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> Imperial to Metric Speedometer conversion
*kennyd*914
post Sep 13 2005, 09:16 PM
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I'm looking for some assistance; I have recently joined the club and also picked up a 1974 1.8L (my last one was a '73 1.7L in 1985). As I'm in Canada, I picked up a metric speedometer but I don't believe that the conversion is as easy as a change over to a new speedometer. I believe that I require some adjusting as the speed doesn't match the readings. Is this a difficult procedure?

Any advise would be great. thanks.
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MecGen
post Sep 13 2005, 09:23 PM
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Hey Man

First off welcome to the Board (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)
Us Canucks are catching up (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

Can't realy help on the conversion but the first question everbody is going to ask is "what size tires" and is your speed too high or low? (IMG:http://www.914world.com/bbs2/html/emoticons/clap.gif)

There are a couple members here that realy know Speedoheads, matbe they will chime ine

Good Luck
Later
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GWN7
post Sep 13 2005, 10:14 PM
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Hello and Welcome (IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif)

The easist way to check is to use (buy or borrow) a GPS.

After 30+ years your speedo can be off due to mechanical failure along with a difference in tire size.
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Mark Henry
post Sep 14 2005, 07:08 AM
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Welcome! (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)

It's just a simple swap...but as said tire size will change things.
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spare time toys
post Sep 14 2005, 07:18 AM
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I think the dif. is the face of the speedo not the internals. I know for GM the guts were the same. Like the others said tire size will throw it off.
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Mark Henry
post Sep 14 2005, 07:51 AM
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The 165/15 tires that came with the car had a AR of about 80...so if you put on 205/50 15's it will throw off the speedo around 10mph (slower than the speedo says) so that will seem a lot in KPH.
If you run 195/65 15's it won't be as bad.
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SirAndy
post Sep 14 2005, 12:41 PM
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QUOTE (Mark Henry @ Sep 14 2005, 06:08 AM)
It's just a simple swap...but as said tire size will change things.

(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif) simple swap, but the tire size is important. just use the tire calculator in our "914 Info" section to find out how much your speedo is off ...

(IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) Andy
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DonTraver
post Sep 14 2005, 01:45 PM
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When I put the 205/50/15's on, my speedo was off too. Took the car to a local speedo shop, they calibrated the speedo on this machine that looks like a dyno and they counted the rotations that the speedo cable turned, then regeared the speedo, also repainted the pointers. It reads right on on speed, total milage is right on, and the trip odometer reads 104 miles for each 100 miles driven. Cost about $120., took about 2 hours. Well worth it, and interesting to watch.

Good luck, Don
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Downunderman
post Sep 14 2005, 04:32 PM
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I have been thinking about a GPS speedo for a while now but I can't find a metric one. Can then get rid of the cable, angle drive etc. Only problem is they dont work well in tunnels (or at all)

http://www.gaffrigperformance.com/Products...eSubCategory=42
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*kennyd*914
post Sep 14 2005, 08:52 PM
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I'm not overly happy with the metric speedometer needle as it currently looks. It isn't exactly the same as the origional. The metric replacement has a silver cap in the center. Is there a silver capped RPM guage and fuel guage as well on the Euro guages?

Let me know,

ken
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Mark Henry
post Sep 15 2005, 04:56 AM
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QUOTE (*kennyd*914 @ Sep 14 2005, 10:52 PM)
The metric replacement has a silver cap in the center. Is there a silver capped RPM guage and fuel guage as well on the Euro guages?

Let me know,

ken

Early gauges had the silver button...late did not.
-'73 had them and '74- didn't (I think)
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redshift
post Sep 15 2005, 04:59 AM
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You need a metric tire.



M
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*kennyd*914
post Sep 15 2005, 05:57 AM
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I do have a metric tire, however, it resides below my rib cage.!!
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