Oh I had forgotten about them, I remember coming to drive one, looked at little gear stick R - D, 1 - 2, 3 - 4 so not going to mess around, so put it in D, all that happened was the doors opened.
Not sure we are singing from the same hymn sheet here.
If by 'them' you are referring to the Ventora I'm talking about the FD model Vauxhalls' manuf. from the late 'sixties through to the early 'seventies. If on the other hand it's the ZF's then I don't recognise your description of the shift layout.
Never mind, it's not important at the end of the day
Automatic
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Me thinks in effort to get to speed without holding others up you are going into 'Kickdown' mode. With todays small, turbocharged engines to develope what is deemed to be acceptable performance high revs with lots of noise is the norm.
What is the peak torque RPM for the car - is that the point the engine revs to when you accellerate?
I've driven auto's for years (including BorgWarner slush box's, DSG's, CVT's, ZF auto's). Present cars in the household are Honda Jazz CVT - put foot down but not to 'Kickdown' point- revs climb quickly to 4000 and sits around that point 'till car is about at speed for the throttle opening when the revs reduce but the speed remains pretty constant; If accellerating from that speed revs again will rise to 4000 to 4500 RPM until throttle is closed a little or speed is acheved. If the throttle goes past the kickdown point the revs and engine noise rise and the revs rise to Redline (6750) when the CVT setpoint changes and effectively 'changes' down with the revs rising again to Redline. Much over 90MPH it never reaches highest ratio.
Other car is a Honda Civic of previous generation, has a 5 speed Honda modified BW box - again on fast acelleration revs to 4000RPM but with positive change points, in kickdown it holds each gear to about 6500RPM before doing a upchange. On modrate accelleration the revs rise to around 3000rpm and the car allows to Torque Converter to build the speed.
Interestingly this is the only automatic car I've driven that changes down on overspeed - i.e. when descending steep hills and the like.
Perfectly normal. If you put your foot down, then the autobox will assume you are wanting close to maximum acceleration, and oblige you by running the engine in the best power band. Once you ease of your demand, it changes up for better economy.
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@norseman no the door opening was on a bus, not car, in early years did not see diesel automatics with cars, although 1980 USA style school bus I drove in Algeria was fully automatic, but British buses were semi-automatic. The DAF belt drive was also used with Volvo, Ford and Honda, although moved to stainless steel belt not rubber, but same idea, these boxes did not seem to kick down in the same way as the epicyclic gear boxes. Large engine cars only used 2 gears the third was only for towing, and the way the boxes worked resulted in needing the read the manual, the Morris Mariana from memory you could manually put in low, as braking and it would only change down once road speed low enough, however this was not the case with the Mini automatic, doing same with that car would likely wreck the engine, plus free wheel on first gear.
I have driven faulty and poorly set up automatics, and have stripped one and replaced the clutch plates in a Rover 3500 after it was towed, some automatics had two oil pumps and could be push started, others towing them would wreak the box due to no lubrication as no oil pump on output shaft.
Putting on a recovery vehicle in Park could also wreak the box.
But today with 8 speed boxes the way the automatic drives is very different from years ago. I drive a manual diesel and to keep revs low enough so turbo not running so does well with miles per gallon one is playing tunes on the gear box changing gear many times driving in Welsh hills, the automatic in the Jag means we are unaware when the gear changes, when we first got it I tried working out what gear I was in, but could not keep count, never tried using paddles. The whole idea is it does it all for you.
So early automatics used more fuel than the manual, but today's automatic uses less fuel to manual version, things have moved on. But the big thing I have realised they are not all the same, and the only option is to read the book on the version you have, in the main yes engine will rev up as you accelerate, but the old idea of kick down has in the main gone, you don't need to press the throttle rapid any more for it to work, the system is far better at working out what engine speed is required to get acceleration and yes I know with the 8 speed it does some times change two speeds at a time, so there is no common answer to the question.
I have driven faulty and poorly set up automatics, and have stripped one and replaced the clutch plates in a Rover 3500 after it was towed, some automatics had two oil pumps and could be push started, others towing them would wreak the box due to no lubrication as no oil pump on output shaft.
Putting on a recovery vehicle in Park could also wreak the box.
But today with 8 speed boxes the way the automatic drives is very different from years ago. I drive a manual diesel and to keep revs low enough so turbo not running so does well with miles per gallon one is playing tunes on the gear box changing gear many times driving in Welsh hills, the automatic in the Jag means we are unaware when the gear changes, when we first got it I tried working out what gear I was in, but could not keep count, never tried using paddles. The whole idea is it does it all for you.
So early automatics used more fuel than the manual, but today's automatic uses less fuel to manual version, things have moved on. But the big thing I have realised they are not all the same, and the only option is to read the book on the version you have, in the main yes engine will rev up as you accelerate, but the old idea of kick down has in the main gone, you don't need to press the throttle rapid any more for it to work, the system is far better at working out what engine speed is required to get acceleration and yes I know with the 8 speed it does some times change two speeds at a time, so there is no common answer to the question.
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For a short while I had one of those early DAF's - I hated it with a vengence. My tractor mower uses the same principle and for that it seems appropriate.
I'll stick to my diesel manual, chugging along nicely at between 1,000 and 2,000 RPM and leaving most people chewing my dust.
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Most the big stuff has to be automatic, there is a limit what a clutch can handle, and how long you can send power through a fluid flywheel or torque converter, the manual is often really an automatic, you may have paddles to change gear, but in real terms you say I would like 6th gear then the engine management decides if you can have it.
If you have a 1000 HP Deltic your not going to use a manual clutch, I remember we had some V12 CAT dump trucks, with pneumatic, hydraulic, electronic control for the 24 speed gear box and I prayed it never went wrong, they never did, it does seem strange the way road wagons used a clutch for many years, but the rail engines could not work with the much heavier loads with a clutch. Yet the cars seemed to hang onto the manual box to present day, yet little Honda 50 were semi-automatic.
But to change through 8 gears selecting best option may be great fun on the race track, but normal driving no one wants to be changing up and down that often, it was OK in the days of steam when main line engines had no gears, and even traction engines likely only 2, then the petrol engine for many years 3 or 4 gears, then to get economy it slowly moved to 5 and 6, wagons had range change and two speed rear axils, and if you have ever miss judged one and ended up between the two speeds and no engine braking you would realise why not such a good idea.
The idea of judging the blur on the straight cut gears and changing ratio with a traction engine may have some romantic appeal, until you realise the brakes were near enough useless and you stopped them by putting engine in reverse, so miss a gear and no brakes.
Even with e-bikes there is the big debate, in the hub so no strain on chain, or in the crank set so you can gain the advantage on the hills.
If you have a 1000 HP Deltic your not going to use a manual clutch, I remember we had some V12 CAT dump trucks, with pneumatic, hydraulic, electronic control for the 24 speed gear box and I prayed it never went wrong, they never did, it does seem strange the way road wagons used a clutch for many years, but the rail engines could not work with the much heavier loads with a clutch. Yet the cars seemed to hang onto the manual box to present day, yet little Honda 50 were semi-automatic.
But to change through 8 gears selecting best option may be great fun on the race track, but normal driving no one wants to be changing up and down that often, it was OK in the days of steam when main line engines had no gears, and even traction engines likely only 2, then the petrol engine for many years 3 or 4 gears, then to get economy it slowly moved to 5 and 6, wagons had range change and two speed rear axils, and if you have ever miss judged one and ended up between the two speeds and no engine braking you would realise why not such a good idea.
The idea of judging the blur on the straight cut gears and changing ratio with a traction engine may have some romantic appeal, until you realise the brakes were near enough useless and you stopped them by putting engine in reverse, so miss a gear and no brakes.
Even with e-bikes there is the big debate, in the hub so no strain on chain, or in the crank set so you can gain the advantage on the hills.
CVT is a horrible design, a suitably sized Diesel engine mated to a decent DCT Twin Clutch geabox can be driven everywhere at 2000 rpm or less.
As said a Petrol engine too small for the car has to be rinsed to get anything close to acceptable acceleration, coupled to a CVT it's no wonder it's revving it's knackers off..
As said a Petrol engine too small for the car has to be rinsed to get anything close to acceptable acceleration, coupled to a CVT it's no wonder it's revving it's knackers off..
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