Page 1 of 2
Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 3:32 pm
by mik
Prompted by the discussion on the new 992.2 and the switch from physicals dials to LCD (with only some of the view options including a rev-counter).
(Note: I am using "auto" as a generic terms for non-manuel. Please don't get all excited about PDK vs torque converters etc etc).
Obviously tachometers are essential for manuels (and cars with paddle-shift that have modes that wait for your inputs and don't auto-shift - even if that leaves you bouncing off the limiter), but are you bothered if the car shifts for you?
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 4:01 pm
by GG.
Also useful for knowing exactly when you are at 3800 revs at 3/4 throttle to make the engine do its "waaaaaah" noise. Obviously I'm not referring to the RR there...
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 4:17 pm
by ZedLeg
Rev counters are nice to have but not essential imo.
Even if you’re Out For a Drive you won’t always be looking at the rev counter for gearchanges etc.
Noise and familiarity with the car play their part.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 4:18 pm
by mik
GG. wrote: Thu May 30, 2024 4:01 pm
Also useful for knowing exactly when you are at 3800 revs at 3/4 throttle to make the engine do its "waaaaaah" noise. Obviously I'm not referring to the RR there...
Yes, we realised you meant the Smart

Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 4:22 pm
by mik
If I am driving an auto with paddles I find I generally let the car do it's thing > there isn't much tactile enjoyment from flicking a paddle.
caveat1: unless I am towing, and the car's decisions are generally inappropriate
caveat2: unless Pete @revsRus lets me look after his 600LT again - that's the most I've ever actively used paddles in an auto
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 4:49 pm
by Jobbo
Only essential in an EV I think.
But seriously, if I have an engine I want to know what it's doing. It's not just useful for getting into the power band, it's useful to know when the stop/start has turned it off completely or when you're in a lower gear than you expect to be at a cruise, indicating something is wrong.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 6:23 pm
by integrale_evo
I like mine, makes it exactly like an M5

Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 6:27 pm
by Sundayjumper
Mine goes backwards

- IMG_6869.jpeg (68.45 KiB) Viewed 752 times
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Thu May 30, 2024 7:05 pm
by jamcg
Sundayjumper wrote: Thu May 30, 2024 6:27 pm
Mine goes backwards
IMG_6869.jpeg
Once a year on the way to the mot centre
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 9:50 am
by scotta
The 1 series comes from the factory with a power meter as default in "Comfort" mode. Its the first thing i changed to show revs.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 11:04 am
by V8Granite
I use it all the time when towing as it normally wants to be in 1 gear too high.
For playing I generally keep it below 4500 and only go to the limiter if the kids demand it. It adds a bit of enjoyment if you can slightly lift and get it to change up.
In the old auto 500e I use it more as I generally only use 2nd and 3rd when playing.
Dave!
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 11:21 am
by dinny_g
I’d say even for manuals, they’re only useful for about the first 500 or so miles until you get to know your engine, then pretty much useless (towing example aside)
Engine noise, speed, rate of acceleration, even time since last gear change… some or even all of these are used to know when to change up or down.
You shouldn’t really need to look down at a rev counter
Pointless in an Auto
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 11:35 am
by Sundayjumper
dinny_g wrote: Fri May 31, 2024 11:21 am
Engine noise, speed, rate of acceleration, even time since last gear change… some or even all of these are used to know when to change up or down.
You shouldn’t really need to look down at a rev counter
I agree with this. If you're thrashing it to the point you're constantly near the redline you should probably be looking where you're going, not staring at the dash
That's why shift lights got invented, you register the light in your peripheral vision without taking your eyes off the road/track. The
actual engine speed is not enormously important.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 11:56 am
by V8Granite
Do people really look at the Rev counter or can you see it in your peripheral ?
You don’t stare at it you can just see it.
Dave!
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 12:04 pm
by Jobbo
Sundayjumper wrote: Fri May 31, 2024 11:35 am
dinny_g wrote: Fri May 31, 2024 11:21 am
Engine noise, speed, rate of acceleration, even time since last gear change… some or even all of these are used to know when to change up or down.
You shouldn’t really need to look down at a rev counter
I agree with this. If you're thrashing it to the point you're constantly near the redline you should probably be looking where you're going, not staring at the dash
That's why shift lights got invented, you register the light in your peripheral vision without taking your eyes off the road/track. The
actual engine speed is not enormously important.
The question was whether the rev counter was useful, not whether the red line was useful. And since rev limiters came into being, the red line isn't as useful as all that.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 12:09 pm
by Mito Man
Let’s be honest the only thing it’s useful for is to satisfy one’s curiosity

Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 12:15 pm
by Jobbo
GG mentioned the oil pressure gauge in his 911 so I wonder whether there may be other useful instruments which have disappeared and we don't miss? My mk1 MX5s had oil pressure gauges which made me happy that there was oil pressure I suppose, but I didn't keep an eye on. Oil temp and turbo boost are visible in my Audi if I expand the dash display but I only look at that screen to see if it's doing a DPF regen. BMW did away with water temperature gauges a while ago, IIRC.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 12:37 pm
by GG.
Jobbo wrote: Fri May 31, 2024 12:15 pm
GG mentioned the oil pressure gauge in his 911 so I wonder whether there may be other useful instruments which have disappeared and we don't miss? My mk1 MX5s had oil pressure gauges which made me happy that there was oil pressure I suppose, but I didn't keep an eye on. Oil temp and turbo boost are visible in my Audi if I expand the dash display but I only look at that screen to see if it's doing a DPF regen. BMW did away with water temperature gauges a while ago, IIRC.
Yep - the much more useful one is oil temperature rather than pressure so you're not hooning it before its up to temperature - the 911 takes a
looong time for the oil to get completely warm.
The wonderful irony is though that I'm not actually looking at the analogue guagues - I toggle the LCD screen in the cluster right of the rev counter which displays that information much more clearly.
Battery charge is another useful one though pretty rare I think. I can see looking at my trackers interestingly which give me the current voltage of the main battery.
Front wheel / Rear Wheel split on the 4WD is mildly interesting. G meter completely pointless unless you're on a track.
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 12:41 pm
by mik
GG. wrote: Fri May 31, 2024 12:37 pm
Yep - the much more useful one is oil temperature rather than pressure so you're not hooning it before its up to temperature - the 911 takes a
looong time for the oil to get completely warm.
VXR8 had battery voltage, oil pressure, and oil temp. I'd agree the latter was most useful.
One of the reasons I got an wifi obd dongle was to try and get this info in the Evora - although I then found it's best to do your research before purchasing it, as there isn't an oil temp sensor in the powerplant
(It's proved very useful anyway so wasn't money wasted).
Re: Do automatic ICE cars need tachometers/rev-counters?
Posted: Fri May 31, 2024 3:19 pm
by Sundayjumper
Jobbo wrote: Fri May 31, 2024 12:04 pm
Sundayjumper wrote: Fri May 31, 2024 11:35 am
dinny_g wrote: Fri May 31, 2024 11:21 am
Engine noise, speed, rate of acceleration, even time since last gear change… some or even all of these are used to know when to change up or down.
You shouldn’t really need to look down at a rev counter
I agree with this. If you're thrashing it to the point you're constantly near the redline you should probably be looking where you're going, not staring at the dash
That's why shift lights got invented, you register the light in your peripheral vision without taking your eyes off the road/track. The
actual engine speed is not enormously important.
The question was whether the rev counter was useful, not whether the red line was useful. And since rev limiters came into being, the red line isn't as useful as all that.
Really not the point
