Dont understand (Horsepower vs Torque)
 

Hi

I thought horsepower was what gave a car torque,..so how come I see this:

The standard Genesis engine is a direct-injected 3.8-liter V6 that produces 333 horsepower and 291 lb-ft of torque.

Nissan z 332 horsepower and 270 lb-ft of torque

Can someone give me a simple explanation of why two engines have the same horsepower and different torque?

Horsepower is a product of torque and rotational speed (RPM). So if the engines have different torque curves the horsepower could be different. The equation is: HP = Torque x RPM ÷ 5252

So the genesis makes higher torque at lower RPM compared to the Z.

Torque is what you feel when you accelerate it's what pushes you back in your seat.

Short answer, its how the heads are designed and how the manufacturer wants the power curve to be also combined with the bore and stroke and compression. (since they're both NA) if you were comparing numbers between NA and FI I would have a different answer. What bluenoser said is the math part of the answer

I would also look at where the peak power is and what they rev to. I would be curious to see a Dyno sheet from the genesis. I don't wanna get into a debate over numbers but comparing those vehicles is gonna come down to how it drives. Seems to me Hyundai tweaked whatever they could to make it even more competitive on paper to gain more interest in the model since its comparitively priced to the 370

That might not explain it very well actually. The HP is actually a peak HP that only happens at one particular RPM. So the genesis and Z can make the same HP but at different RPMs. If you have a torque curve you can calculate what the HP curve is by that equation.

What Is Torque?

This one has a cool animated engine.

http://auto.howstuffworks.com/auto-p...tion/fpte4.htm

Just remember that there are multiple factors to bear in mind when comparing the relative speeds of two cars in terms of "my car is faster than yours". Weight, HP, and torque are your big 3 in a straight line.

To use your example:
stock nismo 370z 0-60: ~4.4 sec
quarter mile: 13 sec

stock hyundai genesis R-Spec: 0-60 ~4.7sec
quarter: 13.3

Listen to the guys above though they explained it better tbh.

genesis (and some 370) specs seem wayyyy off in this thread.

Hyundai Genesis Coupe - Wikipedia, the free encyclopedia

They don't have the same horsepower... Mystery solved!

Of course they are off it's wikipedia.

Larger engine and DI makes only 1hp more and 20tq more... Good job Hyundai?

Yup, pretty amazing, ha!

Not that it answers your question but a Genesis is not going to beat a Z even with more torque... read any review of the car... they are generally underwhelming.

Ok, New Hyundai Genesis Coupe 2013, 2.0T, 3.8, 3.8GT - Luxury Sports Car - Affordable Sports Car

It's target is the G37, not the Z. It's 300 lbs heavier.

good ol' magazine racing. ;)

I live my life one page at a time:icon17:

:bowrofl: :bowrofl: :bowrofl:

That one deserves some rep.

Until i reach that last page, i'm FREE!!!!

Hyundai is competing wherever there's a customer. Remember, They are 120lbs heavier than us. that's a small comparison compared to nearly 400lbs the G is... it seems like they are trying to get as close to Z performance as possible in a G-type body. and they are rapidly getting close to succeeding.

True story! I remembering reading a few months ago that their next model revision would put down 350hp which is a few over us then.

I hope it does so that Nissan has even more of a reason to step up their game. I love my car to death, but I also want to see it evolve.

I would have more respect if they made it 320hp or 340hp. Making it 333hp so that they can say we 1 up'ed (literally) the Z is tacky.

A lot of people say engine torque is what pushes you in the seat... That is true to an extent.

What really pushes you in the seat is wheel torque.. which is a product of gearing and horse power. Higher reving engines can use higher gear ratios which equate more wheel torque.

If you really want to be confused, think about this:

When you really boil it down an engine ONLY makes torque. Horsepower numbers are derived by simply applying a mathematical equation to the amount of torque made by the engine.

Typically, the higher in the rev range an engine makes its peak torque, the more peak HP it will make. That's why F1 engines put out 800+ HP but very little torque, because they can rev to 18,000 RPM.

Conversely, if an engine makes its peak torque lower in the rev range (think big, turbo diesel engines) it will have relatively low peak HP numbers, but much more torque. Lots of torque is needed when you need to pull heavy things like a trailer or a boat.

The ideal combination for a fun sports car is to have lots of torque AND lots of HP; usually achieved by some form of forced induction. Otherwise your basic gasoline engine typically falls into one of two categories:

1) A small to medium displacement engine that makes its peak torque higher up in the rev range. Think of the V6 in the 370Z as an example or even the V8 in a Ferrari 458. These engines need lots of revs to make power and are often described as having a "linear" power band. In other words, the more revs the engine turns, the more power it makes.

2) A large displacement engine that makes its peak torque lower in the rev range. Think of the 7.0L V8 in the Z06 or the 8.4L V10 in the Viper. These engines make tons of power (torque) right off idle and have very good throttle response. They might not make as much peak HP as say a 6.0L V12 that revs to 8,500 RPM, but they make much more power down low where most of us do the majority of our driving.

Typically, a high-HP, high-revving engine is more fun/useful on a racetrack and a high-torque engine is more fun on the street. The instant throttle response of a large displacement, high torque engine is what gives you that "pin you to the back of your seat" feeling when you step on the gas. The trade-off being that you usually (not always) don't have as many revs to play with as the smaller displacement, high HP engines do.

I hope that helps some and you're not completely confused by what I just wrote. :tup:

:icon18::tup:

Direct injection makes a difference for torque output.

For those 9 to 10 seconds I'm reading, the front cover, the pull out poster, the model interview, those things don't matter.