Pajero 4WD Club of Victoria Public Forum Pajero 4WD Club of Victoria Public Forum

Go Back   Pajero 4WD Club of Victoria Public Forum > Vehicles > Challenger/ Pajero Sport > PB -PC Challenger 2009 - 2014

PB -PC Challenger 2009 - 2014 Covering 2.5 HP diesel

Reply
 
Thread Tools Display Modes
  #1  
Old 22-11-18
fajer fajer is offline
Member
 
Join Date: Dec 2015
Location: Mooroopna North West
Posts: 167
Default Calculation of Speed and Kilometers

How accurate is the Challenger PC speedo?
A recent check compared to my GPS is
Challenger Speed 100kph GPS 93kph
Challenger Kilometers travelled 93.4kl GPS 92.1kl
Obviously two different methods are used to calculate the difference of speeds and kilometers travelled. So the question is which method is used to calculate the fuel economy and distance available?
Reply With Quote
  #2  
Old 22-11-18
old Jack's Avatar
old Jack old Jack is online now
Valued Member
 
Join Date: Jun 2011
Location: Adelaide
Posts: 6,297
Default

Kilometres traveled as displayed on the odometer.
Have you also checked your odometer against the km markers on the side of the road?

OJ.
__________________
2011 PB Base White Auto, Smartbar, Cooper STMaxx LT235/85R-16,TPMS, HR TB, 3 x Bushskinz, front +40mm Dobinson , rear +50mm EHDVR Lovells, Dobinson MT struts and shockers, Peddars 5899 cone springs, Windcheater rack, GME UHF, Custom alloy drawer system inc. 30lt Engel & 2 x 30 AH LiFePo batteries + elec controls, Tailgate hi-lift/long struts, Nightbreaker +130LB & Phillips +100 HB, Lightforce 20" single row driving beam LED lightbar, Scanguage II.
MM4x4 Auto Mate, Serial No 1 .
Reply With Quote
  #3  
Old 22-11-18
Dicko1's Avatar
Dicko1 Dicko1 is offline
Valued Member
 
Join Date: Dec 2014
Location: here
Posts: 4,991
Default

Quote:
Originally Posted by old Jack View Post
Kilometres traveled as displayed on the odometer.
Have you also checked your odometer against the km markers on the side of the road?

OJ.



I,ve checked my NW,s speedo with the road klm markers Over a 5 klm stretch I reckon I,m about .2 over So thats roughly 4klm per 100klms over what I have actually travelld. I just dont understand some of the ultra low fuel usage some members on the forum get. They must drive at 85kph, with no passengers or accessories and drive like "old women"....




Either that or their figures are just plain wrong.
__________________
Modified 2014 NW owner. ATUS..
Social media...the toilet bowl of the internet..
Reply With Quote
  #4  
Old 22-11-18
nj swb's Avatar
nj swb nj swb is offline
Resident
 
Join Date: Jun 2007
Location: Adelaide
Posts: 5,307
Default

Quote:
Originally Posted by fajer View Post
How accurate is the Challenger PC speedo?
A recent check compared to my GPS is
Challenger Speed 100kph GPS 93kph
Challenger Kilometers travelled 93.4kl GPS 92.1kl
Obviously two different methods are used to calculate the difference of speeds and kilometers travelled. So the question is which method is used to calculate the fuel economy and distance available?
Not different methods, just different factors.

The transfer case has a "sender" that puts out pulses based on rotation of the output shaft. Each pulse effectively represents a small distance - maybe a few hundred mm. An ecu counts the number of pulses and multiplies by a factor for distance (odometer). The same ecu measures the frequency the pulses and multiplies by a factor for speed (speedometer). Because our ADRs have some strange requirements for accuracy of the speedometer, different factors are used for each calculation.

Fuel economy and distance available don't use speed in the calculations - only distance. I find my economy reading is surprisingly accurate, if a little high - my calculations typically return slightly better economy than the meter. Distance wise, compared against a gps and roadside markers, my odometer is accurate within 0.5km per 100km. About 0.5% error.
__________________
NT Platinum. DiD Auto with 265/70R17 Toyo MT, Lift, Lockers, Lockup Mate, 3.15 gears, LRA Aux tank, bullbar, winch, lights, lots of touring stuff. Flappy paddles. MMCS is gone!

Project: NJ SWB. 285/75R16 ST Maxx, 2" OME suspension, 2" body lift, ARB 110, 120l tank, bullbar, scratches, no major dents. Fully engineered in SA. NW DiD & auto in place - a long way to go....
Reply With Quote
  #5  
Old 22-11-18
NJV6 NJV6 is offline
Valued Member
 
Join Date: Sep 2010
Location: New Zealand
Posts: 507
Default

Quote:
Originally Posted by nj swb View Post
my odometer is accurate within 0.5km per 100km. About 0.5% error.
That’s with your one size bigger tyres I take it? My NT says 100 on the dial, 97 on the ultragauge plugged into the ECU and 95 on the GPS!
__________________
1994 NJ SWB, 3.5 Manual, 285/75/16 KL71's, Twin ARB air lockers, XD9000 winch, custom bar.
1991 NH LWB, 3.9 V8, trayback, solid front axle, Toyota hi mount winch
2011 NT GLX DiD, 3.2 Manual, 265/65 BFG KO2's, SPV EGR, Lovells SD rear, HD front, Bilsteins, Custom underbody protection, Safari Snorkel, and loads of zip ties in the dash...
Reply With Quote
  #6  
Old 22-11-18
nj swb's Avatar
nj swb nj swb is offline
Resident
 
Join Date: Jun 2007
Location: Adelaide
Posts: 5,307
Default

Quote:
Originally Posted by NJV6 View Post
That’s with your one size bigger tyres I take it? My NT says 100 on the dial, 97 on the ultragauge plugged into the ECU and 95 on the GPS!
Yes, one size bigger tyres, but I'm talking distance, not speed. Multiple times, over a variety of distances in different places, I've compared what my odometer reports vs road side markers and OziExplorer trip meters. The difference typically works out at less than 500m error in 100km, but more than 400m. My odometer reports higher than the other methods. I think. With that level of error, it really doesn't bother me which way around it is.

Speed wise, its 2 - 3 km/h at 100km/h GPS i.e. 100km/h on the GPS is about 102 / 103 on the speedometer. I don't look at the "speedo" speed on Torque - I have it displaying GPS speed.

At times, I have 3 different GPS devices displaying speed - Torque, OziExplorer on an Android tablet, and OziExplorer on my Android in-dash head unit. It's not unusual for the readings to disagree by 1 or 2 km/h.
__________________
NT Platinum. DiD Auto with 265/70R17 Toyo MT, Lift, Lockers, Lockup Mate, 3.15 gears, LRA Aux tank, bullbar, winch, lights, lots of touring stuff. Flappy paddles. MMCS is gone!

Project: NJ SWB. 285/75R16 ST Maxx, 2" OME suspension, 2" body lift, ARB 110, 120l tank, bullbar, scratches, no major dents. Fully engineered in SA. NW DiD & auto in place - a long way to go....
Reply With Quote
  #7  
Old 22-11-18
BMN BMN is offline
Valued Member
 
Join Date: Jul 2010
Location: Perth WA
Posts: 547
Default

Quote:
Originally Posted by fajer View Post
How accurate is the Challenger PC speedo?
A recent check compared to my GPS is
Challenger Speed 100kph GPS 93kph
Challenger Kilometers travelled 93.4kl GPS 92.1kl
Obviously two different methods are used to calculate the difference of speeds and kilometers travelled. So the question is which method is used to calculate the fuel economy and distance available?
I think by law speedo is not allowed to read under and they have a 10% error allowance meaning speedo can show 100kph but actual speed is 90kph. I think this is one reason people appear to be sitting on 100kph in 110kph zones. My PB reads over like yours by about 7-8% so happily sit on 118-120kph speedo reading in 110 zones and never get flashed.
__________________
2010 PB LS Auto, 7seat, silver with lots of pinstripes, Dual batts, Toyo AT2, ARB roof rack, Rear storage/fridge, Bilstien/Kings
Reply With Quote
  #8  
Old 22-11-18
fajer fajer is offline
Member
 
Join Date: Dec 2015
Location: Mooroopna North West
Posts: 167
Default

Quote:
Originally Posted by old Jack View Post
Kilometres traveled as displayed on the odometer.
Have you also checked your odometer against the km markers on the side of the road?

OJ.
No I haven't. But an interesting suggestion. Not back home from overseas until mid Dec. Will give that a check. Interesting the comments from others
Reply With Quote
  #9  
Old 22-11-18
BMN BMN is offline
Valued Member
 
Join Date: Jul 2010
Location: Perth WA
Posts: 547
Default

Worse than what i thought. They are allowed 10% +4kph.....no wonder many drive under the speed limit
https://www.racq.com.au/cars-and-dri...peedo-accuracy
__________________
2010 PB LS Auto, 7seat, silver with lots of pinstripes, Dual batts, Toyo AT2, ARB roof rack, Rear storage/fridge, Bilstien/Kings
Reply With Quote
  #10  
Old 22-11-18
nj swb's Avatar
nj swb nj swb is offline
Resident
 
Join Date: Jun 2007
Location: Adelaide
Posts: 5,307
Default

Quote:
Originally Posted by BMN View Post
Worse than what i thought. They are allowed 10% +4kph.....no wonder many drive under the speed limit
Yep. Safety first! Don't drive at the speed limit, drive under it. So people think they're "driving safely" at 95km/h, when they're really somewhere under 90, and glaring disapprovingly at everybody driving 10km/h faster - but still under the speed limit.

Ignorance may be bliss, but so many of the ignorant are still unhappy with their fellow road users.
__________________
NT Platinum. DiD Auto with 265/70R17 Toyo MT, Lift, Lockers, Lockup Mate, 3.15 gears, LRA Aux tank, bullbar, winch, lights, lots of touring stuff. Flappy paddles. MMCS is gone!

Project: NJ SWB. 285/75R16 ST Maxx, 2" OME suspension, 2" body lift, ARB 110, 120l tank, bullbar, scratches, no major dents. Fully engineered in SA. NW DiD & auto in place - a long way to go....
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Axle Weight Calculation Spreadsheet NTBenny General Info 18 29-10-18 08:43 PM
Low speed noise/ High Speed Wobble NL Pajero datbitz Generation 2 Pajero 6 23-11-15 10:56 AM
Fan Speed Controler to lower AC pedastal fan speed? Bru9 Bits and Pieces 7 15-11-15 07:37 PM
How many city kilometers/hours does 100 000km country miles equal? Keeno Mechanical 10 23-05-13 12:22 AM
Kilometers before towing NIFTY NEV Generation 4-1 Pajero 6 27-07-08 06:44 PM


All times are GMT +10. The time now is 11:36 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.