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Which to me explains the 4.4 vs. 4.3 zero to sixty times for the base vs. the "S" by Car & Driver Mag.
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I also found the Car and Driver test reports very persuasive. In the pre 718 models, the $10K price bump from base to S got you some reasonable real world performance difference, but not in the 718.

That being said, with the nearest dealer 7 hours round trip, I couldn't test drive them both before ordering, and I'd never fault anyone opting for a larger/more powerful engine in sports car, even if the times when you can really make use of the extra performance on public roads are far and few between.

My 718 is now doing winter duty, and the last thing I need on snowy winter roads is more torque. So always keep in mind how you are going to use your car.
 

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Would you say then that the torque shaping is meant for fuel economy, which of course is only relevant on public roads?
I'm sure that's a benefit in certain circumstances. But torque-shaping tuning has been in production since the late 1990s -- part of what made the 1.8T engine in that VW GTi that I mentioned previously so revolutionary was that it was one of the first turbo engines with a flat-low torque curve profile, fully applied and in production. (That same engine was used in the 1st-gen Audi TT.) Fuel economy wasn't an overriding design goal for those -- it was performance, coupled with negating the disadvantages of previous turbocharged production engines, including turbo lag and poor performance and driving characteristics at lower RPMs.

The inspiration for those flat-low turque curves came from large turbodiesel trucks, which can't rev to high RPMs to produce power or torque. They need that low down. They also don't need to go fast - which when you think about it, production cars don't really need, either. Quickness and power under 'normal operating conditions' -- i.e., driving on public roads, almost always below 80 MPH -- was the primary design goal. In the 718, it still is unless one gets to (arguably) GTS and (certainly) the GT4.
 

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Below 4,000, though, I can hardly tell the difference. At 6,000? Dear Lord, is there ever a difference.
This is opposite of what I was expecting. When I compared the 2.0 WRX and 2.5 STi the difference was more down low due to greater displacement having more intrinsic power before boost came on and more exhaust flow to get the turbo spinning quicker. With the 718s I'd expect the difference to be magnified by the 2.5's variable turbo spooling up quicker. The biggest reason I was gonna go with the S was for greater low end torque. Did you just save me a lot of money?
 

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@Lelandjt...I would be inclined to test both a base and an S in your altitude. My Subaru's had significantly less power in Colorado than when transferred to the Texas Hill Country, but that was in 1994. It is possible Breckenridge at 9,600' and Oakland at effectively sea level may be two very different power equations.
 

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This is opposite of what I was expecting. When I compared the 2.0 WRX and 2.5 STi the difference was more down low due to greater displacement having more intrinsic power before boost came on and more exhaust flow to get the turbo spinning quicker. With the 718s I'd expect the difference to be magnified by the 2.5's variable turbo spooling up quicker. The biggest reason I was gonna go with the S was for greater low end torque. Did you just save me a lot of money?
If you study the differences in engine specs between the 2.0 and the 2.5, you'll understand why the 'S' doesn't add much torque.

First, it's worth noting that both engines are basically the same. Each are 2/3 of a 992.1 (read: 911) motor.

Excepting small things such as manifold capacity, the 2.5 S engine really has only two major differences from the 2.0:
  • A larger bore (102mm vs 91mm)
  • The VTG turbo
One of the 'golden rules' of IC engine design is: A larger bore creates horsepower, and a longer stroke creates torque.
This is the biggest reason why the 2.5 doesn't have a large torque advantage. Both engines have the same stroke length.

Turbocharging's basic effect on an engine is largely dependent on the relationship between bore and stroke. That said, it generally creates horsepower more than it creates torque because of the nature of forced induction. (The same rules generally apply for superchargers, too.)
However, note that the VTG turbo's peak pressure is only about 12 psi, while the standard unit in the 2.0s is around 18 psi. Knowing this, the 2.0's turbo tends to kick in later than the 2.5's -- meaning the 2.5's turbo is probably spooling more often, but delivering less PSI when it is spooling. This 'mild' induction greatly favors horsepower creation over torque creation, particularly in relatively low-inertia engines such as ours.

Now you know. :)

Bottom line: In terms of power delivery, the 2.5l 'S' engine has a noticeable advantage over the 2.0 only over 5K RPMs and at speeds beyond 90-95 mph.
 

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@Lelandjt...I would be inclined to test both a base and an S in your altitude. My Subaru's had significantly less power in Colorado than when transferred to the Texas Hill Country, but that was in 1994. It is possible Breckenridge at 9,600' and Oakland at effectively sea level may be two very different power equations.
I've driven my 2.0 base all over Colorado, including across the Continental Divide southeast of Aspen and to the peak of Mt. Evans (FYI: the highest paved road in the Western Hemisphere) -- and on 91 octane fuel, to boot. During that trip, I was above 7,000 feet for nearly four straight days, and above 9,000 feet for hours at a time.

Power loss was minimal, and fuel economy was not affected tremendously. You can thank real-time ECU engine management for much of it. :)

Here's a link to my post about the trip, which includes proof (i.e., pictures!).
 

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I've driven my 2.0 base all over Colorado, including across the Continental Divide southeast of Aspen and to the peak of Mt. Evans (FYI: the highest paved road in the Western Hemisphere) -- and on 91 octane fuel, to boot. During that trip, I was above 7,000 feet for nearly four straight days, and above 9,000 feet for hours at a time.

Power loss was minimal, and fuel economy was not affected tremendously. You can thank real-time ECU engine management for much of it. :)

Here's a link to my post about the trip, which includes proof (i.e., pictures!).
Perhaps my real-time ECU was faulty on July 4, 2008. My power loss was substantial and torque effectively non-existent above 12,000'....while cycling from Idaho Springs (7,526') to the paved road peak of Mt. Evans (14,130'). Regardless, the altitude did not appear to affect any of the mountain goats we weaved through along the way 🐏 🚴‍♂️ 🐑 🚴‍♂️ 🐐
 

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If you study the differences in engine specs between the 2.0 and the 2.5, you'll understand why the 'S' doesn't add much torque.

First, it's worth noting that both engines are basically the same. Each are 2/3 of a 992.1 (read: 911) motor.

Excepting small things such as manifold capacity, the 2.5 S engine really has only two major differences from the 2.0:
  • A larger bore (102mm vs 91mm)
  • The VTG turbo
One of the 'golden rules' of IC engine design is: A larger bore creates horsepower, and a longer stroke creates torque.
This is the biggest reason why the 2.5 doesn't have a large torque advantage. Both engines have the same stroke length.

Turbocharging's basic effect on an engine is largely dependent on the relationship between bore and stroke. That said, it generally creates horsepower more than it creates torque because of the nature of forced induction. (The same rules generally apply for superchargers, too.)
However, note that the VTG turbo's peak pressure is only about 12 psi, while the standard unit in the 2.0s is around 18 psi. Knowing this, the 2.0's turbo tends to kick in later than the 2.5's -- meaning the 2.5's turbo is probably spooling more often, but delivering less PSI when it is spooling. This 'mild' induction greatly favors horsepower creation over torque creation, particularly in relatively low-inertia engines such as ours.

Now you know. :)

Bottom line: In terms of power delivery, the 2.5l 'S' engine has a noticeable advantage over the 2.0 only over 5K RPMs and at speeds beyond 90-95 mph.
I have owned both a '17CS and currently a '18C Base ( both PDK ) and my experience with both cars does not fit your description. The Base relies on boost much more than the S and you can see it on the boost gauge. And the down low torque on the S feels much stronger. When I enter a freeway, I do so in one gear lower in the base. Maybe you can attribute my impression to the VTG turbo. Who knows. But my impression is that the S is faster in all RPMs and significantly. It also drinks more fuel doing so.
 

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But my impression is that the S is faster in all RPMs and significantly
Could that be a "butt dyno" observation versus actual times? Car and Driver's review of the two cars backs up Mike's observations, recording a 4.3 zero to sixty time for the "S" and a 4.4 zero to sixty time for the base. These were 6MT cars. Do the PDK base and "S" cars exhibit different/wider performance stats? C&D also showed the gap widdening from the 1/10th of a second to sixty to half a second in the run to 100, similar to Mike's comments about the "S" exhibiting a noticeable advantage at speeds over 90 mph.
 

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Perhaps my real-time ECU was faulty on July 4, 2008. My power loss was substantial and torque effectively non-existent above 12,000'....while cycling from Idaho Springs (7,526') to the paved road peak of Mt. Evans (14,130'). Regardless, the altitude did not appear to affect any of the mountain goats we weaved through along the way 🐏 🚴‍♂️ 🐑 🚴‍♂️ 🐐
Did you actually ride a bike to the top of Mt. Evans? :eek:
 

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Could that be a "butt dyno" observation versus actual times? Car and Driver's review of the two cars backs up Mike's observations, recording a 4.3 zero to sixty time for the "S" and a 4.4 zero to sixty time for the base. These were 6MT cars. Do the PDK base and "S" cars exhibit different/wider performance stats? C&D also showed the gap widdening from the 1/10th of a second to sixty to half a second in the run to 100, similar to Mike's comments about the "S" exhibiting a noticeable advantage at speeds over 90 mph.
@DPC : Facts, objective measurements, and observations by those here and elsewhere refute most of your post.

How a car 'feels' when going fast and how fast it actually is are two completely different things. It's well documented that the 2.5 'feels' significantly different than the 2.0. That's almost certainly due, in large part, to the VTG turbo, which does have a smoothing effect to power delivery. The 2.5 also has a throatier sound because of the larger bore -- that, however, is placebo because 'throatier' aurally implies bigger, and bigger subconsciously implies faster.

Look: objective testing has confirmed, time and time again, that the 2.5 S has only a .1-to.2-second advantage over the 2.0 base in short timed acceleration tests. IIRC, the 2.0 base actually outperformed the 2.5 S slightly in a couple of non-power-related tests, too -- skidpad and slalom. But the differences are slight. In effect, with the exception of braking (which the S has a notable advantage on, though both cars' brakes are superb), the overall performance difference is essentially a wash between the two models and comes down to the skill of the driver and the nature of the road.
 

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Perhaps my real-time ECU was faulty on July 4, 2008. My power loss was substantial and torque effectively non-existent above 12,000'....while cycling from Idaho Springs (7,526') to the paved road peak of Mt. Evans (14,130'). Regardless, the altitude did not appear to affect any of the mountain goats we weaved through along the way 🐏 🚴‍♂️ 🐑 🚴‍♂️ 🐐
Daaaamn. MAD props! (The mountain goats were out in force when I was there, too. Held up traffic on the road, and one male actually rammed a Toyota front fender ... I feared that more than driving off the road the rest of the way down, LOL!)
 

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@DPC : Look: objective testing has confirmed, time and time again, that the 2.5 S has only a .1-to.2-second advantage over the 2.0 base
Really? Porsche themselves show the gap to be nearer 0.5 and higher again in other measures.

Irrespective of how conservative Porsche’s own figures are, they must surely provide a more measured reflection of the difference between the two engines (unless of course you believe they have reason to reflect one in a better light tab the other).

And, sorry, but I also disagree with your earlier claim that the 2.5 only has an advantage above 5,000 rpm. Looking at both torque and power stats, the larger engine shows a consistent 10% improvement from 1,000 Rpm right through to 5,000. (12% @ 6,000 rpm, and 14% from 6,500 to 7,500)
 

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Really? Porsche themselves show the gap to be nearer 0.5 and higher again in other measures.

Irrespective of how conservative Porsche’s own figures are, they must surely provide a more measured reflection of the difference between the two engines (unless of course you believe they have reason to reflect one in a better light tab the other).

And, sorry, but I also disagree with your earlier claim that the 2.5 only has an advantage above 5,000 rpm. Looking at both torque and power stats, the larger engine shows a consistent 10% improvement from 1,000 Rpm right through to 5,000. (12% @ 6,000 rpm, and 14% from 6,500 to 7,500)
It's known throughout the auto industry that Porsche fudges numbers -- as many manufacturers do -- to preserve make-model hierarchies and market niches. The 718 is no different. In fact, VW AG is one of the worst with this, and has been for decades. Never, never, EVER believe what a manufacturer says about its cars.

That said, independent dynamometer figures clearly indicate that the power gap between the stock 2.0 base and 2.5 S motors is narrower than Porsche states -- especially regarding torque. Also keep in mind that the S model is heavier, particularly in unsprung weight: brakes and wheels. This makes a difference with applied power.

I'm just reflecting what objectively provided numbers tell me.
 

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I suspect for every dyno figure I provide you’ll dig out others showing a different view. The point is no two engines are the same. Hence why I feel Porsche’s own figures are a fairer view of the gap.

Sorry I don’t know the weight difference of the slightly thicker brake disc but I suspect neither of us would notice the difference.
 

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It's known throughout the auto industry that Porsche fudges numbers -- as many manufacturers do -- to preserve make-model hierarchies and market niches. The 718 is no different.
Spot on. "If" Porsche quoted a .1 second difference in zero to sixty times between the base and the "S", just how many less "S" cars would they sell? :unsure:
 

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My recollection from reading car mag reviews is that in the mags' tests the 718 consistently came in a bit quicker than Porsche claimed.
 
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