User Tag List

Page 1 of 4 123 ... LastLast
Results 1 to 20 of 66

Thread: Speedo is about 10% over

  1. Default Speedo is about 10% over

    Just bought an MPS, my speedo reads about 10% over the actual speed it is going (says 66km = actually going 60km etc.) This is according to my GPS, one of those road-side speedo checker things and also just the speed of the other traffic on the road.

    How can this be fixed?

    Thanks.
    Pete

  2. #2

    Default

    you have aftermarket wheels on right?

    you need OEM spec diameter tyres to correct any diameter discrepancy.

  3. #3

    Default

    Some (I was under the impression all new) speedos are calibrated to show a greater speed than you're actually doing (and this can be a good thing).
    It's actually a part of one of the Australian vehicle design laws the car manufacturer has to comply with.

    Anyway, the only thing i've ever seen used to correct this is,... Bring on MCM!



  4. #4
    Join Date
    Apr 2012
    Location
    South Perth, Western Australia
    Posts
    400

    Default

    Mine has always been out when reading from the dash cluster (with stock wheels and tyres), however interesting to note that the reading from the ECU via UltraGauge/AccessPort was correct as per my GPS.

  5. #5

    Default

    Better 10% over then under%... means when you are on autopilot less chance of camera action.

    Mine is about 4-5% over with the RX8 rims and tyres as they are slightly smaller then stock. (This is GPS speed)

  6. #6

    Default

    Quote Originally Posted by GibbA View Post
    Some (I was under the impression all new) speedos are calibrated to show a greater speed than you're actually doing (and this can be a good thing).
    It's actually a part of one of the Australian vehicle design laws the car manufacturer has to comply with.
    Correct. The Australian standard for new cars states that the speedo must over estimate the speed at which the car is travelling. 10% is high, but pretty common in all new cars.

  7. #7

    Default

    Heaps of cars are out ,I have a Subaru forester with stock wheels and the speedo is out by 9km/hr doesn't need to have aftermarket wheels to be out

  8. Default

    Ok, thanks very much guys.

    I believe I've got the stock rims/tyres (powder coated black). They are Mazda rims, can't think of someone getting new rims and getting different Mazda ones.

    Might just have to get over it then! Quite annoying though. Ah well.

  9. #9

    Default

    My car was about the same
    My speedo would read higher that my actual

    Using an Ultragauge or my Cobb AP the speed was dead on and matched my GPS

    Now that I changed wheels and gone to 19" my speedo is a little more accurate but reads higher than actual but my Cobb AP is reading lower than actual

    Any advice on how to get this re calibrated in Melbourne?

  10. #10
    Join Date
    Aug 2011
    Location
    Sydney North
    Posts
    441

    Default

    So if the speed limit is 110 I can set cruise control at 121 and display display

  11. #11

    Default

    Speedos are supposed to have no greater error than 3%.

  12. #12
    Join Date
    Aug 2009
    Location
    hunter valley
    Posts
    6,403

    Default

    easy fix. Take you dash out and move your needle up 5-8ks will start at 5kph rather than 0 but if you can live with that.......

  13. #13

    Default

    Quote Originally Posted by Doug_MPS6 View Post
    Speedos are supposed to have no greater error than 3%.
    I think you will find that's it's more like 10%when I questioned Subaru they told me most are out by 9% which is still ok by ADR
    as long as it's not the other way ie speedo reading 100 but actual speed is more
    Last edited by chef; 23-10-2013 at 04:16 PM.
    //BNR3//HDI FMIC//HTP 3" intake//
    // Ecutek tune//CPE DP/ HPFP//
    // Tein performance street Coilovers //
    // Whiteline RSB// 240kwATW bum Dyno //

  14. #14
    Join Date
    Apr 2012
    Location
    South Perth, Western Australia
    Posts
    400

    Default

    Quote Originally Posted by RedDjinn View Post
    easy fix. Take you dash out and move your needle up 5-8ks will start at 5kph rather than 0 but if you can live with that.......
    This won't work. It's out by a percentage figure, not a standard variance throughout the whole speed range.
    BK MPS3 Sports - Work Meister S1R
    CP-e Catalogue. JDM Goodies.

  15. #15

    Default

    Quote Originally Posted by bodyboardingbum View Post
    This won't work. It's out by a percentage figure, not a standard variance throughout the whole speed range.
    This exactly ^^ it's out by a function of your speed.

    Plus, I wouldn't want to go fiddling with the needles of your dials, they are rather fragile.. :/
    --> 2008 Metro Grey Sports Pack Gen1 <--

    CS SRI ll CS TIP ll CS AB ll 2XS SSP ll 2XS FMIC ll SURE Anchors ll Enkei RPF1's 17x9 +45 ll Lamin-X Fog Tint ll DBA T3 4000 series ll Remsa pads ll Braided lines
    CP-E S2 RMM ll Hankook RS3 235/40/17 ll Forge V1 BPV ll Whiteline RSB ll AutoTech HPFP
    ll Spin-on Conversion ll Rear Diffuser
    DGR Coilovers ll LED Replacement lights ll "08-MPS" plates ll Cobb AP V3 (E85) ll CP-e TBE ll OCC






  16. #16

    Default

    I'm guessing if I get my speedo calibrated, my Cobb will still be out?

  17. #17

    Default

    i'll be taking apart my Dash soonish to replace my AC evaporator so when i get the dash cluster out i'll see if there is any easy way to adjust it

  18. Default

    Quote Originally Posted by rayd View Post
    i'll be taking apart my Dash soonish to replace my AC evaporator so when i get the dash cluster out i'll see if there is any easy way to adjust it
    you can purchase speedo re-calibration units that are adjustable and can be added.
    there are also companies who do this... as to make it legal they have to be certified companies, using certified units and certified calibrated GPS speed readers.

    We had this done to one of our 300zx's as we needed larger wheels to fit brakes under, and for some better suspension geometry, but we still wanted to maintain a 45 series profile tyre.
    Its 90% a track car... but we still wanted it to be legal when street driven, so made sure everything was engineered.

    but none the less... you can always just buy these units and calibrate yourself. If you aren't running a different rolling diameter than stock... then mr Police man will have no reason to suspect a re-calibrated speedo.

  19. Default

    As everyone stated, majority of cars with analog speedometer will display uncalibrated speed. Have a look at 2008ish ford falcon user manual, it shows actual speed of 97 when driving at 100..

    Sent from my GT-I9100 using Tapatalk 4

  20. Default

    Quote Originally Posted by AzzA SP20 View Post
    you can purchase speedo re-calibration units that are adjustable and can be added.
    there are also companies who do this... as to make it legal they have to be certified companies, using certified units and certified calibrated GPS speed readers.

    We had this done to one of our 300zx's as we needed larger wheels to fit brakes under, and for some better suspension geometry, but we still wanted to maintain a 45 series profile tyre.
    Its 90% a track car... but we still wanted it to be legal when street driven, so made sure everything was engineered.

    but none the less... you can always just buy these units and calibrate yourself. If you aren't running a different rolling diameter than stock... then mr Police man will have no reason to suspect a re-calibrated speedo.
    +1 to whatever he said..

    Similar Calibration units are used by police for calibrating high performance vehicles however they do cost a fortune..

    I wouldn't even worry about it. As I said earlier, it's the analog speedometer. If you check the data logs through Cobb, you will see the correct speed..

    Sent from my GT-I9100 using Tapatalk 4



Page 1 of 4 123 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •