HP vs Torque!?!

[Frankthetank]

I know this is gonna sound like a retarded beginners question.....
But what is the difference between Horsepower and torque?

I understand torque, that it is the power to push ur car off the line, and its what gets you down the track.....

But what is the point of horsepower?

[2000pontiac6]

I always thought more torque = better off the line and hp like kept you going or something not exactly sure

[Tyler_LS1]

im not an expert at this, but find out what RPM your TQ drops off at.. and next time you go out and race your car, shift at that RPM and i bet you Quarter time will drop ALOT. genrally the faster your motor turns over then the more HP you have, TQ is just getting it to Turn over. its gives a nice lowend for driving on the street, but when your drag racing your mostly way up in the power band after the TQ drops off, idk if i expressed this the way i wanted to but hopefully this helps

2000pontiac6 is right about take off from the line ( if you take off from a lower RPM) you may get a better launch if you launch from you max TQ's RPM. ( considering you have the drive train to handle it)

[cailey37]

I know this is gonna sound like a retarded beginners question.....
But what is the difference between Horsepower and torque?

I understand torque, that it is the power to push ur car off the line, and its what gets you down the track.....

But what is the point of horsepower?

Torque is what you feel when you stab the throttle and plants you in your seat.......HP will translate into your MPH........

[Ed Blown Vert]

Torque is how quick you get to the line. HP is how fast you get to the line.

[Frankthetank]

lol what u mean ed....
do u mean hp is the speed ur at when u get to the line?

[Pythias]

I think of it as horsepower is just another name for topend or high end torque. Horsepower is what keeps you going after your torque has mostly dropped off. For example my friend has a stock 94 Mustang Gt 5 speed. He raced an Acura RSX the other day, from a dig in my friend would WASTE him, because he has much more torque than the RSX, however from a 70mph roll he lost by half a car becaue the RSX has more horsepower and revs higher. Hope this helped some.

[chevyguy8413]

Ok in physical terms , think of torque as the force produced (how intense the combustion cycle is) and horsepower is the accumulative effect of these cycles as RPM increases. Torque is frequently thought to be a function of displacement, when, in fact, other factors weigh heavily, as well....they all relate to air flow into the engine/cylinder filling. Horsepower is an indication of how high on the RPM curve the torque values are being maintained. Torque is measured; horsepowr is calculated from the torque and rpm by the following: BHP = (RPM x Torque)/5252

[tonyjnjz]

wow those mustangs are slower than i thought.........my 03 rsx-s didnt have shit up top.....was stock besides an ingen intake

[Frankthetank]

ok....im sorry i don tknow if im being dumb or not....but can u simplify the horsepower equation for me a little.....lol i feel like a tard

[Pythias]

wow those mustangs are slower than i thought.........my 03 rsx-s didnt have shit up top.....was stock besides an ingen intake

Well maybe the kid had mods? I dunno. Also my friend had stock 302 gears, 30 in 1st 60 in second 90 in third and so on, so that was a factor.

[Raoul-Duke]

wow those mustangs are slower than i thought.........my 03 rsx-s didnt have shit up top.....was stock besides an ingen intake

didn't have shit up top??!!...hmm my buddy had a 03 rsx s type with..cai, header, exhaust, i-vtec, and hondata controler er some crap like that...dude that car wasss sickkk top end...i mean sick to where i mean hanging with my buds m6 ls1 with a lid from a 30 mph roll....that thing would rev to near 9k....but once my buds ls1 hit third he slowly pulled away....however from a dig it was garbage

[BlackLT1Z28]

HP=(torquexRPM)/5252

Torque is a measure of twist and is the amount of work an engine can do.
Horsepower is derived from torque (as from equation) and is a measure of how fast an engine can do that work.
If you look at a dyno sheet, you'll notice that at 5252 RPM's, horsepower and torque are equal to each other.
But having a high horsepower engine isn't neccesarily better than a high torque engine. And this is where gear ratios come in. Torque is multiplied by the gear ratios, but horsepower is not. Horsepower is a function of RPM, so when the gear ratio changes (shifting) the RPM's change also.
This is why high torque engines and high revving high horsepower engines can perform similarily on the streets.
Sure, making a crap-load of torque at a very high RPM would yield high horsepower output, but making huge amounts of torque at a high RPM as opposed to a low RPM are two different things. Making torque at a lower RPM is more useful than a higher one. But this is how cams increase engine performance. Cams can move the torque band of an engine by increasing the fill-rates of an engine to a higher RPM. Since torque is the amount of work that can be done, and the most power comes from large fill-rates of a cylinder, filling that cylinder more effieciently at a higher RPM can yield more power, but a loss of torque and power down low.
Sorry for the long post. Let's put it this way.
Torque is for burnouts and horsepower is for moving down the track.

[Frankthetank]

hmmm that explained allot!....lol allot still a little over my head though.

I was always told that HP sells cars and torque wins races though

Also are u saying with smaller gears (higher number) ur torque is gonna increase?

[BlackLT1Z28]

hmmm that explained allot!....lol allot still a little over my head though.

I was always told that HP sells cars and torque wins races though

Also are u saying with smaller gears (higher number) ur torque is gonna increase?

Yep. Why do you think people upgrade their rear-end gear ratios.
Say someone has an engine putting out 300 lb/ft of torque, and had a 3:1 first gear and a 2.73 final drive. Their output at the wheels in first would be a total of 2457 lb/ft (300x3x2.73). But now, they decide to install 4.10's. Their new output would be 3690 lb/ft (300x3x4.10). That's an increase of 1233 lb/ft of torque!
That's why cars with lower gears launch so much harder and have the advantage from a dig.

[chevyguy8413]

HP=(torquexRPM)/5252

Torque is a measure of twist and is the amount of work an engine can do.
Horsepower is derived from torque (as from equation) and is a measure of how fast an engine can do that work.
If you look at a dyno sheet, you'll notice that at 5252 RPM's, horsepower and torque are equal to each other.
But having a high horsepower engine isn't neccesarily better than a high torque engine. And this is where gear ratios come in. Torque is multiplied by the gear ratios, but horsepower is not. Horsepower is a function of RPM, so when the gear ratio changes (shifting) the RPM's change also.
This is why high torque engines and high revving high horsepower engines can perform similarily on the streets.
Sure, making a crap-load of torque at a very high RPM would yield high horsepower output, but making huge amounts of torque at a high RPM as opposed to a low RPM are two different things. Making torque at a lower RPM is more useful than a higher one. But this is how cams increase engine performance. Cams can move the torque band of an engine by increasing the fill-rates of an engine to a higher RPM. Since torque is the amount of work that can be done, and the most power comes from large fill-rates of a cylinder, filling that cylinder more effieciently at a higher RPM can yield more power, but a loss of torque and power down low.
Sorry for the long post. Let's put it this way.
Torque is for burnouts and horsepower is for moving down the track.

whew...that's a "brainful" of info thanx ..u really kno howto say it

[smokin_ls1]

Torque feels fast. Horsepower is fast.

[BlackLT1Z28]

whew...that's a "brainful" of info thanx ..u really kno howto say it

No problem. Eh, just some shit I've picked up over the few years that I've been into cars. Ask me what torque is 3 years ago, I would have stared at you with a blank look on my face. When you're really curious about something, you'll find a way to understand it and make good use out of it. For some reason, I really understand a lot of the underlying mechanics of these amazing machines. I couldn't build one to save my life, but I can tell you how it works (for the most part).

[shady milkman]

No problem. Eh, just some shit I've picked up over the few years that I've been into cars. Ask me what torque is 3 years ago, I would have stared at you with a blank look on my face. When you're really curious about something, you'll find a way to understand it and make good use out of it. For some reason, I really understand a lot of the underlying mechanics of these amazing machines. I couldn't build one to save my life, but I can tell you how it works (for the most part).

me too..we are a amazing breed :P not really gear heads but damn close.

[BlackLT1Z28]

Yeah, but I would love to have to opportunity to tear down an engine and put it back together. With enough time, I think I could do it. MY friend and I might tear some old ass 4 banger out of some junkyard car and tear into that first, just to see how everything goes. God, I love engines.