Hi Guys,

I pulled out my old MPH speedo today to replace it with a KPH one as I am too lazy to do the conversions in my head while I'm driving. The one I pulled out was a 90mph speedo and to replace it I have both a 140 and a 160 kph unit.

Is either of these a direct replacement to give an accurate speed? I have 195/60/R15 tyres all around so it will probably be out anyway but am wondering if one is going to be closer to accurate.

I just thought I'd seek some wisdom before I go for a drive with one (compared to GPS), replace it and go for another GPS drive to determine which is better...

I'm also thinking about one of those GPS speedos for simplicity (changing wheels etc.) but would prefer to stay stock for the time being.

The attached picture shows all three.

Thanks for the advice.

Are the speedos from same make and or model?

On Beetles type 3s type 2s Karmann Ghias etc they are all driven from the front LHS front wheel by cable...

so, it doesn't matter which speedo You have in the car, if the wheel tyre size was the same originally...
All Beetles and type 3s and Karmann ghias had 15 inch wheels with similar sized tyres [cross ply/fabric radial/steel radial] so the speedo will show the same speed...

so, You can fit a 140 or 160 KMH speedo and they will show the same speedo..

shame there wasn't some sort of adjustment for different sized tyres etc...

I have a 160KMH speedo with 165 x 15 tyres on 6 inch wide rims and speedo is about spot on...

LEE

Bajachris, the speedos I have are not from the exact same make and model (beggars can't be choosers!) but they are pretty close - within a year or 2.

Lee, thanks for the advice. So it sounds like the gearing for the different units is in the speedo itself and therefore doesn't matter which goes in! Great stuff! I think I also read a while ago that you did the LED conversion on your speedo. How do find that? I think the LEDs would be great for the oil/generator/indicator/high beams but are they too directional for the face of the speedo?

(Sorry, still can't get the photo to post...)

I tried drop in BA7S LEDs for speedo lighting and found the same thing too, just not dispersed enough to light it up well.
I ended up sticking one of those LED strips in there instead, make sure if you do that to get the SMD style so they dim properly with the rheostat.

I wouldnt worry about LEDs for oil and gen.
1 they are never on that much anyway and 2 the Gen light if you run an alternator uses the globe resistance to excite the alternator into charging and the LEDs just dont pull enough load to do that.
You can get around it with resistors and such but why bother for something that's rarely on?

Those 195/60s will make the speedo read abit fast, they are 4.65% smaller than stock 165s, so at 100km/h the speedo will read 104km/h if its still accurate after 4 decades.

Probably worth mentioning as well...another option is just to stick a KPH sticker over the top of the MPH dial. Most VW spares shops probably stock these (?). I've got one in my '66 & I barely even notice it's not original unless I stop to think about it.

I just do the math. Its cheaper. Just times 10mph X 1.6.

you can purchase a decal that stick on the glass cheap and easy

I initially used an online convertor to write the conversions of KMH to MPH for the common speeds (kmh): 50, 60, 70, 80, 100 and 110 in a table and taped it next to the speedo. Approximate conversions for each are about 30, 38, 43, 50, 60 and 65 mph. (plus or minus a couple for the people ready to correct me )

After a week you remember it off by heart, and the speeds you experience below or inbetween you can almost get a feel for it and guestimate

Plus its cool talking in mph old school nostalgia.