Questions tagged [gear-ratio]
17 questions
15
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4 answers
Why do 5 and 6-speed transmissions typically need different gear ratios?
My 2013 Subaru WRX has a 5-speed manual, and I long for it to have a 6th gear when cruising on the highway.
A friend has a 2012 Subaru STI with a 6-speed manual, and I noticed his car runs through the gears more quickly to achieve the same…
Trevor D
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Is reverse gear in a manual transmission equivalent to any other gear?
Question is pretty well summarized in the title.
If we were to order gears in terms of power provided, where would reverse fall between gears 1-5 on a manual transmission vehicle?
Does it vary by vehicle?
CaptainCalvert
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Optimal RPM range for manual transmission
Are there optimal RPM ranges for different vehicles? I've been told it's better for the engine to drive at slightly higher RPMs (e.g. 2500-3000 for my Tacoma) than low (1000-1500).
I understand a lot depends on the gear sizing and ratios for…
amphibient
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How come gears don’t normally change in an automatic car?
I know that there is a similar question here, and another one here that asks when an automatic gearbox knows how to change gear, but I want to know exactly how it does that.
It was brought to my attention recently that the gears don't "shift" in an…
Max Goodridge
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6
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Does an increase in horsepower allow a greater speed in any given gear?
I wasn't sure if this was the best place to post this, or if I should go post it in the physics stackexchange as well. I can crosspost if this question would be more fitting over there.
To put this question in context, take my car for example.…
Baylor Norris
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Why can a motorcycle rev higher than a car, in spite of both reaching the same speed?
Basically, a car (street legal 2.5L) has about 7k RPM on its tachometer and a Motorcycle has about 14k RPM. Why is there a difference?
Is there any relation between the displacement of the engine and the weight of the vehicle?
Moreover, how can…
BraveNinja
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Why after a certain RPM with the same gear selected the car no longer accelerates?
I have basic understanding of gearboxes and why we use them, but what is baffling me is that after about 4000 RPM (at least in my car) it doesn't accelerate further (or it does slowly)... This seems to apply to any kind of gearbox. For example in…
Wimp6612
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Why does the wheel size affect the cars gearing?
Using online gearing top speed calculators I realized that the bigger the diameter of the wheels, the higher the theoretical gearing top speed is. Why is that? Why does bigger wheel act as increasing the gear ratio and thus increasing the…
Timothy Scherer
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Does increasing final drive ratio actually improve overall acceleration?
Hopefully, this is the correct forum to ask this. There's lots of stuff online about final drive ratios, but not much with respect to actual acceleration times, and usually it's just anecdotal, butt-dyno kind of stuff.
I understand that increasing…
bertmoog
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is primary drive ratio included within the gear ratio specs?
Is primary drive ratio normally included into the gearbox ratio specification, or should it be considered as a sum of the two to get the true ratio?
Lets take a modern BMW motorcycle engine as an example - what would be a gearbox output ratio at…
FlegmatoidZoid
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2
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Transmission replacement and changing gear ratios
I have 1998 Dodge Durango. It's a 4x4 5.9L v8. I'm looking at replacing the transmission and seeing as I don't really need 4wd in the city, I'd like to get better fuel economy and better acceleration.
The question is whether or not it's cost…
Andrew Graham
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What is the redline for different gears for Peugeot 107 2005 model?
I have a Peugeot 107 which is a 1 liter engine car.
I was wondering what is the maximum safe speed at different gears?
The car starts to make a lot of noise in 1st and 2nd gear, even at 10 mph at 2nd gear the car makes too much noise.
BhupinderTube
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Transmission Slipping, Mechanic Claims it needs re-build, then it suddenly starts working again - 2000 Nissan Xterra
The transmission on my 2000 Nissan Xterra with 114,000 miles randomly started slipping one day. It does seem to be slipping somewhat in all gears, but it's most prominent in 2nd and 3rd. If I keep holding down the pedal, the RPM's keep increasing…
Josh Zeldin
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Is the 2KD engine manual gearbox compatible with a 1KD?
The car is a Hilux Vigo 4WD , manual transmission.
Can I use a manual 5-gear gearbox that is designed for a 2.4L (2KD) engine with a 1KD 3.0L engine?
A duplicate post of this question : https://engineering.stackexchange.com/q/19658/10902
mykey
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Why my bike shows petrol missing before 2000 RPM in all gears?
I am using Hero Karizma R (225cc, 5 gears).
Recently I feel a missing in all gear befor 2000 RPM. Sometimes my bike turn off due to this missing. Usually it happens at 1st/2nd gears. After 2000 RPM there is no problem. I checked it in a road by…
kannan
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