Classic cars forum & vehicle restoration.

[Ray White]

The first car I had with a rev counter was my 1973 Triumph GT6 Mk3. I had been driving for many years before that without the need for one... but with the extra dial I discovered a whole new way of driving.

At first, I was quite keen and after a time, glancing at the 'counter became second nature... but because of the way I had always driven, there seemed to be little point in doing so. I tend to listen to what the engine is telling me, so I don't need a rev counter, for example, to tell me when to change gear.

I found I could use the instrument to tell me what speed I was doing ... but I have a speedo for that. I am also rather slow at mental arithmetics so I just glance at the speedo to check my speed. There again, I am pretty good at judging my speed so the whole exercise becomes rather academic anyway.

As it happens, I have become a rather lazy driver; with my 'modern' being an automatic, I only watch the rev counter to check that the kick down is operating as it should. In an auto it has little other merit as far as I can tell.

There seems to be a certain "machismo" amongst some drivers who seem to have need of a rev counter in order to extract the most from their engines. Despite not being racing drivers, they seem to attach a certain sporting pride to their prowess with this instrument.

Do we have a general opinion on the use of a tachometer?

DO YOU USE YOURS?

[Keith D]

Like Ray, I use my ears rather than a tacho to know how my engine is performing, and drive to keep my engine as stress free as possible. An automatic gearbox really removes any need for a tacho except to 'balance' the facia panel with the speedo.
I will glance at mine when stopped at a noisy, busy intersection to make sure the motor is still running. Otherwise it needn't be there.

Keith D
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1926 Chrysler 60 tourer
1932 Austin Seven RN long wheelbase box sedan
1950 Austin A40 tourer
1999 BMW Z3
Its weird being the same age as old people.
You are either part of the problem or part of the solution

[bjacko]

The only time I use my tacho is to check my speed when the speedometer decides to stop working, otherwise I use my ears.

[badhuis]

On automatics the tacho is not needed.
But in my TR4, it is useful for not getting much over 5000 rpm when accelerating.
I fitted a tacho in my Imp because I wondered how many rpms the engine did. The Imp can have quite high rpms and I found out I could go much higher than I always did. Not that it is necessary but it is nice to know.
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a car stops being fun when it becomes an investment

[Ray White]

Badhuis is right ... up to a point. If the car has an automatic transmission then it does not need to have a tacho fitted as standard equipment... but a tacho IS required for adjusting the down shift cable. However, for most people, the replacement or repair of an automatic gearbox is best left to a garage who will most likely us a hand held version.

[peter scott]

Regardless of what I do to the speedo cable in my SS the reading sways about so I tend to use the rev counter to tell me my exact speed as it is stable and with top gear being 20 mph/1000 rpm I have no difficulty doing the sums.

For many years I was driving on dural rods and decided that I would limit myself to 3500 rpm max so it was useful in giving me a limit that was better defined than my sense of pitch.

I also calibrated the rev counter with a stroboscope so I can trust it better than my speedo. It's useful for setting the idle speed when the engine is cold. I know that it will idle happily at 450 rpm so I can set the hand throttle thus when I switch off the choke.

Peter.
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https://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[Ray White]

[peter scott]

[Ray White]

Thank you for that explanation, Peter. I think having the engine balanced and fitted with steel rods was very wise. The driving experience must have been considerably improved.!

I have had my rebuilt TC engine fully balanced for similar reasons. Although some owners have seen balancing as a way to push the rev range higher, it has been known for a long time that the XPAG engine revved to fast for it's gearing, with the result that it's life is shortened considerably.

I have tried to calm things down where possible and to this end have opted for a higher ratio rear axle (down from 5.12 :1 to 4. 875 : 1) and a 5 speed gearbox. The 40% increase in power gained by using a supercharger should be more than adequate to pull the higher gearing.

Top gear motoring should- as a result of these modifications - be a more relaxed affair and as I tend to not bother with the rev counter much, I have controversially opted to move it's location in the dashboard. No doubt purists will say it is "wrong" - and they have a point - but on the TC the speedo is placed over to the far left where it is not much use.

Taking advantage of the extra length of the speedo cable that came with the T9 gearbox , I am switching over the instruments to allow for easier speedo reading as it will now be in my line of sight.

I am pretty sure MG realised the original layout could be improved upon as the TD - and all subsequent cars - had these two instruments 'close coupled.'

[Rich5ltr]

[mikeC]

The 30mph speed limit was not introduced until 1935, so as you suggest speed was only of minor concern.
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in the garage: 1938 Talbot Ten Airline
Recently departed: 1953 Lancia Appia, 1931 Austin Seven, 1967 Singer Chamois, 1914 Saxon, 1930 Morris Cowley, 1936 BSA Scout, 1958 Lancia Appia coupe, 1922 Star 11.9 ... the list goes on!

[Ray White]

By 1949, when my MG TC was produced, this dashboard layout had become very outdated. MG could have reversed the instruments (like I have) but for whatever reason chose not to.

With speed cameras everywhere I feel somewhat justified in making the change.

I wouldn't be the first to do it.

[peter scott]

[Ray White]

[Crashbox]

Folk are often shocked to learn there were no speed limits on any road between 1930 and 1934. The Highways Act 1930 did away with the 20mph blanket speed limit introduced in 1903, that had replaced the 14mph limit brought in by the Locomotives on Highways Act 1896 (which did away with the 4mph limit and the legal requirement to have one's man walking ahead of one's motorcar waving a red flag). The Motor Car Act 1934 brought in the 30mph limit in built-up areas, but left other roads untouched by any restriction in speed, other than that that one's car can manage... About 50mph in the case of my 1932 Morris Minor!!


The early history of the car is something that fascinates me. I quite fancy a run down to Sussex next weekend to watch the 'Old Crocks' heading down to Brighton. Sadly, the weather doesn't look promising.
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1989 2CV

1932 Morris Minor S.V. Two-Seater