982 GT4 Spyder?
#931
Rennlist Member
Do I have this right:
The hp is the same (420) whether it's a 3.8 w/X51 or a detuned 4.0, but a detuned 4.0 is preferable (and it's what many were hoping for in the 982 Spyder/GT4) because a 3.8 w/X51 will deliver more power up top at a higher/limited rev range with smaller gains down low and mid-range, whereas a detuned 4.0 would have provided more accessible power across the entire rev range.
Is that a correct statement? If so, can someone explain for those of us who are mechanically challenged why this would be the case. What is it about adding X51 to the 3.8 that results in the power only coming on at the top end rather than across the entire range? Put another way, why can't the accessibility of the 420 hp achieved by adding the X51 to the 3.8 be replicated down low and mid-range like on a detuned 4.0?
Personally, I find the 981 Spyder has more than enough power "as is" so an additional 45 hp on the 982 would be lost on me, even more so if that hp wasn't noticeable down low and mid-range.
The hp is the same (420) whether it's a 3.8 w/X51 or a detuned 4.0, but a detuned 4.0 is preferable (and it's what many were hoping for in the 982 Spyder/GT4) because a 3.8 w/X51 will deliver more power up top at a higher/limited rev range with smaller gains down low and mid-range, whereas a detuned 4.0 would have provided more accessible power across the entire rev range.
Is that a correct statement? If so, can someone explain for those of us who are mechanically challenged why this would be the case. What is it about adding X51 to the 3.8 that results in the power only coming on at the top end rather than across the entire range? Put another way, why can't the accessibility of the 420 hp achieved by adding the X51 to the 3.8 be replicated down low and mid-range like on a detuned 4.0?
Personally, I find the 981 Spyder has more than enough power "as is" so an additional 45 hp on the 982 would be lost on me, even more so if that hp wasn't noticeable down low and mid-range.
Still, we don't really know what Porsche is doing. They could do a 3.8 with a multi-flap intake ala 991.2 GT3 that provides a flatter torque curve down low and up high, who knows. I don't think the 718 GT4/Spyder will get the x51 exactly since even the GT3 didn't get a fancy aluminum intake manifold. I think they'll have a new (plastic) intake manifold specific to the GT4 with a full 911 size tb (finally) and other intake/exhaust revisions to extend and push torque higher in the rev range to get their 420hp w/o actually increasing peak torque much since the 981 is already on the edge of the torque limit of the gearbox which was carried over to the 718. That said, if you already have a 981, might as well call Deman or BGB and go 4L x51 now instead of waiting another year or two. My 4L X51 has been running like a champ since before the 718 Spyder/GT4 speculation threads existed
#932
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^^^^^^ Thanks for your detailed explanation. The issue is clearly more complex than my simplistic understanding, but I have a much better sense of some of the variables at play that Porsche will be working with. Appreciate it.
#933
Good explanation. Unless the 718 Spyder offers a dramatic improvement over my 981 with Dundon race headers, I will pass. The ability to spec one for MSRP might sway me, but that would probably be about it. Otherwise, will hold for a few more years and perhaps go the 4.5L route that Dundon keeps talking about should I desire more power. Seeing as I didn't even bother with the tune, I doubt I will -- but 4.5L so who knows.
#934
Rennlist Member
Good explanation. Unless the 718 Spyder offers a dramatic improvement over my 981 with Dundon race headers, I will pass. The ability to spec one for MSRP might sway me, but that would probably be about it. Otherwise, will hold for a few more years and perhaps go the 4.5L route that Dundon keeps talking about should I desire more power. Seeing as I didn't even bother with the tune, I doubt I will -- but 4.5L so who knows.
agree. Seems like the performance of the 981 w Cobb tune, ipd plenum / gt3 TB, and headers is on par with the new rumored 718 Spyder. 🤔
#936
Rennlist Member
420hp is huge in Porsche land. That's +35hp! 991.2 GT3 got +25hp, GT3rs got +20hp. 991.2 GTS got +20hp, 991.2S got +30hp. I know 420hp seems like nothing burger these days but it's still a solid gain between generations.
#937
Rennlist Member
correct. I was pushing 420+ hp with my modifications. It definitely makes the car come alive and gets rid of all of the flat spots in the rev range. Let’s speculate that the 718 will do the same... still hoping that they surprise us with a 4.0L.
#939
Race Director
same. my spyder was a pleasure to drive after TB, sport headers and Cobb ECU tune. dramatic difference from the stock engine. i can't imagine that this significant difference wouldn't have happened if the engine hadn't been so neutered from stock. i wonder if the new engine will have such responsiveness for tuning.
#940
Three Wheelin'
I never considered a detuned GT3 a viable option. Too expensive. 3.8 + X51 setup has proved to be effective in the past. Budget-friendly to stay within the price curve. All they had to do is to make it compliant to new regs. They may have tested various engine setups, including turbo. But, that could have been for a # of reasons. That's what product development/testing is all about. Those who advocated against it argued that there is no production 3.8. Well, with just-in-time manufacturing and supply chain management, you can pretty much spin up a line in a short period of time. The tooling is already there. The volume is more than enough to make a tidy profit for all the parties involved.
If X51 peaks power near the redline, would be a great news for guys like me. Even among enthusiasts, guys like me are a tiny minority. I don't want low and mid-range torque. Just make it linear and peak near the redline. If I want to pass or enjoy the imminent straight, plan ahead; drop a gear or two and be in the sweet-spot of rev range. And, get ready for the rush and soundtrack! To me, that's an essential aspect of driving! Of course, lower gearing makes all these even more enjoyable. Sadly, Porsche thinks the gearing is fine! So, we got no prayer there.
Those who are expecting a dramatic improvement in performance from 981, are in for a disappointment! That's not how Porsche rolls! Think evolution; not, revolution! Each model cycle sees incremental and evolutionary progress. To me, that's perfectly fine! These days, we may be seeing slightly more than HP jump, if any, between cycles due to HP wars brought on by turbos/hybrids/electrics. Porsche doesn't usually participate in HP wars. They know perfectly well that it's all about the overall package and driving dynamics. For the street, I actually don't want more power than the 981! I value the driving dynamics and styling more than power/torque.
If X51 peaks power near the redline, would be a great news for guys like me. Even among enthusiasts, guys like me are a tiny minority. I don't want low and mid-range torque. Just make it linear and peak near the redline. If I want to pass or enjoy the imminent straight, plan ahead; drop a gear or two and be in the sweet-spot of rev range. And, get ready for the rush and soundtrack! To me, that's an essential aspect of driving! Of course, lower gearing makes all these even more enjoyable. Sadly, Porsche thinks the gearing is fine! So, we got no prayer there.
Those who are expecting a dramatic improvement in performance from 981, are in for a disappointment! That's not how Porsche rolls! Think evolution; not, revolution! Each model cycle sees incremental and evolutionary progress. To me, that's perfectly fine! These days, we may be seeing slightly more than HP jump, if any, between cycles due to HP wars brought on by turbos/hybrids/electrics. Porsche doesn't usually participate in HP wars. They know perfectly well that it's all about the overall package and driving dynamics. For the street, I actually don't want more power than the 981! I value the driving dynamics and styling more than power/torque.
#942
Rennlist Member
Given the current torque and 0 to 60 specs on the 718 Boxster GTS, Porsche won't have difficulty gerrymandering the 0 to 60 time to where they need it to be. First of all, even if they slap in a power kit 9A1 motor and don't mess with it at all, the torque is higher than the current Boxster GTS. Also, plenty of other tricks they could do, with the pdk transmission, with the width and compound of tires, Etc. But they're doing it all for show, really. I don't think they really care about that number too much.
#944
I guess I am in the minority wanting more power. If I get the chance I will definitely upgrade. Especially if I can customize my car to how I want. That opportunity alone is very enticing. Also I like the rear LED lights and the overall silhouette of the car. I don't like the interior vents and the Sport Chrono clock altogether. But I guess it's not enough for me to not want the newer one. And if a car comes from factory without me needing to tweak or feel there was more left on the table - all the better! Another good argument for me to swap is especially if the rumor is true that mechanically both the GT4 and Spyder get the same exact hardware - suspension/wheels/tires. Then it's a no-brainer! But how much of that is true I do not know. Time will tell. Bummed they got rid of the Sapphire Blue color though. That color turned everyone's heads whenever I drive my Spyder!
#945
Rennlist Member
I guess I am in the minority wanting more power. If I get the chance I will definitely upgrade. Especially if I can customize my car to how I want. That opportunity alone is very enticing. Also I like the rear LED lights and the overall silhouette of the car. I don't like the interior vents and the Sport Chrono clock altogether. But I guess it's not enough for me to not want the newer one. And if a car comes from factory without me needing to tweak or feel there was more left on the table - all the better! Another good argument for me to swap is especially if the rumor is true that mechanically both the GT4 and Spyder get the same exact hardware - suspension/wheels/tires. Then it's a no-brainer! But how much of that is true I do not know. Time will tell. Bummed they got rid of the Sapphire Blue color though. That color turned everyone's heads whenever I drive my Spyder!