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That’s the funniest thing I’ve seen… first it was crap for being a turbo car and now it’s bad attribute is the lack of? F’ing idiots the media and YouTube’ers are.
It’s funny, yes, but they’re comparing a turbo-6 cylinder that makes 444hp/410lb-ft torque to the Porsche 4.0.

But as I’ve said earlier in the thread, the turbo 2.5L does make more low end torque than the 4.0. That BMW 6 makes 90 lbft more than either motor.
 

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It’s funny, yes, but they’re comparing a turbo-6 cylinder that makes 444hp/410lb-ft torque to the Porsche 4.0.

But as I’ve said earlier in the thread, the turbo 2.5L does make more low end torque than the 4.0. That BMW 6 makes 90 lbft more than either motor.
Agreed, the torque on the BMW is in a different league to both Porsche engines, which I think is what they are getting at (i.e. it doesn't matter which way you cut it the BMW has more torque than and 718 Cayman GTS ). Torque isn't everything though - i'd still rather have the GTS 4.0 an d it would appear it was their first choice as well.
 

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Agreed, the torque on the BMW is in a different league to both Porsche engines, which I think is what they are getting at (i.e. it doesn't matter which way you cut it the BMW has more torque than and 718 Cayman GTS ). Torque isn't everything though - i'd still rather have the GTS 4.0 an d it would appear it was their first choice as well.
Yes, just like sound isn't everything if torque matters..
 

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Gentlemen, don't forget the basic physics. Torque at the wheels is what accelerates the car forward. You can get any torque at the wheels you want by gearing down. But gearing down means going slower. The trick is to get torque at higher speeds. That requires power. So the key question is, and presumably the reviewers know this, which car has more torque at any given speed? Once you've established that, the acceleration is that torque driving the mass, which means both the linear mass of the car and the rotational mass of the flywheel, gears, wheels, etc. The bottom line such as you'd feel in your bottom is the acceleration for any given speed.
 

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Gentlemen, don't forget the basic physics. Torque at the wheels is what accelerates the car forward. You can get any torque at the wheels you want by gearing down. But gearing down means going slower. The trick is to get torque at higher speeds. That requires power. So the key question is, and presumably the reviewers know this, which car has more torque at any given speed? Once you've established that, the acceleration is that torque driving the mass, which means both the linear mass of the car and the rotational mass of the flywheel, gears, wheels, etc. The bottom line such as you'd feel in your bottom is the acceleration for any given speed.
Agree 100% with this.
 

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So if physics comes into this, I have to point out that the performance car industry does not correctly understand what torque is:

Power = Torque X RPM X Constant

So if two engines (of any technology) produce the same power at the same RPM, they are also producing the same torque (at that RPM).

The thing is that most engines produce max torque lower in the rev range and it then drops as RPM goes up. This is particularly the case on a turbo where max torque is typically at the lowest RPM the turbo achieves full boost, and then the torque drops off once the turbo flows more than it can do efficiently (upper mid range).

So in the performance car industry, the word torque has been used to describe power at low RPM. That is all it is. No need to use the word torque.There are some very rare engines (high revving NA engines like Honda S2000) which can produce a flat torque curve to very high RPM which results in a nice linear power curve (straight line with no humps until close to redline). I've never seen a turbo engine with a flat torque curve unless specific tuning was done with boost to achieve that... and that means intentionally reducing mid range power which is rarely desirable except for the case of striving for a flat torque curve.

So in comparing the M2 to the 718 4.0, you are taking two different engines. One has a big bump of torque at low RPM that trails off rapidly at high RPM. The other has a relatively much flatter torque curve that is not very high at low RPM but retains it at high RPM.

What human beings tend to feel as fast in a car is change in acceleration. If you take an old school turbo car with heaps of lag where the power comes in suddenly as boost hits, most people would find it feels faster than a NA car that is actually quicker as constant acceleration does not feel as frantic. The BMW can go from no acceleration to a large hit of acceleration in the mid range so it feels quick. The 718 4.0L does no have that initial hit, but build up with RPM... so it will never feel as quick even if it is.

Of course gearing comes into it... you can always get more torque and power by selecting a shorter gear... but nobody does that in dailt driving around town. It does work at the race track of course.

That is why I love the 718 2.5T. It is my first Porsche, and it is the reason I went Porsche. I have tuned many cars in my time, and I always got much more satisfaction out of turbo cars. The 718 made a Porsche turbo within my finacial means. And it has delivered in performance (mine is tuned for around 420hp). I would not have been happy with the performance of the NA 6 myself... but if I could have mine sound like the NA6 I would take that... just not without the performance of the 2.5T.
 

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So if physics comes into this, I have to point out that the performance car industry does not correctly understand what torque is:

Power = Torque X RPM X Constant

So if two engines (of any technology) produce the same power at the same RPM, they are also producing the same torque (at that RPM).

The thing is that most engines produce max torque lower in the rev range and it then drops as RPM goes up. This is particularly the case on a turbo where max torque is typically at the lowest RPM the turbo achieves full boost, and then the torque drops off once the turbo flows more than it can do efficiently (upper mid range).

So in the performance car industry, the word torque has been used to describe power at low RPM. That is all it is. No need to use the word torque.There are some very rare engines (high revving NA engines like Honda S2000) which can produce a flat torque curve to very high RPM which results in a nice linear power curve (straight line with no humps until close to redline). I've never seen a turbo engine with a flat torque curve unless specific tuning was done with boost to achieve that... and that means intentionally reducing mid range power which is rarely desirable except for the case of striving for a flat torque curve.

So in comparing the M2 to the 718 4.0, you are taking two different engines. One has a big bump of torque at low RPM that trails off rapidly at high RPM. The other has a relatively much flatter torque curve that is not very high at low RPM but retains it at high RPM.

What human beings tend to feel as fast in a car is change in acceleration. If you take an old school turbo car with heaps of lag where the power comes in suddenly as boost hits, most people would find it feels faster than a NA car that is actually quicker as constant acceleration does not feel as frantic. The BMW can go from no acceleration to a large hit of acceleration in the mid range so it feels quick. The 718 4.0L does no have that initial hit, but build up with RPM... so it will never feel as quick even if it is.

Of course gearing comes into it... you can always get more torque and power by selecting a shorter gear... but nobody does that in dailt driving around town. It does work at the race track of course.

That is why I love the 718 2.5T. It is my first Porsche, and it is the reason I went Porsche. I have tuned many cars in my time, and I always got much more satisfaction out of turbo cars. The 718 made a Porsche turbo within my finacial means. And it has delivered in performance (mine is tuned for around 420hp). I would not have been happy with the performance of the NA 6 myself... but if I could have mine sound like the NA6 I would take that... just not without the performance of the 2.5T.
Agree with much of what you’re saying here - feelable G forces (acceleration) are what people tend to prefer, all else being equal. Except I think torque is used by the automotive industry to refer to that feelable acceleration rather than power. Whereas power roughly translates to the ability to accelerate at high speeds/RPMs. The 2.5T generates “flat” torque in the middle of the RPM range and it does so instantly when the dynamic boost is spooled - see below. This results in an immediate jolt and hold of acceleration from as low as 3-4K RPM. This is what people describe as “low end torque.” What’s interesting to me is that Porsche, based on their own literature and the way the car sometimes behaves, tried to simulate linear torque buildup with the turbo by dumping boost when you apply slight throttle, which is actually kind of frustrating as it makes the car feel like a turbo car sometimes and an NA car other times.

32997
 

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So if physics comes into this, I have to point out that the performance car industry does not correctly understand what torque is:
Of course they do. They may not present it to the public correctly, marketing being all about swaying people's opinions. But any high school physics student who understands the basic course material knows what torque is. Engineers who design engines and the cars carrying them certainly know.
 

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So if physics comes into this, I have to point out that the performance car industry does not correctly understand what torque is:

Power = Torque X RPM X Constant

So if two engines (of any technology) produce the same power at the same RPM, they are also producing the same torque (at that RPM).

The thing is that most engines produce max torque lower in the rev range and it then drops as RPM goes up. This is particularly the case on a turbo where max torque is typically at the lowest RPM the turbo achieves full boost, and then the torque drops off once the turbo flows more than it can do efficiently (upper mid range).

So in the performance car industry, the word torque has been used to describe power at low RPM. That is all it is. No need to use the word torque.There are some very rare engines (high revving NA engines like Honda S2000) which can produce a flat torque curve to very high RPM which results in a nice linear power curve (straight line with no humps until close to redline). I've never seen a turbo engine with a flat torque curve unless specific tuning was done with boost to achieve that... and that means intentionally reducing mid range power which is rarely desirable except for the case of striving for a flat torque curve.

So in comparing the M2 to the 718 4.0, you are taking two different engines. One has a big bump of torque at low RPM that trails off rapidly at high RPM. The other has a relatively much flatter torque curve that is not very high at low RPM but retains it at high RPM.

What human beings tend to feel as fast in a car is change in acceleration. If you take an old school turbo car with heaps of lag where the power comes in suddenly as boost hits, most people would find it feels faster than a NA car that is actually quicker as constant acceleration does not feel as frantic. The BMW can go from no acceleration to a large hit of acceleration in the mid range so it feels quick. The 718 4.0L does no have that initial hit, but build up with RPM... so it will never feel as quick even if it is.

Of course gearing comes into it... you can always get more torque and power by selecting a shorter gear... but nobody does that in dailt driving around town. It does work at the race track of course.

That is why I love the 718 2.5T. It is my first Porsche, and it is the reason I went Porsche. I have tuned many cars in my time, and I always got much more satisfaction out of turbo cars. The 718 made a Porsche turbo within my finacial means. And it has delivered in performance (mine is tuned for around 420hp). I would not have been happy with the performance of the NA 6 myself... but if I could have mine sound like the NA6 I would take that... just not without the performance of the 2.5T.
Suggesting that the performance car industry does not understand what torque is, is a bold claim to make.

What constant would use in your stated formula? I've always understood the formula to be:

Power = Torque x RPM / 5252*
*this being the Constant

I do agree that many people find a turbo engine car "feels" faster than a NA car that is actually quicker, and would suggest that a comparison of the 718 GTS 2.5T and the 718 GTS 4.0 supports this statement.
 

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And it's pointless. People are different and buy cars for their own reasons. Nobody's reason is 'better' or 'more correct' than another person's. Likewise, there is no possible way to establish which of these cars is 'better', because 'better' is in the eye of the beholder.
 

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I should clarify what I meant with my claim about the performance industry not understanding what torque is.... I meant the media who review these cars... not the engineers who design them. Apologies for not being clear on that and any offense I may have made. The media use the word torque to refer to low end power. If an engine was to be reviewed that had high torque at high RPM (meaning very high power) but very low torque at low RPM, they would say it had not much torque even though it had good torque. The media interpret the torque number of an engine as low down power. And most of the time it is. But on certain engines that rev to high RPM, the peak torque may be at quite high RPM, and then the torque number does not represent its low end power. For instance, a Honda S2000 typically reaches max torque on the more aggressive VTech cam at >6000RPM. Some high revving Porsches (GT3) are similar.

I've worked on hundreds of tuned cars including dynoing them. Some were fast evidenced by great ET results but felt mundane. Some were not that fast but felt crazy fast. The ones that feel fast have a high positive gradient on a dyno curve (for power or torque). Typically they have not much power/torque at low RPM, and then something in the engine changes (boost of a turbo or Vtech cam etc.) that increases the power suddenly making a large positive gradient on the dyno curve. The engine may not even get to very high power after the sudden change. But it is these engines that always feel fast. The human body seems to interpret change in acceleration (acceleration of acceleration!!) as an indicator of how fast a vehicle is. A 747 at full thrust for takeoff will leave most cars behind over the quarter mile. But a manual transmission big turbo 4 cyclinder will feel faster even if it is slower.
 

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What constant would use in your stated formula? I've always understood the formula to be:

Power = Torque x RPM / 5252*
*this being the Constant
Correct for English units of (ft, lbs, horsepower). The constant is really just a unit conversion factor so the actual number depends on what units system you are using. By definition 1 hp = 550 ft-lbs/sec. Multiply 1/550 by 2 pi and divide by 60, since rpm is defined as revolutions per minute instead of linear ft/sec, and you get 1/5252. Of course if you used different units such as MKS (watts, meters, newtons, seconds), the number would be just 2 pi / 60 since scientific unit systems are defined to have conversion factors of 1. By convention in the US at least we express car engines in hp, torque in lb-ft.
 
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I was a little puzzled when I found my 2019 Cayman GTS. Prior owner had spec’d it with alcantara deleted from everything and replaced with leather and carbon fiber. Not complaining about the leather but I kind of like the look of alcantara - why do people dislike it?
Not to derail, but I did the same as your fellow. GTS 4.0 w/ full leather to remove the race-tex/suede/Alcantara. Then I added back the carbon fiber trim.

I have black/beige combo, so carbon fiber trim is a great transition material, IMO.

I don't like the vacuum cleaner like trails the suede look can leave when you brush it, leaving butt-prints and arm swipes. Also, I'm in Texas and demand ventilated seats: only w/ leather pkg. I wanted a light and airy feel inside: so many dark interiors in cars. The beige seats and doors feel nice and sunny.

The black suede does look nice on the A-pillars and Cayman roof. You almost never ever touch that so it should always have a nice textured appearance.
 
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Was and still am seriously tempted by the Spyder. Probably could live with the archaic roof mechanism (how bad could it be compared to my Alpine?) and the goofy interior door release straps. Regardless, I'm in the same camp as @Graustark in that race-tex/suede/Alcantara isn't for me and ventilated seats (not a Spyder option) are absolutely required in this part of Texas. Thus, GTS it is.
 

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Suggesting that the performance car industry does not understand what torque is, is a bold claim to make.

What constant would use in your stated formula? I've always understood the formula to be:

Power = Torque x RPM / 5252*
*this being the Constant ..... snip.............
Actually it is not a bold claim to make. All you need for proof is a little education in physics followed by reading most any automotive magazine.

The reason for the earlier poster putting a "constant" in the hp formula is because the world of physics has several kinds of horse power, In America we typically measure things like horse power using units like feet and pounds while most of the rest of the world uses units like kilograms and meters. So that situation requires two different constants even if the two systems were otherwise equal, which they are not. "Our" hp is defined as 550 foot pounds per second while the other guys claim one hp converts to 542.48 foot pounds per second. And now we have "electrical" hp which is taken to be 746 Watts. So these things are pretty close to equal, but not exactly equal. Therefore, the constants in the formula would be different.

Furthermore when "those guys" are talking about cars, they typically measure DIN hp of an engine as installed while "we" measure the engine output without accessories. That's a bit over simplified, but you get the idea. So even though the two (or now three) basic hp types are pretty close, when it comes to rating the power a car engine produces, the difference is larger because of the way it's actually measured.

If this isn't complicated enough, consider "Tax hp", something especially loved by the French which is why the Citroen 2CV is rated at 2 hp. But not regular hp. The name of the car is actually Citroen deux chevaux-vapeur , which means it is taxed at two "steam" horsepower.

But "those guys" didn't give up making things even more confusing. For a while now the EU has demanded that a car's power be stated in KW's rather than hp.

Bottom line: Horse power is kind of complicated, but the point made by the earlier poster is that many people (including many professionals in the motoring sports business) erroneously think that horse power is one thing and torque is another thing entirely.
 

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^Good points.

Horsepower calculation isn't complicated. The equation is straight forward (vosadrian, post 86 above): power = torque * rotational speed * constant

'constant' can be in the numerator or denominator, it doesn't matter as long as the correct constant is used. Most commonly, people are used to seeing constant as 1/5252 (0.0001904), but that number is only good for specific units of measure of torque (ft-lbs) and rotational speed (rpm). And so the fight starts when people don't understand that (system of units) and use the wrong units or wrong constant, or are misled by manufacturer's slight of hand, etc.

The key in application is that power is proportional to torque * rotational speed.

Every engine (including the NA Flat 6 or Turbo Flat 4) varies in its ability to produce torque as a function of rotating speed (the 'torque curve'), good or bad depending on mechanics and electronics of the engine. And the manufacturer can amplify good or bad aspects of that torque curve with the gear ratios.

I'm personally a fan of good torque at low rotational speed. I suspect Porsche has done a good job with the NA Flat 6. I know they have with the Turbo Flat 4.
:)
 

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A lot of great info on this thread, especially the latest posts.

It occurred to me that nobody, be it here or any journalist for that matter, hasn't touched on a denominator that is often talked about when it comes to the 4 vs. 6 topic.

Hope I am not, nor is it my intention to stoke any flames so be kind!

Thinking back to when the B entry luxury sedan market was truly taking off with the likes of the A4, C class and 3 series bringing out more and more permutations. This was while I was still living in Canada and the 3 and C were mostly 6 cylinders while the bread and butter A4 stuck with a 1.8T and soon after the 2.0T. I had a string of Audi A4s and always with the 4 cyl. I'd test drive the competition each time a switch was to be made but always came back to Audi. Mostly due to brand loyalty.

However, I did always find that the C class felt more premium, complete and in general more substantial. I realised it came down to that lump of a V6 purred away quietly and didn't have to work so hard. I then took an S4 for a drive and confirmed my suspicions. Yes, the S4 was exceptionally faster than the A4 I ended up ordering but as mentioned above, the 6 cyl did provide a more upscale and premium experience.

Having thought through the above again, I called up a mate who has a 996 Carrera and asked we take his car to see my OPC about my next car. He's driven mine a few times, 2.5 GTS, and commented how much faster, nimble etc it is compared to his. He loves it as do I. However, sitting in his car, feeling the weight of that engine and all that comes with it did heighten the experience. By no means did it make it a better car but it did touch on the points mentioned above.

Would be interesting to hear from those who have had both a 4 cyl and now a 6 718 and whether or not any of the above is ringing true.

Flipping that on it's side, the day that my GTS 2.5 is going back to my OPC is drawing closer and while I am ecstatic to be getting a Spyder I am feeling the pangs of sellers remorse. I've only had this car for a short while but what a car. Going back to the sound, I personally love it. Throaty, long legs etc. Perhaps I'm reading more forum posts than I should but all the threads about long gearing, loss of pops/bangs etc has me looking at the GTS with more appreciation and dare I say admiration.

Apologies for the wavering reply. :unsure:
 
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