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Why do the brakes "freeze" the suspension?

I made a crude sketch illustrating the relevant points of the shown image. Brakes engaged: The center of gravity is above ground, the brakes "try" to slow down the car, the car itself "...
Martin's user avatar
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15 votes
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Why does brake pedal ever move

You are correct, the brake pedal should only move when any of the 4 or more slave cylinder pistons move (some vehicles may have multiple cylinders in a caliper). Once the pistons of the slave ...
HandyHowie's user avatar
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14 votes

What is torque steer?

Torque steer is where a front wheel drive car pulls to the left or right under hard acceleration. This is relatively common in older front wheel drive cars, but as it is negligible in low powered cars ...
Rory Alsop's user avatar
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10 votes

Why do the brakes "freeze" the suspension?

As it turns out the answer is very obvious and frankly quite simple. Consider a 1 meter long plank. Now if you lift up the right side of the plank by 10 cm (0.1 meter), the left side moves a bit to ...
user60481's user avatar
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10 votes
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Purpose of small forward-facing deflectors in front of rear wheels

These are called wheel flaps or sometimes wheel spats and on some cars you see them on the front wheels too. The purpose is just as you have noted, aerodynamics. The leading edge of the tires is a ...
jwh20's user avatar
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8 votes
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How to convert Amp Hours to CCA?

While you'd want to believe there's a relationship between CCA (or even CA) and AH, there really isn't a simple one. The reason you cannot just convert it over, even with a rule of thumb, is because ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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What is surface charge and how does it affect battery testing?

I have often heard this term as well, but have never known the technical reasons or the actual root cause of what is known as a "surface charge". To figure it out, I took a gander at a website called ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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Why does the impeller of a torque converter sit behind the turbine?

Looking at the design, you can see the input shaft of the transmission goes all the way through the torque converter and sits in the front part where the turbine is. The splined part at the input ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes

Work over time; humans versus automobiles

The engine creates those 390 Nm per rotation, and at peak flywheel torque (≈ 2000 RPM), it rotates about 33 times per second. Considering work over time, that results to some 110 horsepower. I ...
Zaid's user avatar
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5 votes

How to convert Amp Hours to CCA?

As Paulster2 suggested, CCA (cold cranking amps) and Amp-hours are not related. Trying to convert one into the other is like trying to convert miles per hour (MPH) into miles per gallon. While miles ...
tlhIngan's user avatar
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5 votes

Multiple Batteries Charging

When you put two batteries in parallel they will share the charge among themselves. For example, if you connect two batteries together, one fully charged and one dead the resultant combination gives ...
vini_i's user avatar
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5 votes

How would a car handle differently if it had independent brake controls, like a pedal bike?

So, this all gets down to physics - inertia primarily. following assumes braking to a wheel-lock When you brake heavily, front only, the rear will try to lift, this will reduce traction of course on ...
kyle_engineer's user avatar
5 votes

Why do electric motors produce peak torque instantly vs gasoline engines

To expand on @Autistic's answer… There is no need for a transmission with an electric vehicle (assuming that the speed and characteristics of the motor match the application – for applications where ...
dlu's user avatar
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5 votes
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Can car alternator be used to save fuel by using it as a regenerative system at the same time?

What you describe, in somewhat inaccurate general terms is something that is in place today in hybrid vehicle designs. The specifics you've presented have multiple technical problems, especially the ...
fred_dot_u's user avatar
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4 votes
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Triangular/Parallel four-link suspension system, how it works

The suspensions pictured are of the racing variety. They have small bushings in them making flexing difficult. This is probably why you have a difficult time with them. Racing suspensions are ...
vini_i's user avatar
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4 votes
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Does a dual-clutch transmission require synchronizer cones?

Yes DCT transmissions have synchroniser mechanisms just like manual transmissions and they work the same. As the shift fork and sleeve travel towards the gear to be engaged.. If there is a speed ...
Orb's user avatar
  • 5,067
4 votes

How to convert Amp Hours to CCA?

There is a rule of thumb doing the rounds AH * 7.25 = CCA, but this is not guaranteed as not all batteries are created equal.... And just to note, we here in Europe also use CCA as well - having ...
Solar Mike's user avatar
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4 votes
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Why does the wheel size affect the cars gearing?

The answer lies in the rpm conversion to ground travel. Any gearing in a motor vehicle is designed to provide sufficient torque to begin moving (with load, of course) and to keep the engine in the ...
fred_dot_u's user avatar
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4 votes
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Why do most cars have positive offset wheels from the factory?

Positive offset allows the steering axis to move toward the centerline of the tire. This dimension, the distance of the centerline of the tire to the steering axis, is called the scrub radius. A 0 or ...
Tim B's user avatar
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4 votes
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Oxygen sensor "clean air source"?

According to Auto Service World, oxygen sensors requiring reference air can get it in several ways: Some O2 sensors were designed with laser welded “waterproof” housings and thereby seal the ...
David Bailey's user avatar
4 votes

Confused as to how components are powered

If you think about it, the electricity is available at the wall socket, but technically, the power doesn't come from there. It is routed to the wall socket via wiring. A vehicle is no different. Power ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes
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How is fuel pressure maintained when the pump isn't running?

By the use of one way or non-return valves. Which is why most fuel systems have warnings about which components / pipes should be disconnected or not or the order when working on them - some are at ...
Solar Mike's user avatar
  • 34.6k
3 votes

How would a car handle differently if it had independent brake controls, like a pedal bike?

It would surely handle differently, and that's why this is also done, but automatically. There's a brake pressure distributor in your car that distributes pressure depending on different factors, eg. ...
Bart's user avatar
  • 2,954
3 votes

Multiple Batteries Charging

When you connect the batteries together in parallel you force all of the batteries to the same voltage – this causes the more charged batteries to discharge into the less charged batteries until they ...
dlu's user avatar
  • 14.5k
3 votes

How does a timing light detect the electricity in the plug wire?

Most timing lights have a magnetic pickup that will 'detect' current flowing through the spark plug wire. This triggers the strobe to flash. The signal is not amplified, it closes a switch. I do ...
rpmerf's user avatar
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3 votes
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Why do hybrids have the aesthetic wheel cover on the body?

The wheel covers, or fender skirts Wikipedia says they are commonly called, are fairings installed to reduce drag in the wheel wells and thus to increase range. According to the same Wikipedia article,...
dlu's user avatar
  • 14.5k
3 votes

Is it possible to have a manual transmission electric car?

It is possible but given that electric motor achieves maximum torque at zero RPM, it is usually not required. The maximum power is usually obtained at 50% of maximum RPM (max RPM is the RPM at which ...
juhist's user avatar
  • 14.6k
3 votes

Is it possible to have a manual transmission electric car?

Yes, a simple method to convert a car from petroleum to electric involves removal of the engine and mounting of the motor to the transmission with an adaptor plate. Manual transmissions are preferred ...
Spencer Joplin's user avatar
3 votes

Is it possible to have a manual transmission electric car?

Sure the flexible torque characteristics of the electric motors used for EVs mean that you do not need a gearbox .But the weight and cost of electric motors is a strong function of Torque .Street cars ...
Autistic's user avatar
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