GregBBRD

Make this simple. What moves my car forward....torque or horsepower...or are they a measurement of the same thing, with an rpm correction factor?

Mike B

Damn, I guess I'm done posting

My point is horsepower is a nice number to brag about but torque really gets the job done. I do agree, you can't have one without the other.

Can I post again?

EspritS4s

Actually, Mark, your point below about more HP resulting in more Torque at the wheels isn't wrong, you just have a very very confusing and convoluted way of making your point. More engine torque at a given RPM equals more torque at the wheels. More engine torque at a given RPM also results in more HP.

EspritS4s

Exactly. Torque accelerates the car.

mark kibort

Sure!

Well, the entire point of the difference of HP and torque, is to show that engine torque is generally worthless without speed associated with it. its the shape of the torque or HP curve really, or as I like to say, HP-seconds. (time spent in the different HP ranges or if you prefer torque, its the torque ONLY found at the rear wheels! (multiplied at the gear boxy) that counts.

While this is true, my way of explaining it forces you to look at the engine speed too, or do the final calculation of rear wheel torque, through the gear box. HP does that for you, so you want to know what will be faster, between two similar HP cars, one with more torque than the other? better look at the shape of the useable HP range on the curve. much harder to do this with a set of torque curves and gear ratios.
With race cars ,you then can easily find out what your shift points can be without having to multiply things out. just look at the hp curve, the gear spacing and find the optimal range of power, which provides the most HP-seconds.

EspritS4s

"its the torque ONLY found at the rear wheels! (multiplied at the gear boxy) that counts"

Yup, absolutely!

mark kibort

That was brought up on the physics forum too. chicken or egg? they say its the force on the piston. or momentium. I say that is even started and caused by the combustion of gas and air. (potenial energy turning to kinetic energy)

yes, the force that moves the car forward, is found at the rear tires, after the gear box reductions. HP does determine what the forces will be at the rear of the car, meeting the road. after all, to determine the force you need the torque, RPM and the gear ratios, using HP can make it more simple, especially in comparisons.

EspritS4s

Fair enough, engine RPM must be considered to determine the force applied by the wheels. True.

Landseer

.....Meanwhile, somewhere far, far north, near the line of ever-frozen tundra, sits OP bmac, wringing his hands diabolically behind a control panel last used by Stephen Baldwin in the movie Sliver, contemplating / deciding which Rennlist button next to push....

F451

Yeah! Every torque / hp post over here is potentially one LESS pollution post in other, otherwise enjoyable, threads.

Hopefully the polluters will get so engrossed in this thread and they won't have time to **** in the other pool(s).

One can dream can't they?

THANKS SO MUCH FOR SETTING UP THIS THREAD!

EspritS4s

Ah man... you hurt my feelings Oh well, I'll get over it. Everyone loves a good political, I mean HP/Torque discussion every once in a while...

danglerb

Nah, horsepower and torque have nothing to do with going forward.

F451

Wasn't directed at you actually, but thank you for not pointing out that I've polluted this thread with my not-really about hp/torque post.

Now I've done it twice. Ok, I'm outta here.

James Bailey

My S and W 500 Magnum makes about 2,600 ft lbs when I pull the trigger...it holds five rounds so some 13,000 ft lbs in my hand Fortunately only for a brief moment ! James Watt is probably doing cartwheels in his grave....

EspritS4s