German Car Zone

My 190E with four speed trans and 3.23 diff runs 4000RPM at 84MPH.
I wish the gearing was different so that it actually used first gear and that the RPM was lower at freeway speed.

That's just like my Audi...but the bad thing is that a little more rpm on my car and I'll be in the turbo range.

Yeah, five speeds is just right. 3 or 4 is a bit short.

But I find 7 or 8 speeds to be useless. It's what, 100rpm less in 7th than 6th, and the car always starts in second...

Now that's a thing I never understood: many many MBs are starting in 2nd unless you flatten the throttle.
Why is that? I'd be very interested by any explanation.

Might be for better traction. In Volvo V70 the W (as in winter mode) sets the transmission to start with the second gear. It helps a lot during city traffic in snow. Wheels don't spin nearly as much as they would from the first gear up. I bet the issue is even greater when we are talking about RWD which has naturally lower traction in snow than FWD.

The reason why some Mercedes cars accelerate from 2nd gear is because it gives a more relaxed, comfortable and smoother off-the-line acceleration for the passengers. The car would build up a steady and almost unnoticeable acceleration off-the-line which gives a 'woosh' kind of feel. A luxury/comfort kind of acceleration, perfect for city driving.
If you put the car in sport mode or full throttle, the first gear will be engaged and the off-the-line acceleration will be more abrupt, responsive, nervous and sudden. Not so relaxing, comfortable and smooth when cruising but gives a better off-the-line start and a sporty acceleration.

Yeah that's what i thought too. But it seems a very complicated way of achieving a smooth drive-off.

Wouldn't it be a better solution to have a slighly longer first gear (compromise between urge and smoothness)? 'Cause when you have only four gears, but that the third is not used, you end up with high rpm at cruising speed, for a dubious benefit in terms of comfort when you start.

I thought there might be another explanation, because this one doesn't really convince me. Maybe this also was done for easier trailing with a short first gear?

The trade off seems higher than the benefit for this solution.

Does the 5G start in second? I believe no, unless in Winter mode. The 7G does start in second.

Are the other carmakers also using second-gear start with less-than-6 gearboxes?

In my opinion it's actually the easier way of achieving a smooth drive especially if you only have an automatic gearbox with only 3 to 4 gears.
You have less room to optimize the gears with the engine power and acceleration.

If you make the first gear a bit longer, then the 2nd, 3rd and 4th gears needs to be adjusted as well so that all the gears in the gearbox are complementary and harmonize with each other. This means that the 2nd, 3rd and 4th gear will be longer, giving a lower rpm when cruising on highway.
However this would give the car a feeling being slow, sluggish concerning acceleration off-the-line and highway overtaking.
And when people buy a car, the performance figures on paper and the overall feel of the car's performance is really something that matters to people even back in the days and presently.

Another reason would be is that the engine back in the old days were all mechanical and not controlled by an ECU.
For some period of time I've owned a 1990 Mercedes-Benz 190E 1.8, manual.
It was a very basic car, almost everything was mechanical even the windows and the car never had let me down once.
A good car but it does not have any punch down low in the rpm. If you are driving and shift the car to 2nd gear or 3rd gear so that the engine only turns slightly below 1500 rpm, the whole car would judder heavily as if it's going to stall.
Then for some time I switched to an 1996 Mercedes-Benz C180, manual. It was quite a difference, the engine was much smoother and more capable. When I accelerated in 2nd gear or 3rd gear below 1500 rpm it was free of judder as if pulling out of the low rpm was no problem at all.
I can't really speak for the larger engined cars back in the days like the SL450 or the 560SEC since I've never driven any of the cars.
But with the same thought in mind, I think that was also the reason why the gearing in the older cars were much shorter than present cars, to prevent the car from stalling by having the engine turning higher rpm's.
Since the engine was controlled mechanically and not electronically by an ECU. Modern engines are more capable turning lower rpm than older engines.

Further we are talking about cars with only 3 to 4 gears meaning we are talking about cars that are at least 20 years old. Aren't almost all cars back in these days have relatively high cruising rpm compared to modern cars. Fuel consumption wasn't really that much of an issue compared to how it is now.

Well that makes sense for smaller engines, that's right.

But for big ones, I don't think it does.

My car has a 3-gears slushbox, that was replaced some years after by a 4 one (starting in second).

However, the gearbox of my car engages the third at around 50 km/h, not more. And it doesn't feel slow in normal conditions. Only if you are in a real hurry does the gearbox downshift to 2nd.

It means that the car could suffer a real fourth gear with no problem. A gear that would be engaged at around 70 km/h for instance, wouldn't make it a slow pig considering the torque, power and feeling of the car.

Yet the fourth gear of more recent models starts in 2nd, meaning it's no real four-gear IRL. That I don't really understand.

Another thing is that ,back then, the mechanical throttle was much harder to push, and had more course than the current electronical ones. it was easier to dosate, and I never have "brutal" startings when I don't want to, thanks to the ample course and solid feel of the pedal.

So really, on sufficiently powerful models like all the 380, 450, 500 and co, I don't see the point of this second gear start when the gearbox has already quite few gears.

Feels like a spoiled, useless gear to me, that would be much more needed at the other side of the speed range.

Maybe it would 've been too hard to make it reactive enough at higher speed (where you need the gearbox to act fast, on a hill or for an overtaking, while not switching constantly for no apparent reason), while 4 sounds much better than 3 where all manual gearboxes have 5 speeds, despite the fact that it in fact feels like a 3-gears? The softwares were much simpler back then than now, where 7 or 8 speeds are no problem from an electronic/software PoV?

5G starts in first or second depending on the W/S C/S switch.
7G starts in first or second depending on the C/S switch.

Yeah, if I remeber well the 5G starts in 1st unless you put it in Winter mode, whereas the 7G starts in second unless put in sports mode, is that right?