Gearing in 1980s 4-cylinder cars

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My 1964 AH Sprite spun over 4000 RPM @70 MPH. Pretty much worn out at 55,000miles.

I have run my Wife’s 250 Ninja over 9000 RPM all day to cross Texas on I-10. Still running fine @26,000 miles.
 
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brianl703

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There is a 1984 Cavalier still on the road???

Yes, mine. It was my dad's car, a station wagon. I inherited it when he passed away last year. It has about 93K on it. Until earlier this year, it had been parked since 2010, apparently due to a fuel pump failure. Prior to that my dad was driving it about 300 miles a year, based on emissions inspection records. Most of the mileage it has was likely put on it between 1984 and 1991, which is when my mom stopped driving it and got her own car.

Everything works on it, not that there's much to break, this car is so basic.
 
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It's another German or specifically a Mercedes thing. I had the same 4 speed auto in a 190e which was for all intents and purposes a 3 speed. It was a poor auto compared to other contemporary 4 speed autos. I don't know why exactly they have 1st so low as be useless but the trait continues to this day. I have a 2009 6 speed manual and 1st is only good for hill starts. Even the handbook advises that you should set off in 2nd on the flat. Autos are still the same in having a very low 1st gear. They may have resolved the top gear issue by having 9 speeds but they still start off in 2nd meaning they are really only an 8 speed.
Mercedes even did this as recently as 2008 - possibly 2012. The 7G Tronic in my '08 C300 would start out in 2nd if you had it in economy mode, it would drop down pretty quickly to first if you hit the kickdown button from a stop. Sport mode would have it default to 1st from a stop and my experience was that it got better fuel economy driving around sedately in sport mode vs economy. I can't recall if my 2012 E350 started in 2nd or not but part of me thinking it did if in comfort mode (MB changed name from economy to comfort in 2009 or 2010).
 
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I think Mercedes had the diesels start out in 2nd so the torque from the engine wouldn't cause them to creep forward all that much at stop lights. As a general rule if you floored the gas they'd kick down to 1st and give you all the gears.

My 300d w123 wouldn't spend very much time at all in 2nd unless you were really romping on it. More annoyingly, the shifter went PRND31.
 

LDM

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Mercedes even did this as recently as 2008 - possibly 2012. The 7G Tronic in my '08 C300 would start out in 2nd if you had it in economy mode, it would drop down pretty quickly to first if you hit the kickdown button from a stop. Sport mode would have it default to 1st from a stop and my experience was that it got better fuel economy driving around sedately in sport mode vs economy. I can't recall if my 2012 E350 started in 2nd or not but part of me thinking it did if in comfort mode (MB changed name from economy to comfort in 2009 or 2010).
Sounds like the wonderful "Skip Shift" idea that GM came up with on the Corvettes and F-Bodies in the early 90s on the manuals. If you were driving under a certain speed it would lock you out of 2nd and 3rd and force you to shift into 4th gear from 1st. Supposedly it would improve mileage but it was a very annoying feature to say the least. Don't remember anyone liking it and most of us just disabled it with a simple hardware mod on the transmission or in the tune if you had the software and equipment for that. It was the first thing I did on my 94 Z28 after I bought it and got into tuning the PCM.
 
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Had an 89 Cavalier with the 2.0 and 3 speed auto and 185 80 R13 tires.

Lugged at 55, 65 was the sweet spot, and 75 was wondering when a piston was going to come out the hood. For what it was, it was a pretty reliable econobox and was a good first car. Wouldn't want to drive it now, but at the time 😀
 
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Canada, eh?
My '15 Fit with the 6 speed manual wails at 3000 RPM while going 60 MPH, so it's still a thing.
Clearly not as much of a "thing" as Honda has axed the Fit for the N. American market.
As for the rest of the world who still get one, it's all about the CVT's these days.
 

dishdude

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Chrysler must have geared their 80's cars for northeast snowstorms, those things were like snowmobiles. A modern Subaru would be put to shame by an 80's K-car for performance in inclement weather.
 
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At a little over 20mph per 1000rpm this gearing is unreasonably short by modern standards, but it was not uncommon back in the 80's. I had a 1989 2.0 litre Mercedes with similar gearing and I didn't like it. The equivalent car today is geared at 30mph/1000rpm ...
Around 16 mph per 1000 rpm (i.e., 3750 revolutions per mile, or 3750 RPM at 60 mph) was typical of small cars in the 60s and 70s, including my Subaru. By the early '80s, "overdrive" 5th ratios were becoming popular. For example, my 5-speed Mazda GLC (323) did about 23 mph/1000 rpm. However the automatic and 4-speed manual were geared much lower. Later manual cars---for example the manual Fit---regressed on that front.
 
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My '15 Fit with the 6 speed manual wails at 3000 RPM while going 60 MPH, so it's still a thing.
As I mentioned earlier in the thread - the manual Fit is doing 3,000 at 100kph, the CVT Fit is doing 2,000rpm. I drove an 07 iVTEC Fit today - it was doing 1800rpm at 100kph.
 
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If you feather the throttle, and set the cruise exactly right
My Camry will do 2200~rpm @ 70mph
Assuming level ground, and no excessive loads (me in the driver's seat notwithstanding 👀)
Just the right amount of displacement (3.3) and 5 speed auto
Later 2GR/6AT Toyotas were even better
The 2.5 I4/6AT in the Milan will keep it under 2000 @ 60
...until you turn the air on, approach a grade, or slightly tip in
 
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By the early 80's and on, it was very fashionable to have extremely tall top gears on manual trans cars econo cars. At least the ones that received 5 speeds. Automatics had taller final drives but 1:1 top gear on a 3 speed. I had a '67 Ford Cortina GT with a 4.70 final drive and '76 Fiat 128 with alpine gearing around 4.4. With a 4 speed with a 1:1 forth gear it would cost you something close 5k rpm to do 70. 1970's small cars like Corolla, etc. had pretty short gearing as well and didn't do well at Interstate speeds. Nor last long. My '93 Sentra SE-R was short geared and a 1:1 fifth gear. 65 mph was 3500 but that engine could easily handle it.
 
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It's another German or specifically a Mercedes thing. I had the same 4 speed auto in a 190e which was for all intents and purposes a 3 speed. It was a poor auto compared to other contemporary 4 speed autos. I don't know why exactly they have 1st so low as be useless but the trait continues to this day. I have a 2009 6 speed manual and 1st is only good for hill starts. Even the handbook advises that you should set off in 2nd on the flat. Autos are still the same in having a very low 1st gear. They may have resolved the top gear issue by having 9 speeds but they still start off in 2nd meaning they are really only an 8 speed.

The ZF 8HP I had in my 2020 BMW 520d used to pull off in 2nd unless you really gave it the beans or were on an incline. 1st wasn't even that short. It would pull off in 2nd with the T/C open and then close the converter as soon as it changed into 3rd.

Still a smashing gearbox.

That car would be basically idling at 70mph, spinning at 1600rpm.

Still gutted that I had to get rid of it.
 
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Very intersting topic indeed, My 1986 era 6.9L IDI diesel tops out on the governor springs at 3800RPM and about 76 MPH with 4.10 gears. Conversely my friends late model cummins did about 1800 rpm at 75 MPH but i never thought to get the gear ratio.
 
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STL, MO
I had a NB1 Miata that I daily drove for almost 6 years. It had a .81 5th gear, 4.30 final drive, and 23" tires. 75mph equated to 3800 rpm.

It took me a considerable amount of time to get used to this, as my other vehicle at the time was a diesel powered pickup. The number of times I went searching for a non-existent 6th gear on the highway isn't even funny.

I found the RPMs to be pretty annoying at first, but after some time, I started to love it. Now, I'm more annoyed by vehicles that can't hold their speed on inclines in top gear.
 
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