Inside Line tests new Audi RS5

[2o6]

That's not engineering, that's 9th grade science. If you're any sort of automotive enthusiast IMO you should think that way as deeper understanding = deeper appreciation IMO.

Most only think in terms of engine torque unrelated to gearing, and you know this.

[Onslaught]

I have it on good authority that you two RX-8 owners don't know shit about your cars. 

We both just go along with the stuff people say about them. Kind of like how I go along with gay jokes with the Miata. Or that I put just as much oil in my RX-8 as I do gas.

[CALL_911]

Most only think in terms of engine torque unrelated to gearing, and you know this.

Most also throw around figures without knowing what they actually mean.

Besides, what good is an engine without a transmission? The figures for the car are more pertinent than for the engine itself. Engine torque figures are sort of in a vacuum, no?

[r0tor]

We both just go along with the stuff people say about them. Kind of like how I go along with gay jokes with the Miata. Or that I put just as much oil in my RX-8 as I do gas.

yea... i pull up to a gas station and they ask me what grade - I say 30 weight....

Today I had to write an e-mail to our companies environmental whackos who are hounding me to fill out a "carbon footprint" survey based on your driving back and forth to work... their car selection is 2, 4, 6, or 8 cylinder cars and no "other" 

[sportyaccordy]

C'mon, guys. You know better than to take my bait by now. MrH has it correct - I stated car not engine. This implies torque at the drive axle, not at the crank shaft. The RX8 has very short gearing. As compared to the equivalently powerful 7th gen Accord, the RX8 actually has a bit higher peak torque (note I only did the calcs for first gear):

1st gear ratio * diff ratio * engine peak torque = car peak torque:

RX8, 238 hp:
3.76:1 * 4.444:1 * 159 lb-ft = 2657 lb-ft

7th gen Accord V6, 240 hp:
2.56:1 * 4.43:1 * 212 lb-ft = 2404 lb-ft

Which is not surprising; both cars weigh about the same, have about the same power, and hence are pretty close in acceleration.

Strange then that the cars don't at all feel the same.

Here's a good example... the S2000 makes 240HP and 153lb-ft of torque. It's also relatively light. I drove one and a 6-6 Accord (not back to back, but close enough in time to compare)... I'm pretty sure the S2K was faster, but the Accord damn sure feels faster & is easier to drive. Little wind up motors like the RENESIS and F20C have no guts down low... peak torque definitely doesn't tell the whole story. With the Accord 6-6 I'm certain you could get the car rolling in 5th or 6th gear w/o much fuss. rotor, wanna give that a try in your RX-8

[SVT666]

yea... i pull up to a gas station and they ask me what grade - I say 30 weight....

Today I had to write an e-mail to our companies environmental whackos who are hounding me to fill out a "carbon footprint" survey based on your driving back and forth to work... their car selection is 2, 4, 6, or 8 cylinder cars and no "other" 

Since your car burns as much oil as what spilled out of the Exxon Valdez, you should just check them all.

[sportyaccordy]

yea... i pull up to a gas station and they ask me what grade - I say 30 weight....

Today I had to write an e-mail to our companies environmental whackos who are hounding me to fill out a "carbon footprint" survey based on your driving back and forth to work... their car selection is 2, 4, 6, or 8 cylinder cars and no "other" 

Really though, 3, 5, 7, 9 cylinder and rotary powered motors probably don't account for more than 2% of all cars on American roads. Can you blame them?

[GoCougs]

Most only think in terms of engine torque unrelated to gearing, and you know this.

Yes, I do, and that's why I baited to begin with. Want more torque? Just go steeper gearing. This is why torque is irrelevant, and the only thing that matters is power and how you put it to the street (gearing).

[Onslaught]

With the Accord 6-6 I'm certain you could get the car rolling in 5th or 6th gear w/o much fuss. rotor, wanna give that a try in your RX-8

Just for fun I will next time I'm out. Probably won't try 6th.

[Cobra93]

I suppose the only appropriate response to the direction this thread took remains 

[Onslaught]

It's 5 pages long. It's way past being important anymore. Anything over 4 is too long.

[MrH]

Strange then that the cars don't at all feel the same.

Here's a good example... the S2000 makes 240HP and 153lb-ft of torque. It's also relatively light. I drove one and a 6-6 Accord (not back to back, but close enough in time to compare)... I'm pretty sure the S2K was faster, but the Accord damn sure feels faster & is easier to drive. Little wind up motors like the RENESIS and F20C have no guts down low... peak torque definitely doesn't tell the whole story. With the Accord 6-6 I'm certain you could get the car rolling in 5th or 6th gear w/o much fuss. rotor, wanna give that a try in your RX-8

I throw a right back at you.  First, for the stupid argument of "wanna give [get the car rolling in 5th or 6th gear] a try in your RX-8"?  What the fuck kind of argument is that?  Who would ever want to do that?  That's like trying to rip on a 911, and saying, "let's see you drift one of those things in reverse with that stupid weight distribution ".

Second, I your claim the Accord felt faster, but the S2k actually was faster.  What do you feel what you say a car "feels" fast?  Acceleration.  Your butt tells you, "hey, you, you're getting pushed back into your chair."  You know what a car needs to do to be faster than another car?  Accelerate faster.  It's impossible for a car to "feel" faster and not be faster.

[SVT666]

It's impossible for a car to "feel" faster and not be faster.

Your turn...

There are a lot of factors to how a car can "feel" faster and not be.

[2o6]

Your turn...

There are a lot of factors to how a car can "feel" faster and not be.

Nope! Mr. Engineer said so, so your opinion and knowledge isn't valid.

[Eye of the Tiger]

The last 747 I rode in didn't feel very fast, bit I'll be damned if the TV screen thing didn't say we were doing over 500 mph.

[Tave]

How acceleration "feels" is a simple equation: m/s^2

True, a lot of factors go into how a car accelerates, and how it accelerates under different circumstances, but there is no mystery to the "seat of the pants"  test. It's just a measure of g-force.


That said, human beings do bring a lot of subjective, prejudicial, psychological baggage into any experience. But objectively speaking, a car that goes a longer distance in a shorter amount of time should feel faster than the car that travels a shorter distance in a longer amount of time. If it doesn't, it doesn't have anything to do with the car.

[SVT666]

How acceleration "feels" is a simple equation: m/s^2

True, a lot of factors go into how a car accelerates, and how it accelerates under different circumstances, but there is no mystery to the "seat of the pants"  test. It's just a measure of g-force.


That said, human beings do bring a lot of subjective, prejudicial, psychological baggage into any experience. But objectively speaking, a car that goes a longer distance in a shorter amount of time should feel faster than the car that travels a shorter distance in a longer amount of time. If it doesn't, it doesn't have anything to do with the car.

"Feel" is not a mathematical equation.  A car can feel faster by making more noise, revving higher, etc.  Having smaller windows can make a car feel faster too.  There's more to a car feeling faster then just g-force. 

[r0tor]

With the Accord 6-6 I'm certain you could get the car rolling in 5th or 6th gear w/o much fuss. rotor, wanna give that a try in your RX-8

I've done 3rd a few times and wondered why the car felt like it had 10hp before I realized I never put it back into 1st gear...

[Raza]

It's impossible for a car to "feel" faster and not be faster.

That's the dumbest thing I've ever heard.  I'm assuming you've never driven a fast luxury car.  There is much more to the sensation of speed than being pushed back into your seat.  Stick to engineering; you've separated yourself from being human, there's no point in speculating what it feels like to be one. 

[Raza]

How acceleration "feels" is a simple equation: m/s^2

True, a lot of factors go into how a car accelerates, and how it accelerates under different circumstances, but there is no mystery to the "seat of the pants"  test. It's just a measure of g-force.


That said, human beings do bring a lot of subjective, prejudicial, psychological baggage into any experience. But objectively speaking, a car that goes a longer distance in a shorter amount of time should feel faster than the car that travels a shorter distance in a longer amount of time. If it doesn't, it doesn't have anything to do with the car.

Again, I'm assuming you've never driven a fast luxury car.  These things pick up speed and you don't even notice it; sure, AMGs and the like make you feel it a bit more, but when you talk about the run-of-the-mill, 380+bhp, V8, 0-60 in just under 6 seconds types, there is a huge difference in the speed and acceleration against the sensation of speed. 

[Tave]

"Feel" is not a mathematical equation.  A car can feel faster by making more noise, revving higher, etc.  Having smaller windows can make a car feel faster too.  There's more to a car feeling faster then just g-force. 

"human beings do bring a lot of subjective, prejudicial, psychological baggage into any experience"


Those factors are going to vary widely from person to person, even between the same person on different drives. There's been certain time, for whatever psychological reason, that my Aveo felt very fast one day. But that doesn't mean we need to entertain the idea, "an Aveo feels faster than a Mustang."


In any event, Sporty was clearly talking about power/torque and not small windows.

[Tave]

Again, I'm assuming you've never driven a fast luxury car.

Then you're flat out wrong. I've driven several MBs, BMWs, and Audis. I don't agree with your conclusions at all. The composure of a car at speed has little to do with the g-force you feel in your gut under acceleration.

[Raza]

Then you're flat out wrong. I've driven several MBs, BMWs, and Audis. I don't agree with your conclusions at all. The composure of a car at speed has little to do with the g-force you feel in your gut under acceleration.

You're interpreting what I said incorrectly.  I meant that it feels slower under acceleration.  Fast luxury cars are the best example.  I'll take two I have intimate experience with for a bit of anecdotal experience.  My dad's LS460 is without a doubt faster than my mom's S500, but take the two out for a run back-to-back, and you'll be surprised that the S500 wasn't faster, because it feels and sounds so much more vigorous under acceleration. 

You're right in saying that feel of acceleration is mathematical, but that is only one component of how fast a car feels under acceleration (which, I admit, you did briefly discuss in your post).

[r0tor]

Everyone in my family thought the Grand Am GT they had was fast but really is was just because if you put the gas pedal half way down the the throttle was actually 100% open... there are amillion gimmicks that can deceive the human brain into thinking a car is faster then it really is.

[the Teuton]

I remember my brother's old Merkur felt fast as hell even at 40 mph. Maybe its lowness to the ground, its big windows, and the fact it had a turbo added to the effect.

[Onslaught]

My Miata "feels" faster then my RX-8 but when I look at the speedometer reality comes back. Or if I had a van next to me at the light and it pulled away from the miata.

[GoCougs]

Strange then that the cars don't at all feel the same.

Here's a good example... the S2000 makes 240HP and 153lb-ft of torque. It's also relatively light. I drove one and a 6-6 Accord (not back to back, but close enough in time to compare)... I'm pretty sure the S2K was faster, but the Accord damn sure feels faster & is easier to drive. Little wind up motors like the RENESIS and F20C have no guts down low... peak torque definitely doesn't tell the whole story. With the Accord 6-6 I'm certain you could get the car rolling in 5th or 6th gear w/o much fuss. rotor, wanna give that a try in your RX-8

But equations don't lie. Butt dyno issues likely arise at less-than-full-throttle driving; from differing throttle mapping, to non linearity of the torque curve (especially turbo cars), to engine smoothness (I can imagine a rotary's innate smoothness can be deceptively tame), to even intake/exhaust/engine sound.

I can virtually guarantee most people, even a lot of enthusiasts, would swear a 5.0 Fox body Mustang GT would feel much faster than the average V6 Camcord of today; the engine rumble, the exhaust sound, the action of clutch and manual shifter, the intake roar; but as we all know it is actually a bit slower.

[Raza]

I can virtually guarantee most people, even a lot of enthusiasts, would swear a 5.0 Fox body Mustang GT would feel much faster than the average V6 Camcord of today; the engine rumble, the exhaust sound, the action of clutch and manual shifter, the intake roar; but as we all know it is actually a bit slower.

I agree. 

[MrH]

"human beings do bring a lot of subjective, prejudicial, psychological baggage into any experience"


Those factors are going to vary widely from person to person, even between the same person on different drives. There's been certain time, for whatever psychological reason, that my Aveo felt very fast one day. But that doesn't mean we need to entertain the idea, "an Aveo feels faster than a Mustang."


In any event, Sporty was clearly talking about power/torque and not small windows.

Exactly.  I doubt he's talking about everything but the seat of the pants feeling.

[MrH]

"Feel" is not a mathematical equation.  A car can feel faster by making more noise, revving higher, etc.  Having smaller windows can make a car feel faster too.  There's more to a car feeling faster then just g-force. 

All of which should make the S2k feel faster than the Accord.  And he was specifically talking about how the extra torque of the Accord made it feel faster.  Explain that.