView's Avatar
 
Join Date: Dec 2007
Location: The Dale, IL (or A-Dale)
Posts: 1,120

The Jeep! - '95 Jeep Grand Cherokee ZJ Laredo
90 day: 23.75 mpg (US)

The Caliber - '07 Dodge Caliber R/T
90 day: 30.6 mpg (US)

The 'Scort - '98 Ford Escort LX
Thanks: 0
Thanked 7 Times in 6 Posts
well, I used the GPS and it said it was only about 1mph off. I used cruise to rule out the driver and it was only 1mph off. not too bad
__________________


Yea.. I drive a Jeep and I'm on a fuel economy site, but you just wouldn't understand... "It's a Jeep thing!" *Jeep Wave*

Did I Use Too Many Abbreviations? Here's The Abbreviations List
  Reply With Quote
Old 02-14-2008, 04:02 AM   #10 (permalink)
DAN
EcoModding Lurker
 
Join Date: Jan 2008
Posts: 59
Thanks: 0
Thanked 1 Time in 1 Post
if the tire size is diff from stock you may be able to buy new grears to mach the diff. tires. i have done it a ford and a gm.

  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com