Automatic transmission and "tall" gears

Rouxenator

Rouxenator

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I got a car with an automatic transmission last year but only recently had the opportunity to test it out. It is only a 4 speed so I expected the gears to be pretty long. My last encounter with a 4 speed was a manual 2.1 Microbus and I do recall it had a very long 3rd gear. However it is nowhere near as what I experienced with my new automatic. I enabled "sport" mode which tries to keep revs as high as possible instead of the normal behaviour which is to keep it as low as possible.

When I floored it I found
1st to 2nd at 65km/h
2nd to 3rd at 120km/h
3rd to 4th at 195km/h

When driving under normal conditions the car will hold on to 3rd until the speed drops below 30km/h, with winter mode on it is said the car will pull away in 2nd or 3rd. So in effect this car can actually make do with one gear, being 3rd.

Have to admit that I now see why some people prefer automatics, it is very relaxing to drive and they are very capable. Anyone else found that their autos also have such tall gears?
 
It's a 2007 Astra H 1.8 (Z18XER 103kw) with 63,000km on the clock. Took a video on a private road when I gave it some foot. Had a massive head wind so as soon as it shifts to 4th the speed drops and once it goes below 190km/h it shifts down to 3rd.
[video=youtube;824UijAccEM]https://www.youtube.com/watch?v=824UijAccEM[/video]
 
Rouxenator said:
It's a 2007 Astra H 1.8 (Z18XER 103kw) with 63,000km on the clock. Took a video on a private road when I gave it some foot. Had a massive head wind so as soon as it shifts to 4th the speed drops and once it goes below 190km/h it shifts down to 3rd.
Click to expand...

is this a CVT? that would explain it, drove a jazz once and I remember only kickdown to 2nd when you leave pedal, almost always in 3rd.

weird driving an auto, as you forget theres no clutch; suppose its what your used to that matters;
 
eg2505 said:
is this a CVT? that would explain it, drove a jazz once and I remember only kickdown to 2nd when you leave pedal, almost always in 3rd.

weird driving an auto, as you forget theres no clutch; suppose its what your used to that matters;
Click to expand...

CVT's don't shift. They have no gears. It continuously varies the ratio and keeps the revs constant, depending on how much you floor it. High revs if you floor it, lower revs if you lift your foot.
 
Correct, this is not a CVT transmission. I am surprised that it has a gear that can cover everything from 30km/h to 195km/h. Obviously it does have a penalty on your consumption.
 
Quantum Theory said:
CVT's don't shift. They have no gears. It continuously varies the ratio and keeps the revs constant, depending on how much you floor it. High revs if you floor it, lower revs if you lift your foot.
Click to expand...

now I understand; felt really strange it just accelerates and no feeling at all; except when you kickdown;
then is feels like a cog is dropped and it accelerates;

still prefer manual cars; auto is great for traffic; no clutch/clutch cable to wear out;

I do hear its impossible to kickstart; and towing is an issue; never owned an auto so not so sure.
 
Rouxenator said:
Correct, this is not a CVT transmission. I am surprised that it has a gear that can cover everything from 30km/h to 195km/h. Obviously it does have a penalty on your consumption.
Click to expand...

Not too uncommon for cars with fewer ratios.

Drove a Mazda 323 3-speed many years that would do 60-160 in third.
 
Rouxenator said:
I got a car with an automatic transmission last year but only recently had the opportunity to test it out. It is only a 4 speed so I expected the gears to be pretty long. My last encounter with a 4 speed was a manual 2.1 Microbus and I do recall it had a very long 3rd gear. However it is nowhere near as what I experienced with my new automatic. I enabled "sport" mode which tries to keep revs as high as possible instead of the normal behaviour which is to keep it as low as possible.

When I floored it I found
1st to 2nd at 65km/h
2nd to 3rd at 120km/h
3rd to 4th at 195km/h

When driving under normal conditions the car will hold on to 3rd until the speed drops below 30km/h, with winter mode on it is said the car will pull away in 2nd or 3rd. So in effect this car can actually make do with one gear, being 3rd.

Have to admit that I now see why some people prefer automatics, it is very relaxing to drive and they are very capable. Anyone else found that their autos also have such tall gears?
Click to expand...

Remember the 2nd or 3rd gear is for frosty places as there is hardly any traction. In my Bakkie though I can pull away in 2nd or even third due to the torque. i can't see how an 1.8 would have that power unless its in low grip areas.

Edit, just to add my Bakkie is Manual. From having experience with A/T's Normally it would change as it picks up speed. if you need to grea down you just to a step down (stepping the fuel all the way down and it forces a change back to a lower more powered gear.
 
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While on the topic - would do cars have gears that go way beyond legal speed limit? Surely a bunch of very short gears would be better for actual driving on streets - esp with the dual ones that you don't really feel shift.

Ignoring the race day & bragging aspect for a sec...
 
I think that is exactly why modern automatics are 7 or 8 speed, for better real world driving using shorter gears. My car is 8 years old and was one of the last Astras to come with a 4 speed (60-40LE). The following year they switched to 6 speed which was never imported to SA.

About pulling away in 3rd when on winter mode, I did not believe it either but I checked the manual and it said "Press the Frost button with P, R, N, D or 3 engaged. The vehicle starts off in 3rd gear." I guess as dj_jyno said it all comes down to the fact that these cars have a torque converter and the engine is not directly connected to the wheels as in a manual with clutch setup.
 
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Rouxenator said:
I think that is exactly why modern automatics are 7 or 8 speed, for better real world driving using shorter gears.
Click to expand...

I've got a video somewhere, of a 7 speed DSG, floored to about 140km/h (private road obviously)... Might post it later.
 
HavocXphere said:
While on the topic - would do cars have gears that go way beyond legal speed limit? Surely a bunch of very short gears would be better for actual driving on streets - esp with the dual ones that you don't really feel shift.

Ignoring the race day & bragging aspect for a sec...
Click to expand...

Well in modern automatics it makes more sense.

But can you imagine changing 7 -8 gears yourself?

6 was already a push which is why it was imply a cruise gear in most cars.
 
I think there is a 7 speed manual Corvette, but most manual cars are either 5 speed or 6 speed. Way back when I was young my grand dad had a 3 speed manual Ford Ranchero, I can imagine back when it came out people would think 5 speed is too much.

QT I would like to see the 7 speed DSG clip, taken on a private road of course.
 
eg2505 said:
I do hear its impossible to kickstart; and towing is an issue; never owned an auto so not so sure.
Click to expand...
You can jump start but not push start. Towing as per manual : "Vehicles with automatic transmission must be towed facing forwards, not faster than 80 km/h nor further than 100 km. In all other cases and when the transmission is defective, the front axle must be raised off the ground"
 
Rouxenator said:
I think there is a 7 speed manual Corvette, but most manual cars are either 5 speed or 6 speed. Way back when I was young my grand dad had a 3 speed manual Ford Ranchero, I can imagine back when it came out people would think 5 speed is too much.

QT I would like to see the 7 speed DSG clip, taken on a private road of course.
Click to expand...

You get a 7-Speed Manual C7 Corvette Stingray as well as the Porsche (991) 911 has a 7-Speed Manual option.
 
I find most cars with less than 6 gears (Spanish spec or auto) annoying as hell, the only exception being some tiny engines that can't really justify a long 6th.

Bring on reliable 20 speed boxes (in manual, so we can replicate "The Fast and Furious" races)!
 
7 or 8 speed gearboxes are not about having longer gears. They're about giving the engine the most chance to operate at its most efficient RPM (torque peak) - so the ratios are closer together, which causes less rpm drop between gears.
 
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