Menu toggle

Incorrect speedo reading

K

kenny baldwin

New member
Hi all.
It's been a while,full of busy work and car.its took 2.5years to fully rebuild the full running gear on the Carrera,and I am very happy with the end result,but not the bank manager, ha ha .had car out and the speedo seemed to be reading to slow so had friend follow me and yes it's out 15to20 miles an hour to slow so replaced speed sensor in the gearbox but still the reading is to slow,any ideals please let me know,cheers
 
Is the rolling radius of the tyres the same or have you increased the diameter as part of the rebuild?
 
Is that at all Speeds? seems a heck of a lot to be our 3-5 or so I'd understated but not 15-20 that is way out
Can you get hold of a sat nav and check at various speeds?
 
ORIGINAL: 944s2

Is that at all Speeds? seems a heck of a lot to be our 3-5 or so I'd understated but not 15-20 that is way out
Can you get hold of a sat nav and check at various speeds?
Click to expand...


Mines is normally between 3-5 miles out, the faster the higher the discrepancy.

15-20 is way to high, the speedo may need to be calibrated
 
IFAIK by law a speedo cannot read slower than actual speed. As a rule of thumb Porsches tend to read up to ten percent higher than actual. Most cars do.

I assume you checked it against a GPS readout. GPS is much more accurate but ideally you need to run for a few hundred yards at a constant speed to get a correct GPS reading.

If you want a good GPS utility and you have an Android phone try DigiHUD, there is a free version but for 99 pence you get some additional features.

Cheers,
 
You must log in or register to reply here.

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Porsche
Lockton
Pirelli
Officially approved
Oracle Finance
WEX Esso
Collecting Cars
Archant Dialogue
Back
Top