Speedometers

[grogee]

Back in the day I used to get pissed off with my classmates who insisted their Dad's Marina would do 140mph because that was was the highest reading on the speedo. 

Later in life I spent some time in the US of Stateside, where the opposite was true - their (usually domestic car) speedos would rarely read past 100mph, possibly to discourage American people attempting to drive at mind-bendingly moderate speeds.

It got me wondering, what was the purpose of Ford (for example) fitting their Cortina with a 140mph speedo? There weren't any models in the range that could come remotely close to that figure. 

Do we think it was a marketing thing?

[horriblemercedes]

For several years, speedometers in America could read 85mph max. This was at the same time as the national speed limit was reduced to 55.

 

The idea was to slow people down to save fuel, but in practice it did nothing so the speedometer rule was abandoned in 1982 and the 55mph limit in 1995

[Lacquer Peel]

[Dyslexic Viking]

This reminds me. This is the speedometer on a Norwegian sold so kmh diesel Bedford from the 1960s. And the speedometer goes to 140 kmh (86 mph) this will not go 140 even if you drove it off a cliff so why does it have this?  So I'm wondering the same thing.

[adw1977]

Wasn't the Cortina speedo also used on the Granada?  Some Granadas had a quoted top speed of at least 120.

[Sham]

2 minutes ago, adw1977 said:

Wasn't the Cortina speedo also used on the Granada?  Some Granadas had a quoted top speed of at least 120.

I was going to say that parts were often shared between models in the range, and sometimes between manufacturers too. Even if they looked different, the innards were often the same and so was the gearbox or electronic drive.

The US situation was a government mandate.

[Zelandeth]

I'd honestly prefer the 85mph US style speedometer to the absolute nonsense we've got here nowadays.  See also the Golf we had a couple of years ago where the speedometer went to 200mph.  Bloody stupid.  Meant the usable range was about a quarter of the thing and the needle was about 30mph wide.

Saab had a decent solution I thought on the 9-5 where the scale above 100 was heavily condensed, allowing the bit you're actually going to read to be larger and clearer.

[Missy Charm]

Let's say that the Cortina dates from 1978 (I don't know, but let's not be too pedantic).  In 1978 Ford's were also making the 3.0 Capri, which had a claimed top speed of 123 mph; it was probably their fastest production car at that point.  A 140 mph speedometer would be ideal for the Capri as it covers the full theoretical speed range and has a little bit left over.  

The 2.3 Cortina of the same year could do 108 mph.  Adding a similar 20 mph margin of grace gives 128 mph, or near as damnit 130 mph.  That leads to the question of whether it would be worth specially manufacturing and calibrating a 130 mph clock, which would have a different scale, when the 140 mph clock from the Capri is sitting in the stockroom.  The answer is 'no'.  

[CreepingJesus]

The question was always how optimistic the speedo was. Maybe Ford went as far as 140mph to give themselves a margin of error. Maybe a tighter scale made the instrument itself better somehow?

The other possibility is largely aesthetic: the arc of numbers fitted in more harmoniously with the other instruments. Bit pointless on a base Fiesta, but higher end models would have more gauges, so maybe it fitted better with a tachometer and so on?

[mat_the_cat]

This is an annoyance with the LT.

What use is a 120mph speedo when it'll only do just over half that? 70mph is the geared maximum, so I'd much rather use more of the scale for readability. Is this shared with other VW models does anyone know?

[stuboy]

150 mph same as my mondeo has..... i wont be trying to see if it would try.........

170 mph is what a st220 have. does it encourage people to speed............

[rob88h]

Is it so that useful speeds are in sensible places like 70mph at the top/12 o’clock? Massive guess but I know race cars do this with tachos and temp gauges and stuff; so the ideals are all 12 o’clock to make glancing them easy. 

[RoverFolkUs]

I've never thought it to be anything more than a bit of psychology to make people think they've got a lot more for their money. 

A car that "only goes upto 70" doesn't sound as thrilling as one that "goes upto 150"

Come to think of it, is that where the phrase "strong powerful engine" comes from in car adverts? Almost always used in irony, such as describing a 0.8L Daewoo Matiz 🙄

 

[garbaldy]

Most car companies do it.   Flat out with 1256 power and a quarter left for good measure.

The Japanese are not as bad as managed a 114mph on GPS with Speedo nudging Max even though I'm sure it's rated at 104mph or so.

[Zelandeth]

25 minutes ago, mat_the_cat said:

This is an annoyance with the LT.

What use is a 120mph speedo when it'll only do just over half that? 70mph is the geared maximum, so I'd much rather use more of the scale for readability. Is this shared with other VW models does anyone know?

Interesting.  The one in my T25 went up to a round 100 - though it realistically would probably have managed 60-ish downhill with a following wind.

The one in my Merc seems pretty sensible with 90mph being full scale.  80-ish is doable if the wind is in the right direction.

As you say, it makes it far easier to read at a glance because you're basically able to use the full sweep more or less.

[MorrisItalSLX]

Toyota Australia decided to mark the unusable area of my Corolla’s speedometer in orange (fastest I’ve got it to was 120kph, downhill on a 110kph motorway with foot flat to the floor).

Then, when EFI was standardised across the Corolla range Toyota decided that 180kph wasn’t enough for all the extra power and fitted 200kph speedometers!

They still had the orange band starting at 100, despite the Australian motorway/freeway speed limit being 110kph.

[St.Jude]

The speedo on my Peugeot 107 goes to a bit over 110mph (think 114mph).

I got there, once, on the Autobahn in Germany 10 years ago, slightly downhill.

The Corolla, I think, went to 140mph but would only get to 125mph on the Autobahn in Germany 3 years ago (nearly), slightly downhill.

[AnnoyingPentium]

The Fab says 120 on the speedo, but honestly it won't see much over [redacted] mph. It's nice that 60mph is dead centre at the top of the speedometer though.

[warren t claim]

4 hours ago, garbaldy said:

Most car companies do it.   Flat out with 1256 power and a quarter left for good measure.

The Japanese are not as bad as managed a 114mph on GPS with Speedo nudging Max even though I'm sure it's rated at 104mph or so.

I thought the 100mph Viva speedo was only fitted to the 1159cc model? The 1256 had the 120mph speedo?

[warren t claim]

Let's have a blast from the past.

 

 

[PhilA]

Went look see as the fleet has changed. Portion of each speedometer technically unusable according to top speed figures marked in red, versus the maximum legal speed anywhere in this state*, above which is marked yellow.

 

Q60. Vmax 163, scale 180.

 

Ram 1500, Vmax 105, scale 120.

 

Chieftain, Vmax 83, scale 100.

 

GTA, Vmax 96, scale 100.

 

Plymouth, Vmax 122, scale 120.

The Infiniti is the only one that really is a bit silly in terms of useable scale. You can always put the digital readout on the screen too.

 

Phil

 

*Other states differ, for instance the interstate in portions of Texas is 75, parts of Montana still have no limit. New York has a state highway maximum of 55.

[Asimo]

Don’t understand the question.

[garbaldy]

5 hours ago, warren t claim said:

I thought the 100mph Viva speedo was only fitted to the 1159cc model? The 1256 had the 120mph speedo?

Not sure but this one is registered as 1256cc unless it's had engine upgrade or different clocks in its 50  years or so service,.  It does have drum brakes all round 🤔

[Rocket88]

15 hours ago, horriblemercedes said:

For several years, speedometers in America could read 85mph max. This was at the same time as the national speed limit was reduced to 55.

 

The idea was to slow people down to save fuel, but in practice it did nothing so the speedometer rule was abandoned in 1982 and the 55mph limit in 1995

I had a Chrysler Codoba with an 85 mph speedo, that made a horrendous chiming noise when you got anywhere near 85. I was hooning down the M5, the thing started it’s boinging, keep my foot in, and it made a noise like an exploding cuckoo clock…. Never uttered a sound after that….

[chaseracer]

Good work 😎

[grogee]

19 hours ago, Missy Charm said:

Let's say that the Cortina dates from 1978 (I don't know, but let's not be too pedantic).  In 1978 Ford's were also making the 3.0 Capri, which had a claimed top speed of 123 mph; it was probably their fastest production car at that point.  A 140 mph speedometer would be ideal for the Capri as it covers the full theoretical speed range and has a little bit left over.  

The 2.3 Cortina of the same year could do 108 mph.  Adding a similar 20 mph margin of grace gives 128 mph, or near as damnit 130 mph.  That leads to the question of whether it would be worth specially manufacturing and calibrating a 130 mph clock, which would have a different scale, when the 140 mph clock from the Capri is sitting in the stockroom.  The answer is 'no'.  

I'm not sure the Capri used the same speedo as Cortina, I thought Capri had separate clocks unlike the integrated panel in Cortina. Someone will be along shortly to correct me I'm sure. 

Your point still stands though, if the mechanical speedo cable and clutch gubbins were common to both, such that speed x = angle A on both cars. 

I think ultimately I felt short-changed that my Dad's 1982 1.6L estate Cortina never did 140mph. 

[Aston Martin]

On the new M5 CS the speedo goes to 200mph, but it's digital and so you'd spend your life only using the bottom cm to get to 40 anyway.

Surely with digital, you could make a "upto 70 mode" or a "look at my massive cock 200 mode"

[PhilA]

Oh but ze autobahn.

 

Because the Autobahn exists, you get to have Massive Cock Mode all the time.

It would make sense to have it selectable. Say, regular driving it just goes to 100; select sport and it goes to 200.

 

Didn't SAAB have it so the scale changed once you got to 100, and each graduation became 20 or 25 instead of 10?

[2flags]

The latest Seat has different setting for the dash. I know on one all you get is a simple digital speedo. On the others it can light up like a fighter jet! I remember as a lad looking at the speedos of things like A60's and Vauxhall Victors. They had 100mph speedo's. Only if you drove them off Beachy Head would they do that. 85mph max and that was optimistic. 

[LightBulbFun]

if we are on about optimistic speedos, I think I can win this cake!

who wants to guess what the actual top speed of the vehicle this speedometer is attached to!  

about 12Mph! thats right about 12Mph is the top speed of the machine its installed in from what I can find in my research! 

can anyone else find anything as "over speedo-ed" as this? about 90% of it is going unused here LOL

 

 

on the opposite end of the scale (hah) the often quoted (but no one knows where it originated from) top speed of my model of car is 82Mph, but the speedometer of my car only goes up to 80Mph, so when I was researching this matter, I  was left wondering where did 82 come from!

until I remembered older revisions of my model of car have a speedo that technically clocks up to 86 if you count the Minor markings past the 80 Major!

so someone could get to 82Mph and see that they are doing that speed!