Winner: More Horsepower or More Torque

[mycivic]

It just occured to me. Who would win in a race from a stop? What about from a roll? Considering all other factors are the same. Both cars have the same drivetrain, weight, displacement, same driving skills for driver, everything is the same exept for hp and torque numbers.

A car with...

200 hp and 150 ft-pounds torque (max)

or a car with...

150 hp and 200 ft-pounds torque (max)

[ArideII]

I think it is important to know when the max torque is on tap and when the max hp is on tap. I would say that a car with 200trq on tap from the get go will pull from the line especially if the car with 200hp doesn't reach 200hp until 6-7k rpm's. I'm not sure about the role though.

[mycivic]

What about assuming that both peak out at a certain rpm both with hp and torque at the same time? Like say for example car 1 and car 2 peaks out at 7000rom for hp and 5500rpm for torque (just an example).

[Creagach]

according to Mr shelby, torque wins races

[Neutrino]

Ok as I psted this in numerous threads. ALL it matters is your torque curve over the RPM band. HP is just an arbitrary number derivative of that.

Horsepower = Torque* RPM/5252


here is all the info you need to answer your question:

http://vettenet.org/torquehp.html

[mycivic]

Thanks for the link. That answered my question alright.

[PunkAlex]

While horsepower is just a derivitive of torque, it is an accurate measurement for power. If hp didnt matter, then we would all be drivign 8 liter desiels that redline at 3000 rpms!

[Neutrino]

Originally Posted by mycivic

Thanks for the link. That answered my question alright.

No problem. Glad i could help.

Originally Posted by PunkAlex

While horsepower is just a derivitive of torque, it is an accurate measurement for power. If hp didnt matter, then we would all be drivign 8 liter desiels that redline at 3000 rpms!

you did not read my post or my link properly. HP is not a derivative of torque. Its a derivative of torque AND rpm.


The problem with diesels is that despite having huge torque, their torque curve tappers off very early on the rpm band. So you acccelerate hard but for a very short time.

On the other hand honda's in general have low torque and therefore cannot accelerate as hard. However due to vtec and its dual cam profile that torque curve its maintained across the rpm band for very long alowing you to accelerate for a long time.

And then comes gearing wich will take advatage of either powerband style.

[PunkAlex]

i know that hp is torque*rpm/5252. Thats why i made the desiel reference. Low end torque is nice, but having top end power is just as important for just about any type of racing. This is generally why you dont see 600 lb/ft torque desiels on a road racing course (just an analogy!)

Plus i was having problems wording that post....sorry about that!

[MexSiR]

The car with 200 hp would win if they reach it at 7000 in both cases.

[SiGNAL748]

what kind of car would have 150hp and 200lbs/ft though?

[Neutrino]

Originally Posted by SiGNAL748

what kind of car would have 150hp and 200lbs/ft though?

a diesel for one

[mycivic]

Well these questions were just out of curiosity. I know better now with the link Neutrino gave.

[MexSiR]

an old semi muscle car

[syr74]

Originally Posted by Neutrino

Ok as I psted this in numerous threads. ALL it matters is your torque curve over the RPM band. HP is just an arbitrary number derivative of that.

Horsepower = Torque* RPM/5252


here is all the info you need to answer your question:

http://vettenet.org/torquehp.html

Neutrino is 100 percent correct. To put it in simple terms: torque is an engines ability to work, hp is an engines ability to work over time. I understand the comparison, but to pick a winner between these two is impossible. Reason number one is that your "theoretical" car with the 150hp peak is actually making 210hp at 5500rpm if it has 200lb-ft tq at 5500rpm.

The best recipe for acceleration is a fat, flat torque band. Revvers are cool, and everyone appreciates an efficient engine. But torque and a cars ability to apply it are what create acceleration.