Can someone explain the relationship between torque and horsepower? I have friends that say it's all about torque....others say you need theHP to "lay down the law!!!" What do you say?

 

Here is a fairly thorough explaination:

http://vettenet.org/torquehp.html

Dave

 

Thanks Dave for that link...I read the article and found it to be very informative.....I guess the bottom line is the torque provides the "fun factor." Here's what he says when comparing the similar torque outputsof the L98 vs LT1...

"First, each car will push you back in the seat (the fun factor) with the same authority..."

Torque is what you "feel" in your seat when you step on it! But for ultimate speed he advocates horsepower!

"...horsepower makes a major difference in how fast a car can accelerate, in spite of what torque on your backside tells you :-). "

I guess I'm kinda partial to the "fun factor." I just love me lots and lots o' torque!!! I call it the Vrrrrrmmm factor! It can really be intimidating to other cars on the streets... and it makes your exhaust sound way cool!!!! he he he he!

 

i've always heard/thought low to mid range torque was better for accelaration, but this guy does a pretty good job of debunking this assuming he is all correct. so after reading that i can infer that the low end torque is really only better for towing a lot of weight and high end torque is better for accelaration in sports cars? and that the peak horsepower is what determines top speed? am i right, because i've always had questions about this also? great post and link to the write-up.

 

LTstewy, I'm not sure I would interpret it that way.....maybe I'm wrong but as I understand it torque benefits acceleration in direct proportion to your car's gearing. Quoting from the article Bruce says, "First of all, from a driver's perspective, torque, to use the vernacular, RULES :-). Any given car, in any given gear, will accelerate at a rate that *exactly* matches its torque curve."

Bruce goes on to say, "Torque is the only thing that a driver feels, and horsepower is just sort of an esoteric measurement in that context. 300 foot pounds of torque will accelerate you just as hard at 2000 rpm as it would if you were making that torque at 4000 rpm in the same gear, yet, per the formula, the horsepower would be *double* at 4000 rpm. Therefore, horsepower isn't particularly meaningful from a driver's perspective, and the two numbers only get friendly at 5252 rpm, where horsepower and torque always come out the same."

Like I said, maybe I still don't have it right but from his explanation I gather that torque, in general, will help your car accelerate quickly.....but your car's gearing will ultimately determine how much use you'll be able to get out of it. But you appear to be right (if Bruce is correct) that it is peak HP @ RPM that determines top speed yet (to muddle things a bit) he also says that HP @ RPM also helps with acceleration on a drag strip....go figure!

I am very grateful that Bruce took the time to offer this very detailed and intricate explanation. His effort is much appreciated! However, I feel it would be beneficial for someone to now explain his explanation in terms the average driver can understand because apparently you and I are still somewhat unclear.

 

What it boils down to is that plenty of low-end torque is more useful on the street, stoplight-to-stoplight and daily driving. If you've ever driven a rotary engine-powered vehicle, you'd know what the opposite of torque is. Fortunately for the rotory engine owner, there is no vibration, so winding the thing out to 8000 rpm is actually fun! However, sudden bursts of speed, those that are so much fun on the street, are not really possible with a low-torque, small volumetric-sized engine-equipped vehicle.

On the street, torque rules!

 

Now you're torquing.....I mean talking!

 

Here is the best quiote I ever heard, from some I-forget-who GM executive years ago: "People shop for horsepower but they want torque."

 

Torque

 

I like this guide, it gives some good examples of why bothhp (the relationship between speed and torque) and torque are important.

http://www.houseofthud.com/cartech/t...horsepower.htm [sm=gears.gif]