Sh*t 86 Owners Say

[Tcoat]

Originally Posted by Tcoat

OP:
"I am new to driving manual what should I know?"


Reply:

"The simplest example of a gear train has two gears. The "input gear" (also known as drive gear) transmits power to the "output gear" (also known as driven gear). The input gear will typically be connected to a power source, such as a motor or engine. In such an example, the power output of the output (driven) gear depends on the ratio of the dimensions of the two gears.


The teeth on gears are designed so that the gears can roll on each other smoothly (without slipping or jamming). In order for two gears to roll on each other smoothly, they must be designed so that the velocity at the point of contact of the two pitch circles (represented by v) is the same for each gear.
Mathematically, if the input gear GA has the radius rA and angular velocity , and meshes with output gear GB of radius rB and angular velocity , then:
The number of teeth on a gear is proportional to the radius of its pitch circle, which means that the ratios of the gears' angular velocities, radii, and number of teeth are equal. Where NA is the number of teeth on the input gear and NB is the number of teeth on the output gear, the following equation is formed:
This shows that a simple gear train with two gears has the gear ratio R given by
This equation shows that if the number of teeth on the output gear GB is larger than the number of teeth on the input gear GA, then the input gear GA must rotate faster than the output gear GB.
Gear teeth are distributed along the circumference of the pitch circle so that the thickness t of each tooth and the space between neighboring teeth are the same. The pitch p of a gear, which is the distance between equivalent points on neighboring teeth along the pitch circle, is equal to twice the thickness of a tooth,
The pitch of a gear GA can be computed from the number of teeth NA and the radius rA of its pitch circle
In order to mesh smoothly two gears GA and GB must have the same sized teeth and therefore they must have the same pitch p, which means
This equation shows that the ratio of the circumference, the diameters and the radii of two meshing gears is equal to the ratio of their number of teeth,
The speed ratio of two gears rolling without slipping on their pitch circles is given by,
therefore
In other words, the gear ratio, or speed ratio, is inversely proportional to the radius of the pitch circle and the number of teeth of the input gear.
A geartraincan be analyzed using the principle of virtual work to show that its torque ratio, which is the ratio of its output torque to its input torque, is equal to the gear ratio, or speed ratio, of the gear train.
This means that the input torque ΤA applied to the input gear GA and the output torque ΤB on the output gear GB are related by the ratio
where R is the gear ratio of the gear train
The torque ratio of a gear train is also known as its mechanical advantage
In a sequence of gears chained together, the ratio depends only on the number of teeth on the first and last gear. The intermediate gears, regardless of their size, do not alter the overall gear ratio of the chain. However, the addition of each intermediate gear reverses the direction of rotation of the final gear.

An intermediate gear which does not drive a shaft to perform any work is called an idler gear. Sometimes, a single idler gear is used to reverse the direction, in which case it may be referred to as a reverse idler. For instance, the typical automobile manual transmission engages reverse gear by means of inserting a reverse idler between two gears.
Idler gears can also transmit rotation among distant shafts in situations where it would be impractical to simply make the distant gears larger to bring them together. Not only do larger gears occupy more space, the mass and rotational inertia of a gear is proportional to the square of its radius. Instead of idler gears, a toothed belt or chain can be used to transmit torque over distance.
If a simple gear train has three gears, such that the input gear GA meshes with an intermediate gear GI which in turn meshes with the output gear GB, then the pitch circle of the intermediate gear rolls without slipping on both the pitch circles of the input and output gears. This yields the two relations
The speed ratio of this gear train is obtained by multiplying these two equations to obtain
Notice that this gear ratio is exactly the same as for the case when the gears GA and GB engaged directly. The intermediate gear provides spacing but does not affect the gear ratio. For this reason it is called an idler gear. The same gear ratio is obtained for a sequence of idler gears and hence an idler gear is used to provide the same direction to rotate the driver and driven gear, if the driver gear moves in clockwise direction, then the driven gear also moves in the clockwise direction with the help of the idler gear.
Assuming that smallest gear is connected to the motor, it is the driver gear. The somewhat larger gear on the upper left is called an idler gear. It is not connected directly to either the motor or the output shaft and only transmits power between the input and output gears. There is a third gear in the upper-right corner of the photo. Assuming that that gear is connected to the machine's output shaft, it is the output or driven gear.
The input gear in this gear train has 13 teeth and the idler gear has 21 teeth. Considering only these gears, the gear ratio between the idler and the input gear can be calculated as if the idler gear was the output gear. Therefore, the gear ratio is driven/driver = 21/13 ≈1.62 or 1.62:1.
This ratio means that the driver gear must make 1.62 revolutions to turn the driven gear once. It also means that for every one revolution of the driver, the driven gear has made 1/1.62, or 0.62, revolutions. Essentially, the larger gear turns more slowly.
The third gear in the picture has 42 teeth. The gear ratio between the idler and third gear is thus 42/21, or 2:1, and hence the final gear ratio is 1.62x2≈3.23. For every 3.23 revolutions of the smallest gear, the largest gear turns one revolution, or for every one revolution of the smallest gear, the largest gear turns 0.31 (1/3.23) revolution, a total reduction of about 1:3.23 (Gear Reduction Ratio (GRR) = 1/Gear Ratio (GR)).
Since the idler gear contacts directly both the smaller and the larger gear, it can be removed from the calculation, also giving a ratio of 42/13≈3.23. The idler gear serves to make both the drive gear and the driven gear rotate in the same direction, but confers no mechanical advantage.
Automobile drivetrains generally have two or more major areas where gearing is used. Gearing is employed in the transmission which contains a number of different sets of gears that can be changed to allow a wide range of vehicle speeds, and also in the differential, which contains the final drive to provide further speed reduction at the wheels. In addition, the differential contains further gearing that splits torque equally between the two wheels while permitting them to have different speeds when travelling in a curved path. The transmission and final drive might be separate and connected by a driveshaft or they might be combined into one unit called a transaxle. The gear ratios in transmission and final drive are important because different gear ratios will change the characteristics of a vehicle's performance.

A 2004 Corvette with a six-speed manual transmission has the following gear ratios in the transmission:

GearRatio1st gear2.97:12nd gear2.07:13rd gear1.43:14th gear1.00:15th gear0.84:16th gear0.56:1reverse3.38:1In 1st gear, the engine makes 2.97 revolutions for every revolution of the transmission’s output. In 4th gear, the gear ratio of 1:1 means that the engine and the transmission's output rotate at the same speed. 5th and 6th gears are known as overdrive gears, in which the output of the transmission is revolving faster than the engine's output.
The Corvette above has an axle ratio of 3.42:1, meaning that for every 3.42 revolutions of the transmission’s output, the wheels make one revolution. The differential ratio multiplies with the transmission ratio, so in 1st gear, the engine makes 10.16 revolutions for every revolution of the wheels.
The car’s tires can almost be thought of as a third type of gearing. This car is equipped with 295/35-18 tires, which have a circumference of 82.1 inches. This means that for every complete revolution of the wheel, the car travels 82.1 inches (209 cm). If the Corvette had larger tires, it would travel farther with each revolution of the wheel, which would be like a higher gear. If the car had smaller tires, it would be like a lower gear.
With the gear ratios of the transmission and differential, and the size of the tires, it becomes possible to calculate the speed of the car for a particular gear at a particular engine RPM
For example, it is possible to determine the distance the car will travel for one revolution of the engine by dividing the circumference of the tire by the combined gear ratio of the transmission and differential.

It is also possible to determine a car's speed from the engine speed by multiplying the circumference of the tire by the engine speed and dividing by the combined gear ratio.

GearDistance per engine revolutionSpeed per 1000 RPM1st gear8.1 in (210 mm)7.7 mph (12.4 km/h)2nd gear11.6 in (290 mm)11.0 mph (17.7 km/h)3rd gear16.8 in (430 mm)15.9 mph (25.6 km/h)4th gear24.0 in (610 mm)22.7 mph (36.5 km/h)5th gear28.6 in (730 mm)27.1 mph (43.6 km/h)6th gear42.9 in (1,090 mm)40.6 mph (65.3 km/h)

Close-ratio transmissions are generally offered in sports car, motorcycles, and especially in race vehicles, where the engine is tuned for maximum power in a narrow range of operating speeds, and the driver or rider can be expected to shift often to keep the engine in its power band
Factory 4-speed or 5-speed transmission ratios generally have a greater difference between gear ratios and tend to be effective for ordinary driving and moderate performance use. Wider gaps between ratios allow a higher 1st gear ratio for better manners in traffic, but cause engine speed to decrease more when shifting. Narrowing the gaps will increase acceleration at speed, and potentially improve top speed under certain conditions, but acceleration from a stopped position and operation in daily driving will suffer.
Range is the torque multiplication difference between 1st and 4th gears; wider-ratio gear-sets have more, typically between 2.8 and 3.2. This is the single most important determinant of low-speed acceleration from stopped.
Progression is the reduction or decay in the percentage drop in engine speed in the next gear, for example after shifting from 1st to 2nd gear. Most transmissions have some degree of progression in that the RPM drop on the 1-2 shift is larger than the RPM drop on the 2-3 shift, which is in turn larger than the RPM drop on the 3-4 shift. The progression may not be linear (continuously reduced) or done in proportionate stages for various reasons, including a special need for a gear to reach a specific speed or RPM for passing, racing and so on, or simply economic necessity that the parts were available.
Range and progression are not mutually exclusive, but each limits the number of options for the other. A wide range, which gives a strong torque multiplication in 1st gear for excellent manners in low-speed traffic, especially with a smaller motor, heavy vehicle, or numerically low axle ratio such as 2.50, means that the progression percentages must be high. The amount of engine speed, and therefore power, lost on each up-shift is greater than would be the case in a transmission with less range, but less power in 1st gear. A numerically low 1st gear, such as 2:1, reduces available torque in 1st gear, but allows more choices of progression.
There is no optimal choice of transmission gear ratios or a final drive ratio for best performance at all speeds, as gear ratios are compromises, and not necessarily better than the original ratios for certain purposes.
__________________
Racecar spelled backwards is Racecar, because Racecar.

No, no, no you are an IDIOT!
This is right!!


In machine design one often needs to incorporate a Power Transmission between an energy source and the desired output motion. Examples include elements include: gears, friction drives, timing belts, flat belts, levers, and screw drives.

The Power Transmission often includes a Gear Ratio or Mechanical Advantage. A Gear Ratio can increase the output torque or output speed of a mechanism, but not both. A classical example is the gears on a bicycle. One can use a low gear that allows one to pedal easily up hill, but with a lower bicycle speed. Conversely a high gear provides a higher bicycle speed, but more torque is required to turn the crank arm of the pedal. This tradeoff is fundamentally due to the law of energy conservation and is the key concept of Mechanical Advantage. With a given power source you can either achieve high velocity output or high force/torque output but not both.

Mechanical Advantage refers to an increase in torque or force that a mechanism achieves through a power transmission element. For rotary devices the term Gear Ratio is used to define the Mechanical Advantage. The term Mechanical Advantage is used to describe components that include translation. The analysis below shows how one calculates the Gear Ratio and Mechanical Advantage of a Power Transmission component.



The law of energy conservation dictates that one can never get more energy in the output motion than provided by the energy source. Indeed, one always has some energy loss in a Power Transmission. Energy loss rates can vary from 5% for a flat belt drive to up to 80% for a multi-stage gear transmission (higher and lower rates can occur too).

Before the analysis we first define some notation:

P => Power
E => Energy
W => Work
f => Force
t => torque
d => distance of translational motion
q => angle of rotational motion (in radians)
v => velocity of translational motion
w => angular speed (in radians per second)
d => change
Pd => Pitch diameter
n => number of teeth on a gear
nrev => number of revolutions


For basic analysis of Gear Ratios we initially neglect frictional losses, and then incorporate their effect separately. With this assumption we can set the power in to equal to the power out.

Pin = Pout

Power is defined as the change in energy divided by the change in time.

P = dE/dt

In a mechanism energy is transferred by mechanical work. For translational motion work is given by:

Work = Force X Motion (where the force and motion are parallel to each other)
W = f dd

The corresponding definition of work for rotational motion is given by:

Work = Torque X Rotary Motion
W = t dq

In a Power Transmission the Work is the source of the change in energy, and thus:

P = dE/dt = W/dt

Substituting the rotary definition of work into the above equation, and noting that rotation velocity is given by w=dq/dt, the power transfer in a rotary device is given by:

P = W/dt = t dq/dt
P = t w

In a similar fashion, for translational motion the power transfer is given by:

P = W/dt = f dd/dt



A gear train is shown below with an input gear on the left and an output gear on the right. For the purposes of this analysis we assume the input gear may is attached to a motor, and the output gear is attached to a shaft on a machine that performs a desired function.

As shown the input gear is rotating counterclockwise with an angular velocity of win and the output gear is rotating clockwise with an angular velocity of wout. An input torque, tin, is applied by the motor onto the input gear, and an opposing output torque, tout, is applied by the machine onto the output gear. The radius of the gears is shown at the Pitch Circle of the gear, which is between the top and bottom of the gear tooth, and represents the radius at which contact occurs between the two gears.

The development of gear shapes has been optimized significantly to reduce frictional losses, provide smooth power transfer, and reduce noise.
The shape of the gear teeth are the some on both the input and output gears, and thus the larger gear has more teeth on it. The Pitch distance, Pd, is the distance between gears. Thus the number of teeth on the gear, n, times the Pitch is equal to the circumference of the gear. Accordingly,

Pd nin = 2 p rin

Pd nout = 2 p rout

nin/ nout = rin/ rout

The gear pair is analyzed with the following assumptions:

• Quasi-static analysis (it is assumed that the gears are rotating at a constant speed, and thus acceleration torques can be neglected)
• Frictional losses are neglected (friction can be significant, and should be considered separately!)
• The gear teeth mesh with each other (no jumping of gears!)

Since there are no frictional losses, the input and output power can be set equal to each other as:

Pin = tin win

Pout = tout wout

tin win = tout wout

We now need to consider the relative velocity of the two gears, which is determined by the meshing of the teeth. Since the teeth mesh, we know that the same number of teeth must mesh from both gears. For each revolution of the input gear the following number of teeth pass through the mesh area, where nrevin is the number of revolutions of the input gear:

number of teeth that mesh = nrevin 2 p rin / Pd

Applying the same equation to the output gear, and setting the number of meshed teeth equal to each other provides:

nrevout 2 p rout / Pd = nrevin 2 p rin / Pd

The above equation simplifies to:

nrevout / nrevin = rin / rout

If we multiple the number of revolutions by 2p, we get the angle of rotation of both gears in radians, which gives:

rin dqin = rout dqout

If we divide the angle of rotation by time, dt, then we get the ratios of angular velocities in radians per second

wout/ win = rin / rout

An alternative interpretation is that the angular velocity at the mesh point is the same for both gears. Since velocity of a point on a rotating object is given by rw. The velocity equality at the mesh point is given by:

rin win = rout wout

And we see that the two previous equations are identical.

Since the radius of a gear is proportional to the number of teeth, the velocity relationship can be given in terms on numbers of teeth on the input and output gears. Simply substitute into the above equation that nPd=2pr for both gears, to give:

wout/ win = nin / nout

We can now combine the power equation with the velocity equation to get the ratio of input and output torques:

tin win = tout wout (power equation)

tout / tin = win / wout

tout / tin = rout / rin (substituting in velocity relationship)

Thus when the input gear is smaller than the output gear:

• The output torque is higher than the input torque
• The output velocity is lover than the input velocity (i.e. the smaller gear needs to make more revolutions than the larger gear)

The fundamental equations for a gear pair are:

tin win = tout wout (power equality)

wout/ win = rin / rout (velocity relationship in terms of radiuses)

wout/ win = nin / nout (velocity relationship in terms of number of teeth)

tout / tin = rout / rin (torque relationship in terms of radiuses)

tout / tin = nout / nin (torque relationship in terms of number of teeth)


The Gear Ratio is defined as the input speed relative to the output speed. It is typically written as:

Gear Ratio = win : wout

[Bobblehead]

This kind of reminds me of the time that CJ guy started talking to himself.

[Ultramaroon]

Originally Posted by Tcoat

No, no, no you are an IDIOT!
This is right!!


In machine design one often needs to incorporate a Power Transmission between an energy source and the desired output motion. Examples include elements include: gears, friction drives, timing belts, flat belts, levers, and screw drives.

The Power Transmission often includes a Gear Ratio or Mechanical Advantage. A Gear Ratio can increase the output torque or output speed of a mechanism, but not both. A classical example is the gears on a bicycle. One can use a low gear that allows one to pedal easily up hill, but with a lower bicycle speed. Conversely a high gear provides a higher bicycle speed, but more torque is required to turn the crank arm of the pedal. This tradeoff is fundamentally due to the law of energy conservation and is the key concept of Mechanical Advantage. With a given power source you can either achieve high velocity output or high force/torque output but not both.

Mechanical Advantage refers to an increase in torque or force that a mechanism achieves through a power transmission element. For rotary devices the term Gear Ratio is used to define the Mechanical Advantage. The term Mechanical Advantage is used to describe components that include translation. The analysis below shows how one calculates the Gear Ratio and Mechanical Advantage of a Power Transmission component.


The law of energy conservation dictates that one can never get more energy in the output motion than provided by the energy source. Indeed, one always has some energy loss in a Power Transmission. Energy loss rates can vary from 5% for a flat belt drive to up to 80% for a multi-stage gear transmission (higher and lower rates can occur too).

Before the analysis we first define some notation:

P => Power
E => Energy
W => Work
f => Force
t => torque
d => distance of translational motion
q => angle of rotational motion (in radians)
v => velocity of translational motion
w => angular speed (in radians per second)
d => change
Pd => Pitch diameter
n => number of teeth on a gear
nrev => number of revolutions


For basic analysis of Gear Ratios we initially neglect frictional losses, and then incorporate their effect separately. With this assumption we can set the power in to equal to the power out.

Pin = Pout

Power is defined as the change in energy divided by the change in time.

P = dE/dt

In a mechanism energy is transferred by mechanical work. For translational motion work is given by:

Work = Force X Motion (where the force and motion are parallel to each other)
W = f dd

The corresponding definition of work for rotational motion is given by:

Work = Torque X Rotary Motion
W = t dq

In a Power Transmission the Work is the source of the change in energy, and thus:

P = dE/dt = W/dt

Substituting the rotary definition of work into the above equation, and noting that rotation velocity is given by w=dq/dt, the power transfer in a rotary device is given by:

P = W/dt = t dq/dt
P = t w

In a similar fashion, for translational motion the power transfer is given by:

P = W/dt = f dd/dt


A gear train is shown below with an input gear on the left and an output gear on the right. For the purposes of this analysis we assume the input gear may is attached to a motor, and the output gear is attached to a shaft on a machine that performs a desired function.

As shown the input gear is rotating counterclockwise with an angular velocity of win and the output gear is rotating clockwise with an angular velocity of wout. An input torque, tin, is applied by the motor onto the input gear, and an opposing output torque, tout, is applied by the machine onto the output gear. The radius of the gears is shown at the Pitch Circle of the gear, which is between the top and bottom of the gear tooth, and represents the radius at which contact occurs between the two gears.

The development of gear shapes has been optimized significantly to reduce frictional losses, provide smooth power transfer, and reduce noise.
The shape of the gear teeth are the some on both the input and output gears, and thus the larger gear has more teeth on it. The Pitch distance, Pd, is the distance between gears. Thus the number of teeth on the gear, n, times the Pitch is equal to the circumference of the gear. Accordingly,

Pd nin = 2 p rin

Pd nout = 2 p rout

nin/ nout = rin/ rout

The gear pair is analyzed with the following assumptions:

• Quasi-static analysis (it is assumed that the gears are rotating at a constant speed, and thus acceleration torques can be neglected)
• Frictional losses are neglected (friction can be significant, and should be considered separately!)
• The gear teeth mesh with each other (no jumping of gears!)

Since there are no frictional losses, the input and output power can be set equal to each other as:

Pin = tin win

Pout = tout wout

tin win = tout wout

We now need to consider the relative velocity of the two gears, which is determined by the meshing of the teeth. Since the teeth mesh, we know that the same number of teeth must mesh from both gears. For each revolution of the input gear the following number of teeth pass through the mesh area, where nrevin is the number of revolutions of the input gear:

number of teeth that mesh = nrevin 2 p rin / Pd

Applying the same equation to the output gear, and setting the number of meshed teeth equal to each other provides:

nrevout 2 p rout / Pd = nrevin 2 p rin / Pd

The above equation simplifies to:

nrevout / nrevin = rin / rout

If we multiple the number of revolutions by 2p, we get the angle of rotation of both gears in radians, which gives:

rin dqin = rout dqout

If we divide the angle of rotation by time, dt, then we get the ratios of angular velocities in radians per second

wout/ win = rin / rout

An alternative interpretation is that the angular velocity at the mesh point is the same for both gears. Since velocity of a point on a rotating object is given by rw. The velocity equality at the mesh point is given by:

rin win = rout wout

And we see that the two previous equations are identical.

Since the radius of a gear is proportional to the number of teeth, the velocity relationship can be given in terms on numbers of teeth on the input and output gears. Simply substitute into the above equation that nPd=2pr for both gears, to give:

wout/ win = nin / nout

We can now combine the power equation with the velocity equation to get the ratio of input and output torques:

tin win = tout wout (power equation)

tout / tin = win / wout

tout / tin = rout / rin (substituting in velocity relationship)

Thus when the input gear is smaller than the output gear:

• The output torque is higher than the input torque
• The output velocity is lover than the input velocity (i.e. the smaller gear needs to make more revolutions than the larger gear)

The fundamental equations for a gear pair are:

tin win = tout wout (power equality)

wout/ win = rin / rout (velocity relationship in terms of radiuses)

wout/ win = nin / nout (velocity relationship in terms of number of teeth)

tout / tin = rout / rin (torque relationship in terms of radiuses)

tout / tin = nout / nin (torque relationship in terms of number of teeth)


The Gear Ratio is defined as the input speed relative to the output speed. It is typically written as:

Gear Ratio = win : wout

OP should have bought a prius.

[Ultramaroon]

Everybody wants to race me.

Everybody fucks with my car even when I'm parked out in the back 40.

<other model car> owners are all dooshbags.

[Tcoat]

Originally Posted by Ultramaroon

Everybody wants to race me.

Everybody fucks with my car even when I'm parked out in the back 40.

<other model car> owners are all dooshbags.

Good ones!!!!!!

[Koa]

@Tcoat LOL that gear explanation tidbit. so damn true. Where's @stugray at... I wanna hear his

[Bobblehead]

Originally Posted by Koa

@Tcoat LOL that gear explanation tidbit. so damn true. Where's @stugray at... I wanna hear his

All you have to do is mention how AWD has great traction from a dig, he'll come.

[Koa]

Originally Posted by Bobblehead

All you have to do is mention how AWD has great traction from a dig, he'll come.

he really is a damn smart guy with a thorough learning/knowledge-base to back it up, all things considered

[Tcoat]

Originally Posted by Bobblehead

All you have to do is mention how AWD has great traction from a dig, he'll come.

AWD...AWD...AWD

[Tcoat]

Originally Posted by Koa

@Tcoat LOL that gear explanation tidbit. so damn true. Where's @stugray at... I wanna hear his

I was thinking more the Ubersuber, Stonenewt, Wparsons (or Wbradley don't remember which and too lazy to go look so sorry one of you guys) debates really.

[Koa]

Originally Posted by Tcoat

I was thinking more the Ubersuber, Stonenewt, Wbradly debates really.

I figured, but stu has some great things to say about the shit 86 owners say, I guarantee that one ha

[Ultramaroon]

Originally Posted by Koa

@Tcoat LOL that gear explanation tidbit. so damn true. Where's @stugray at... I wanna hear his

I know! Right?

Originally Posted by Bobblehead

All you have to do is mention how AWD has great traction from a dig, he'll come.

lol

Originally Posted by Koa

he really is a damn smart guy with a thorough learning/knowledge-base to back it up, all things considered

Yeah, but that whole ebola catastrophuck...

[Bobblehead]

Originally Posted by Koa

he really is a damn smart guy with a thorough learning/knowledge-base to back it up, all things considered

He is and knows way more than I do. I just think he just got a little overzealous in that thread.

Originally Posted by Tcoat

AWD...AWD...AWD

You probably didn't think I'd get that reference, but I did. And a laughed for a solid minute.

[shellslinger]

Because race car