[jp23rockstar]

Why is that the Camaro with 335hp and lighter than a 335i accelerate slower? Is GM not advertising the numbers correctly? This car with the HP and weight should be below the 5 second mark to 60mph.

[chain777]

The simple answer is torque, low-end torque in particular. Also, BMW tends to under promise and over deliver when it comes to performance stats.

[quikag]

Yeah power under the curve will likely favor the turbo inline six of a newer BMW over the 3.6L V6 in the Camaro. That said, the new Camaro V6 and 8-speed auto is a potent combination, so it'll be a lot closer than most BMW guys you'll run up against will think, so you might be able to surprise them:

[mjw930]

Exactly, you don't accelerate with HP, it's all about the torque curve. At the rear wheels the 335i puts down ~295 ft-lbs. The V6 Camaro is ~225 ft-lbs and it comes on about 500 rpm higher than the BMW.

[Ant_ss]

As stated by motortrend in a few head2head episodes, the 335i is making more power than BMW says...

[vtirocz]

Originally Posted by mjw930

Exactly, you don't accelerate with HP, it's all about the torque curve. At the rear wheels the 335i puts down ~295 ft-lbs. The V6 Camaro is ~225 ft-lbs and it comes on about 500 rpm higher than the BMW.

I get what you are trying to say, but power (rate at which work is done) under the curve IS what matters. You do accelerate with power. This may sound like semantics, but torque alone without knowing the rate at which it's done is meaningless.

[cellsafemode]

Both are needed for a decent picture. Torque accelerates you, it's literally the force that is moving your tires. How much it accelerates you is hp. more or less. Both are important to know when judging performance. Since you have gears that are changing while accelerating and hp alone wont shed light on what that means for acceleration and the same is true for torque. Put both together and you get a clearer picture on how the vehicle is performing.

[vtirocz]

Originally Posted by cellsafemode

Both are needed for a decent picture. Torque accelerates you, it's literally the force that is moving your tires. How much it accelerates you is hp. more or less. Both are important to know when judging performance. Since you have gears that are changing while accelerating and hp alone wont shed light on what that means for acceleration and the same is true for torque. Put both together and you get a clearer picture on how the vehicle is performing.

When judging performance, all you need to look at is the power vs. engine speed curve (this already takes into account torque). Power accelerates you. When people say they want good low end torque, they really mean they want good power at low engine speeds.

[cellsafemode]

Originally Posted by vtirocz

When judging performance, all you need to look at is the power vs. engine speed curve (this already takes into account torque). Power accelerates you. When people say they want good low end torque, they really mean they want good power at low engine speeds.

The phrase 'power accelerates you' as being more correct than ' torque accelerates you' is what is misleading. Power is not a force. It doesn't do anything by its definition. It is a calculated measure of energy expended over time to create the torque that is moving the wheels. 'Work accelerates you' would also make sense.

in any case, the argument is semantics.

[mjw930]

Ok, enough with the semantics. I said torque curve and in this example both curves are pretty close with the exception that the turbo motor achieves higher absolute torque starting at a lower RPM. With proper gearing the BMW will out accelerate the V6 Camaro which is why using the peak HP number as a reference is deceiving.

To satisfy the semantics discussion the BMW is making more HP at lower RPM's

[Marty McFlew]

Add an twin turbo to the 3.6 and we are in the 400tq and hp range easily. Caddilac has proven that.

[Number 3]

Just keep in mind a diesel will make far more torque than an equivalent displacement gasoline engine. Doesn't make it faster. HP is torque delivered over time. So a high HP number only matters to an extent.

[SuperSound]

The N55 (in the current gen) dynos anywhere from 275-300rwhp. That's your answer. Hell my 328i (N20) is rated at 240hp and I've seen dynos with 240rwhp. BMW doesn't SAE rate so they put whatever they feel like on their engines.

[doc7000]

You need to look at torque and rpm, horsepower is a way to look at both at a glance without having to think about it.

The best answer that I got is the rating on European turbocharged motors essentially requires them to get heat soaked before they are tested.

With that being said there are also other factors involved in why the numbers are what they are, however there should be some performance context. Car and Driver not that long ago tested a V-6 Camaro with a 6 speed manual gear box, it weighed 3,469 pounds (http://www.caranddriver.com/reviews/...-6-test-review). They ran from 0-60 in 5.1 seconds Car and Driver also tested a BMW 340 (the new 3.0T engine rated at 320BHP) and a manual transmission and it ran from 0-60 in 4.8 seconds while weighing a heft 3,686 pounds. The difference in power really pays off at higher speeds as the BMW gets to 150MPH well before the Camaro got to 140MPH. This just comes down to the BMW making a good deal more power and offering a healthy curve.

It is also important to note that these two test were not the same day, driver, location though I wouldn't expect the places to reverse. The 200 pounds difference in weight is more then offset by the near 50ft-lbs difference in torque (presumptuously that close when heat soak has kicked in) carries the day. Maybe when the V-6 1LE comes out we will have these two cars performing closer then they are now.