Here's why your car's speedometer goes to 160 mph even though that will never happen

When I owned a 1989 Ford Thunderbird Super Coupe, its dial only showed up to 120 MPH, so I can’t say how fast I was actually going that one time I really opened it up on the Interstate. Burying the needle gives just a rough notion.

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Almost never. If you have a pressing need to know your speed, it’s usually a matter of doing the math beforehand to know X RPM in Y gear = speed.

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but I can’t drive 55!

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OK, I’m dumb—why is there a red tick at 30 mph :confused:

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It does have an incredibly cool font to compensate for the slowness.

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Having previously heard this fact about the DeLorean I hadn’t even thought to question why the speedo only went to 85, but thanks to the OP I’ve learned a thing. Fun!

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The speedometer in question:

The Office Pam GIF

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a common speed limit?

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sure, if we could get Americans to go for it. it’d be a hard sell. but you’re right, it needs to be a cultural change, so it’ll be slow if it happens at all. the culture now is “you’re 16, you get to drive now.” but not only is driver education not mandatory, I don’t think it’s even an option at public schools anymore. they used to teach it but I heard it was phased out.
I let my license lapse and had to take both the “writen” (computer) and the driving test again last year. it wasn’t that it was intentionally easy, but time constraints dictated that it was a multiple choice test (i e. multiple guess), and my driving proctor was so overworked she had to cram like 4 tests into an hour (even though we all registered months in advance, they still managed to overbook her). my biggest critique was the study material was about rules and signs, but not so much about how to determine right of way, although it was obliquely addressed with questions about specific scenarios. and the driving test was fairly thorough but there was no highway or interstate driving and like I said pretty short. but there’s a lot of scuttlebutt about test locations that only make you drive around the block, allegedly common in some places.

@newbrain … yeah, pretty much. I considered making an analogy but I didn’t want to “Godwin” my post.

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My car tops at 140, putting 70mph straight up. Which always made sense like the left half is speeds it’s reasonable to go, the right half are speeds it’s not reasonable to go.

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Oh, I kind of like how that looks, actually. Good design!

It is a hearse, after all!

sick way GIF

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As an indicator, a line changing angle from 45* below center to 45* above center is extremely effective interface design. High precision, instant comprehension. Down is less, up is more. Always means the same thing. Precision. You don’t need the numbers, you just anchor it and notice it bend up and down, pull it back to the correct slope.

All the ‘updates’ tried over the years – horizontal progress bar, numbers only – have been less good because it’s the human brain we’re building for, not the car.

Digital numbers appear to be the future of HUDs, but it’s a damn shame.

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Volvo used to put a tick at 55, then a universal top speed on Interstates.

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My son did his driving test and I was waiting for him and was stunned when he was back 15 minutes later. I though he had failed. Turns out they went up the road, two lanes each way with center divide, came off at the first Interchange, came back the other way to an Interchange, back on the road and take a right to return to the driving school. Oh and before they drove anywhere he had to parallel park in a special spot. Fail that and you fail the test. I was not impressed.
Car wise there are probably more SUV and pickups in the US that might affect the death rates too when compared to Europe.

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My car does that. It reads the GPS and the speed signs on the road side and warns me if I’m going too fast. It even helpfully suggests it could set the speed limiter function to the slower speed.for me.

MY old car, a 3-litre Jaguar actually could do over 150mph according to spec but I never went fast than maybe 90.

I agree with the point that a sweep hand gives you a sense of acceleration which a digital readout doesn’t, but actually once you get used to your car you’ll get that sense, and a sense of correct speed, from ambient conditions such as the road and engine noise.

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i think the suv issue is probably the thing.

( i also wonder if traffic density and time of day might figure in. id imagine more people in the us have commutes of significant distances at times when they are overworked or underslept. germany probably has more public transit and fewer people working multiple jobs )

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oi’mARRRRGH

It’s not just American cars. It’s all cars, in general. (But not racing cars, you dolts!) Back forty years ago when I did a car maintenance course they told us that your peak performance (and best mileage) was when your car’s speedometer was pointing straight up - at what would be twelve o’clock on a clock. It’s a useful piece of information that I never forgot. Unlike the rest of the course.

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…even though that will never happen

Well, not with that attitude…

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There’s no way that’s true. They told you an old wives’ tale. On most cars I’ve owned, straight up is 80mph, which is much too high for peak fuel economy. Fuel economy at high speed is governed entirely by aerodynamics (because the transmission is in a high gear and you’re not accelerating). Aerodynamic drag goes up exponentially with speed. Peak highway cruising efficiency drops dramatically every few mph above 60.

I raced cars for 15 years and most of them had speedos. It’s a useful driver data point for split times and corner entry speed (which determines braking point), despite what many armchair experts in this thread think.

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