CAlexio

Simple and honest answer... one will drive the ***** off it all over any curvy road we can find, just we drove slightly lower powered versions.

I’m not sure I get the question?

storii

Well, to do just that, I feel the 315hp 981 BS of mine is just enough for me. Maybe it's just me....

rloggie

Simple honest answer. Just fun and exilerating to drive on the street. Take on short trips and blast through the countryside. As much as I love the 981 I miss the power of a 911 Turbo cab and would like the Spyder to come close for a more ideal, to me, car.

Petevb

Higher torque won’t close an 18% power gap with decent gearing. Not the way torque works...

That’s exactly the point. If the GTS is a 15k+ more expensive car Porsche likely can’t let the GT4 out-accelerate it. The old GTS didn’t and even the old PDK equipped Carrera was faster to 60. If the relative price point moves up performance can move up in concert, but they only allow even the GT group so much leeway.

If numbers are that important to you, however, I’d look elsewhere. What you’d get for your money would be a close ratio gearbox (no need to hobble it like last time), a tack sharp, responsive engine, a screaming normally aspirated soundtrack and a track ready dry-sump. That should make the decision pretty easy for the type of driver the car’s aimed at.

FlamsteadHill

While I agree in general principle, there is not enough data in your argument to be validated.

As you've implied, where is it making how much torque and how does that line up with final drive ratios? IOW, an 18% power gap could be over only 100 RPM, and it's horrible on either side.

And of course all this talk about power doesn't address the other bellwethers of Porsche - feel and handling. If all you want is power, buy a Demon. Or at least a ZR1.

Petevb

In theory you’re of course correct- if you choose ratios by throwing darts and draw a power curve like you’ve got cerebral palsy you can make up anything you’d like. In practice, on the the other hand, 18% more power means you’re pulling harder for over 1/4 of the rev range, and for a lot of that you’re pulling much harder.

Overlay any two Porsche dynos you want trying get more area under the curve in even the lower gears with that type of disadvantage- it’s not going to happen. The 991.1 to 991.2 switch to turbos was worth around the eqivilant of 20-25 hp in area under the used power curve (more in low gears, less in higher ones). That’s pretty good, but far less than we’re talking about here.

ajw45

As much as I would LOVE a 9k rpm screaming short stroke engine and close ratio gearbox, I'm skeptical. Even the .2 GT3 gearing is long and they didn't shorten it for the .1 RS either so doing it for the GT4 would be a stretch. Some thoughts I posted a while back on the GT4 board on why I think we'll see a 410-420hp 4L NA engine:

1. 718 Product Range
The recent 718 GTS release with a 15hp bump matches the 981 GTS bump. No surprises so far in the 718 line. A similar bump from 981 GTS to GT4 would put a 718 GT4 at ~410hp.

2. 718 vs 991.2
The 981 GTS was 10hp down from the base 991.1 and the GT4 was 15hp down from the 991.1S. The 718 GTS was released a perfect 5hp down from the 991.2 base. If we close the gap a little between the 718 GT4 and the 991.2S (420hp) we're somewhere around 410hp.

3. GT4 vs GT3 Positioning
The 991.2 GT3 received a 25hp bump with the move to the 4L. A similar bump would maintain the hp gap between the GT3 and GT4 put the GT4 at 410hp.

5. Cost
The GT4 is still the entry level GT car so it needs to come in significantly less expensive than the GT3. Revs cost money. 9k rpm is going mean dry sump, titanium engine components, magic no adjustment adamantium solid valve lifters, dlc coated cams, etc. Oh, and 9k rpm means a whole new gear set too. I'm guessing no change to the redline and no fancy GT3 heads/intake, something more like the current engine. Changing the crank spec to stroke the engine to 4L costs Porsche almost nothing.....

5. Torque
The GT4 Clubsport is pretty down on power where everything else is blown and/or a v8. Plus, with the 718 and 991 lines gone turbo, there's a huge mid-range torque gap to keep up with. Even though Porsche would have no problem getting 410hp out of the 3.8, I bet they'll go 4.0 for the extra torque partly for racing, partly to keep up in a torquey turbo world, and hey, it'll be great for marketing.

Conclusion - I think we'll see an ~410hp NA 4L that's more similar to the current 3.8 than the new GT3's 4.0. Whichever is easier to certify but whether its on the new GT3 engine architecture or not, they won't let it breath and run a lot of revs to compete with the GT3. The old 3.8 made 400hp in the 991.1S so really all Porsche needs to do is stroke it and put in the proper 911 airbox and tb to get the power they want. No fancy materials, no dry sump, easy, reliable, and gtg.

Spyder Man

1. Depending on at what speed...unless a super low gearing drivetrain is used on the GT4 which they won't, in the first 2 gears the GTS with higher torque will be faster and will definitely be faster in the in gear acceleration...from 3rd gear onwards the low torque higher power car will slowly creep up and it will take until fourth gear to actually catches up and then overtakes. We are talking about a 430ps GT4 and if power is only at 400-410ps then slim chance to turn the tide until top speed. Therefore I think there is a very good chance they still drop in a 4L detuned GT3 engine this time round

2. Yeah at this age I rather prefer Porsche GT to do it for me...not a sucker for modding cars anymore... ha ha

Petevb

By that logic the new 991.2 base Carrera (370 hp) should be quicker to 60 and through the 1/4 than the outgoing 991.1 GTS (435 hp), yes? Same 65 hp gap, torque advantage, etc. But the GTS is significantly faster to both figures...?

Again: right concept with torque, wrong conclusion. The Carrera GTS isn’t quicker than the GT3, etc, and more importantly Porsche insures the pecking order is maintained, so if it was in danger of being slower than the Cayman GTS they’d simply turn one of a dozen ***** to make it quicker.

It goes back to “value based pricing”. I’ve been asked to update this old thread, but it will give you an idea:
https://rennlist.com/forums/991-gt3-...tatistics.html

And of course this is exactly what makes the Spyder such a deal as a drivers car. On the performance scale it’s not hugely impressive vs it’s peers, but on an experience scale it’s way up there. A 4.0 liter torque monster of an engine that doesn’t need to pull to redline every gear to make speed would largely ruin that imho, one reason I’m quite sure they won’t do it.

Mark Dreyer

I hope are right. I’ve owned a bunch of Porsche sports cars over the past 30 years. I really feel like this 981 Spyder is the pinnacle in terms of driving enjoyment. No plans to ever sell it. A Spyder with a 9k 4.0 might tempt me though.

NelsonF

I agree fully and have had similar experience. Wouldn't be upsetting to me in the least to keep my existing 981 Spyder. The next will need to have similar special sauce for me to make a change.

ajw45

I know everyone gets all hot and bothered about the mythical 4l flat 6 but an extra .2l doesn't suddenly change this into a big lazy torquey 6.2l ls engine. All things being equal, we're only taking a 5% bump in displacement, call it +10-20 ft/lbs across the powerband. If the shape of the torque curve doesn't change, it just gets bumped, you still need to rev it out and drive just it like the 3.8. Now, with a different intake, cams, etc, Porsche could make a low end torque monster if they choose to but it that isn't necessary just because the engine displacement has increased.

Petevb

Not quite. Stroking the 3.8 is Porsche’s only practical option, and stroking results in a disproportionate increase in torque if you do nothing else. Top end flow hasn’t increased due to restriction through the valves, manifold, etc, so the higher rpms get throttled by trying to suck air through the same diameter straw, while the mid-range has no flow restriction and actually energizes resonant intake runners sooner and better. On a 997.2 GT3 to 4.0 this results in something around a 40 lbs ft bump in the mid-range if you don’t do something about it. Porsche’s own 997 RS 4.0 used not only a different cam but a different intake (with massive diameter runners) to counteract that bump in torque. If you don’t the result is a falling torque curve as you approach redline rather than a rising one, very different sensations. The GT group specifically tries to avoid this with their normally aspirated engines, and I’ll contend that they focus as much on the shape of the power curve as much as the absolute power itself.

More to the point the existing 3.8 is easily capable of hitting the likely power targets, so the only reason to increase displacement is to bump torque. Doing so (with a power band they’d like) would require resurrecting the no longer in production 9A1 and crafting a new crank, rods, cam, intake and pistons. All for an engine that Motorsports has no experience with (it was developed at Weissach, not Flacht). The alternative is sharing the already in-production parts and testing data from the 991 GT3, and using wholesale all the hard won learning and tweaks needed to make the Cup cars reliable- keep in mind the GT4 will go racing. That shared development and production tooling alone more than offsets the additional cost of finger-follower cams, etc in my estimation. More important it would result in a far better final product. The fear is that it might be too good, even at only 430 hp.

Noah Fect

People keep saying that. What are they using in the capital-T 991.2 Turbos, a flux capacitor?

Petevb

9A2. Related, obviously, but enough differences that cross-generation compatibility is tricky- they would need to make many new parts with the associated testing and software to re-create the normally aspirated 3.8. All doable and it would make for a better, lighter engine in the end, but it would cost. With the 9A1 it would have been plug and play from the in-production parts kit...