WOT Braking

[mechtech2]

HP and torque are directly related.
Just another way of measuring the same thing.

Online calculators provide decent HP estimates from your car's acceleration.
They work in reverse, for brakes!

One more thing, the torque converter can add substantially to the ultimate power out of the trans.

 

[OVERKILL]

Originally Posted By: mechtech2
HP and torque are directly related.
Just another way of measuring the same thing.

Online calculators provide decent HP estimates from your car's acceleration.
They work in reverse, for brakes!

One more thing, the torque converter can add substantially to the ultimate power out of the trans.


While they are directly related, they most certainly are not the same thing.

Torque the measurement of rotating force. Torque does not imply movement.

HP is the measurement of the rate at which work can be performed (work over time). You have to have movement to have HP.

A 300HP Diesel that makes 600lb-ft of torque is not the same as a 300HP V8 gasser that makes 350lb-ft of torque. Geared correctly, both can do the same amount of WORK in a given period of time, but given the same transmission and diff ratio, the engine with 600lb-ft of torque is going to be significantly more difficult to stop, as it is providing almost twice the rotational force to the wheels.

 

[Ben99GT]

Originally Posted By: Rix
If my cars couldn't take a failry regular flogging, I'd never own them.
(Toyotas of course)


So, I'm taking that to mean you don't own Toyotas?

 

[mechtech2]

When the brakes were applied, there was movement.
Therefore I used HP.

 

[OVERKILL]

Originally Posted By: mechtech2
When the brakes were applied, there was movement.
Therefore I used HP.


AND torque

Torque is simply not dependant upon movement. It can be applied whether movement occurs or not

 

[KrisZ]

How can brakes apply torque? I thought they applied linear force.

 

[Craig in Canada]

Originally Posted By: KrisZ
How can brakes apply torque? I thought they applied linear force.


Fred Flintstone's brakes are linear but ours aren't. In the case of discs, they provide a force (due to friction) at a distance (brake rotor radius) from the center of rotation (the hub). It is transferred to the ground by the wheels/tires, same as torque from the engine.

In terms of horsepower vs. torque. Horsepower is "torque at speed" (essentially plus modifiers depending on units of measure). An engine/motor capable of twisting 600ft-lbs at 10,000rpm is more "powerful" than one capable of twisting 600 ft-lbs at 5,000rpm because more work is being done. Make no mistake, though, the torque/twist is what moves you.

If you want to know how a car you're thinking of buying is going to drive look at the torque curves, not the peak HP rating.

 

[Rix]

Originally Posted By: Ben99GT
Originally Posted By: Rix
If my cars couldn't take a failry regular flogging, I'd never own them.
(Toyotas of course)


So, I'm taking that to mean you don't own Toyotas?

A bunch of toyotas, a datsun (inop) and an AMC (no engine).

The 7mge, 4age, and 22re that I drive on a normal basis get abused rather badly, and take it in stride. ESPECIALLY the 4age at 10,000 revs.

 

[jimvegas]

Originally Posted By: Rix

A bunch of toyotas, a datsun (inop) and an AMC (no engine).

The 7mge, 4age, and 22re that I drive on a normal basis get abused rather badly, and take it in stride. ESPECIALLY the 4age at 10,000 revs.