Speedometer Off

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Rutty
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Speedometer Off

Post by Rutty »

Hi all,

The speedometer in my 2000 has read off since I bought a couple of years ago. Just wondering if there is a fix and how involved it is. Currently it reads 70 mph (gauge) when actually going 60 mph (gps) and 35 mph (gauge) when actually going 30 mph (gps). I don't remember my 1600 being off this much.

Thanks,
Matt
'68 1600 (L20b)
'69 2000
Minnesota
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mraitch
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Re: Speedometer Off

Post by mraitch »

check the techwiki for info
Peter Harrison
1970 1600 (Stroker) - TOAD SAN (Eliza)
1970 1600 (Stock) - As Yet Unnamed
Lake Balboa (SFV) , California
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SLOroadster
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Re: Speedometer Off

Post by SLOroadster »

Wow, you are only off by 10 mph at 60? I'm off by 25 with the correct gear in the the transmission.

I've never found the speedo in these to be all that accurate unless the thing has been fully rebuilt. Some people have had better luck, some haven't

Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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jhayden
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Re: Speedometer Off

Post by jhayden »

Will is correct: the familiar medical expression “your results may vary” applies.

A sample of four SRL road tests of the period produced the following results:

(Indicated speed mph)/actual speed: (30)/27.5-30, (40)/37-39, (50)/45-48.5, (60)/54-57, (70)/63-69.2, (80)/72-76

(source: Datsun Roadsters 1962-1971, Brooklands Books)

Of course, important to bear in mind that these results were achieved using new equipment and standard tyres.

Jon
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nismou20
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Re: Speedometer Off

Post by nismou20 »

Tire size, rear end ratio, and speedo gear at trans come to mind. Someone mentioned earlier sometime back that there is a fella who makes a adapter to correct it. About $125.
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jhayden
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Re: Speedometer Off

Post by jhayden »

Yes, the results far exceeded my expectations, and it was a very cost effective investment:

viewtopic.php?f=39&t=33424&p=306672&hil ... or#p306672

Jon
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Rutty
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Re: Speedometer Off

Post by Rutty »

Looks like I'm not the only one with a speedo that's off. I might have to give billsspeedo.com a try.

Thanks,
Matt
'68 1600 (L20b)
'69 2000
Minnesota
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jhayden
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Re: Speedometer Off

Post by jhayden »

Matt,

Good luck – hope you are pleased with the results. Whether favorable or unfavorable, your comments regarding your experience will be helpful on this forum to those who may be on the fence about trying the product.

Jon
cromgnman
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Re: Speedometer Off

Post by cromgnman »

How do you tell which Pinion Gear Carrier is which?
Which carrier do I use with a purple (21 tooth gear)?
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