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TR7 speedo

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Henry
Wedgling
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Joined: 26 May 2015 12:15
Location: Nr Pershore, Worcs

TR7 speedo

Postby Henry » 14 Aug 2015 14:21

I guess I could ask Steve this but the answer may be of interest to others.
My car (Y reg) has a speedo with 130 mph as the last written digit, the 140 mph mark is a rectangle. While at Malvern I picked up a speedo that has 140 mph as the last written digit, my question is are the two geared differently or is this all done at the gearbox?
I believe the 140 mph one is from an early car, so may have been calibrated for 4 speed 'box.
Thanks in anticipation.
My Triumphs:
TR7 V8 KDM995Y Current
GT6 PUD612M still in family
TR7 V8 PLK224W Sold
TR7 donor car for PLK224W
GT6 written off
2.5 PI saloon - sold

TR Tony
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Re: TR7 speedo

Postby TR Tony » 17 Aug 2015 14:22

Not aware of any differences in the speedo itself Henry, there were several different "faces" over the years, MPH, KPH, even a USA version that only read up to 85MPH! They are all calibrated the same.

All the gearing of the speedo is done by a combination of an output shaft gear and a pinion gear at the output from the gearbox. There are various gears, identified by colour, which were used to achieve the correct speed reading on the speedo itself, according to the final drive ratio in the car.
Tony
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1981 TR7 FHC Cavalry Blue
1980 TR7V8 DHC Jaguar Regency Red - sadly sold!
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FI Spyder
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Re: TR7 speedo

Postby FI Spyder » 17 Aug 2015 15:45

This brought up an interesting question (to me any way). The US speedos have the large outside numbers in mph and small numbers on the inner circle in kph for when they are driving in Canada and Canadian speedos have large outside numbers in kph and small numbers in the inner circle in mph for when they are driving in the US. The question is are the UK/Europe speedos only in kph?
- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 2013 Volt - Yellow TCT

saabfast
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Re: TR7 speedo

Postby saabfast » 17 Aug 2015 20:16

European ones are probably in kph, maybe with little MPH numbers as you describe Canadian ones. UK ones are in MPH as the large size with little kph numbers.
Alan
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Henry
Wedgling
Posts: 48
Joined: 26 May 2015 12:15
Location: Nr Pershore, Worcs

Re: TR7 speedo

Postby Henry » 25 Aug 2015 12:37

Thanks for the reply's all, apologies for the late reply - been away on hol's for 10 days :D
I guessed that the speedo's would be the same, just wanted to check, I'm familiar with the gearing variations as I have played about with Land Rovers :shock:
There was a brand new KPH speedo head for sale at the TR Register do at Malvern recently so they do indeed exist.
My Triumphs:
TR7 V8 KDM995Y Current
GT6 PUD612M still in family
TR7 V8 PLK224W Sold
TR7 donor car for PLK224W
GT6 written off
2.5 PI saloon - sold

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