That used to be a reasonable explanation, but there are a great many cars out there now that do not have a manual-transmission option. My wife’s Honda CRV is an example.
What makes you think Honda designed an instrument binnacle specifically for the CR-V? Also, what year was the CR-V? I can almost guarantee there was a manual option, even if it wasn’t offered by her dealer.
I’ve driven many a car with a standard transmission and have never had one with a tach. I could hear and feel when it’s time to shift gears. After you’ve had a particular car for awhile, the process becomes automatic (heh) and you don’t even have to think about it.
Me too… and perplexingly enough, my previous pickup had a stick and no tach.
I think it’s more a matter of having uniform manufacturing than anything else. It’s probably easier to just make one dash instrument cluster, and put it on everything, than to worry if the car is a stick or auto at the point when they’re putting the dash in.
On automatics, I’d prefer to have an oil temp gauge, a oil pressure gauge, a voltmeter and an ammeter instead of a tachometer, but that’s a lot more gauges than most people care about, and certainly more than most manufacturers are going to put on their dashes.
The CR-V has been automatic-only in the US for a while now, but it’s still sold overseas with a stick. However, I’ll give the F-150 as an example of a car only sold as an auto that comes with a tach standard. I’m sure there’s other ones out there.
However, you are technically correct that the reason why cars come with tachs is because they only use one cluster, but not for the reason you’re thinking. As has been repeatedly pointed out, there’s no reason why a manual needs a tach any more than an automatic for most drivers*. The real reason is that for various reasons optional features in general have been going away. It’s cheaper for the car makers to just give everyone a tach than put in, say, a huge ugly gas gauge or a big empty spot in the dash like they used to give the cheapskates. Read more about it here: Avoidable Contact: Airbags Killed the AM Radio Star. | The Truth About Cars
*I’d argue automatics need tachs MORE than manuals. On a manual, the tach doesn’t tell you anything you couldn’t infer from your speed and what gear you’re in. The hashmarks on the speedo many older cars had work just as well. On an automatic (especially a quiet one) you might need the tach to figure out how hard the engine is working.
:smack:
You’re right; it’s just that the manual version isn’t available in the US.
This might be true now, but it ignores any historical context. Tachometers used to be additional options. Consider the lowly Civic, which just happens to be the car I’m most familiar with. In the 80s and 90s, tachometers weren’t available on the base models. Notice it’s totally not there on this 88-89 Civic DX cluster. The Civic Si, on the other hand, had a tachometer. You’ll also notice that Honda changed the cluster between 88-89 and 90-91, during their “mid-model refresh.” And the changes were mostly pointless. On top of that, the Si-R models that were available overseas had a different tachometer (8200 rpm redline instead of 6500) and/or were in kms instead of miles, although the tach/speedo/mileage counter are all pieces that pop in and out of the base cluster.
Now, the rub is that Honda made a completely different set of gauges for automatics. I know that picture is small, but that’s an 88-89 Civic DX cluster for an automatic, and you can see the PRNDL indicator on the left in between the temp and fuel gauges. At the time, I believe there was only one Civic (the EX model) that had both an automatic and a tach, and I can’t find any pictures of it, but the point is that in America, the 88-91 Honda Civic had 8 possible gauge clusters depending on trim level, transmission, and model year. Globally there must have been dozens. This isn’t a part that Honda just made a million of, all identical, and slapped it into every car.
That pattern persisted all through the 90s until I stopped paying attention.
The tachometer was only available on sport or higher level trim options, regardless of the transmission. So why does this automatic 91 Accord clusterYrw~~60_35.JPG) have a tachometer, if the Accord is neither sporty or expensive, and if Honda made a non-tach cluster for Accords at the time (which they did)? Because the potential buyer at the time knew that no-tach = cheapass car.
Eventually, tachometers got so cheap that it just made sense to include them on everything and not risk turning off buyers who still, even subconsciously, rembembered the days when a tachometer was a option.
Unless you have perfect pitch, the visual presentation is better calibrated.
I’ve driven a manual-transmission pickup that had no tachometer. It wasn’t a problem, except when really trying to accelerate quickly - I didn’t know where the redline was. Sure, I could hear the engine spinning up, but how high in pitch could I go before I had to shift? I didn’t know.
I could probably have looked in the owner’s manual for a redline, done some simple math to figure out the frequency based on number of cylinders, looked up what pitch that corresponded to, and calibrated my own ear via a piano. But I was borrowing my dad’s truck for a day or so - it hardly seemed worth it.
It didn’t have a shift light? Every manual trans car I’ve driven that didn’t have a tach at least had a dummy light. Not sure when those became popular, though.
I don’t think it did.
It was a Mazda B2000 or something of that family - probably from the mid-to-late 1980’s (definitely before the B-Series of Mazda trucks became rebadged Ford Rangers).
(I had forgotten about it, but I believe my 1988.5 Ford Escort had both a tachometer and a shift light. That light came on at really low revs - I felt like I was nearly lugging the engine if I heeded its recommendation. I imagine it was set to maximize fuel economy, performance be damned.)
The redline is the point at which you’re risking damage to your engine, not the point at which you shift for maximum acceleration. In fact, many naturally-aspirated cars can’t even reach the redline in gear on flat ground simply because of how they’re geared and the power band of the engine. Of course, pretty much every car made in the past 25 years or so has EFI that automatically cuts out at the redline.
Under hard acceleration, you should be able to feel when your engine passes the peak of its power band (as the jerk reduces), and you want to shift pretty soon after that. On most cars, the power peak and thus optimum shift point comes long before the redline. The tachometer is potentially helpful if you happen to know at what RPM the engine generates peak HP, but in most cases the ol’ seat-of-the-pants-o-meter is perfectly adequate.
Another thing to consider is that dash space is not really all that “precious” (OP’s term). There’s enough space for everything that needs to be there (unless you’re going to argue that the radio or climate control displays should be there). If you recall, many American cars from the mid-90s or earlier had a wide speedometer that covered most of the dash in front of the driver, plus a small gauge for gas and (usually) one for temperature. I think they came to realize that this made the car (or at least the dash) look somewhat cheap and no-frills. A tach is a relatively inexpensive item to add, and there’s no need for a speedometer to be that big.
I did see a Mazda sedan of some sort in the mid-80s with a shift light. That’s the first time I recall seeing one. The owner of that stuck a piece of tape over it because it was annoying. If you don’t know when to shift without a light telling you then you shouldn’t be driving a stick.
I have an annoying (to me) habit of downshifting my automatic (or “variable shift,” or whatever) car on steep grades. Were it not for a tachometer, I would - out of sheer absent-mindedness - spend a lot of time driving on the highway in first gear.
Fortunately, the car’s CVT (continuously variable transmission) won’t let me blow the engine by passing the redline (I need idiot protection in some things).
Shift lights were there for fuel economy. The one on my Ford Festiva (designed by Mazda, built by Kia) lit up way before the (auditory) redline.