Following on from my previous topic on Propshaft Bearings http://www.vwsyncro.co.uk/data/forums/topic.asp?TOPIC_ID=3159&whichpage=2, it diversed into Speedo Drive Factors.
The last couple of posts are listed below;-
Chris wrote;-
quote:
The final drive ratio is different on the Country, as is the speedo calibration.My bet is that you have taken out an(original Golf Country) AXR code gearbox with a 68/14 = 4.85 to 1 diff (early type with 90mm drive flanges) & fitted an ARM code gearbox with a 67/15 = 4.46 diff, (later type with 100mm flanges)
btw the drive flange diameters are not related to the final drive ratios.
Also the 220 Kmph Country speedo has a drive factor of 1100 (
I think this is 1000 on my Chrom!– Clive – I was wrong []), the standard 220 Kmph LHD Syncro has a factor of 1080
While the UK RHD Speedo has a factor of 1740.to add to the confusion there are also 2 different speedo drive cogs which can be fitted to the gearbox end of the cable,
1 has 15 teeth while the other has 16.
and a coulple of posts later;-
quote:
The correct speedo head you need (p/n 193957033E) is available from herehttp://www.volkswagen-classic-parts.de/bestand/index_e.html
it is the only head with the correct rating (1740) & was only fitted to the RHD UK Syncro
the 2wd speedometer heads are rated at 1505 for the 1050/1300 cc & 1540 for the 1600/1800 motors
I believe that this figure relates to the number of turns the speedo cable must make to record 1 mile,
or 1 kilometer as in a kilometer speedo as the relevent figures are 935 & 950.
However, I had a look at wheel diameters and made the following observations;-
- Std Golf Syncro Tyre Size is 185/60R14 – 578mm Dia
- Std Golf Country Chrom Tyre Size 205/60R15 – 627mm Dia
Ratioing the tyre sizes = 578/627 = 0.92185
Multiplying the Drive Factor by this = 0.92185 * 1740 = 1604
Converting to km from mls = 1604 / 1.6 = 1002
Which is the Speedo Factor of my Golf Country (I’ll double check on the way home from work tonight)! No it’s not! Back to the drawing board.
Well, that mucked up all my calculations!
And I realised I should have been comparing the wheel sizes to the standard Country tyre size.
I shall now go away and do some more sums before I open my gob again[
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You could well be right! I just did a quick search of the internet.
The majority of the sites suggests the following as standard tyre sizes. Obviously they may have been other alternatives available!
- Vehicle – Tyre – Rolling Dia
- Lesser Golfs – 175/70R13 – 575
- GTi – 185/60R14 – 578
- Syncro – 185/60R14 – 578
- Edition 1 – 195/50R15 – 576
- Rallye – 205/50R15 – 586
- Country – 195/60R15 – 615
- Country Chrom – 205/60R15 – 627
Note that the majority of Golfs have the same rolling diameter, regardless of the wheel size.
Anyway, I digress. Back to my motor!
I decided to test the speedo last night on the way home so took the following readings;-
- 3450rpm – 120kph
- 2500rpm – 86kph
This compares with the values I got using the vwtechnic.com spreadsheet http://vwtechnic.com/transmission.htm using an ARM gearbox ratios;-
- 3450rpm – 121.8kph
- 2500rpm – 88.3kph
More to come as I have to get back to earning some money[
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