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Yep, one of most famous Porsche engine builders with a 2 year waiting list will tell you they are useless unless you go bigger than 3.6. The exact same question came up to Dundon Motorsports, and the guys there said they dont bother on the 3.4 because the dyno shows little if any gains. They actually made their own custom intake runners to make it work better on the 3.8 GT4 and they got very good results, but only in conjunction with the different intake.

I really want this to be a thing and have since I bought my car 7 years ago. I have been looking for any real dyno proof other than from IPD themselves for 7 years now, and not a single dyno from any actual customer out there shows anything other than a couple HP at 7100 RPM where no one drives, and it lost torque under the curve where we do drive.

The most conclusive test was a member who did a bone stock 3.4S run, then added the Plenum and 82TB and his car lost 10HP and 10lbs of torque over the stock run. He then had a custom dyno tune done to try and get the performance back and they eventually regained 17HP and got the torque back for a total of 7 peak HP but only near redline and about 2-3HP down in the driveable range. Not worth it for the cost and trouble IMO

It was at this point I just gave up considering it as there just isnt any real word factual data that supports their claims. Anyone can make a dyno run look great for marketing purposes, and people that tune these engine for a living seem to agree with those minimal results as well.

One of the guys who started with a 981 GTS did headers and pro tune like I did and has extensive before and after track data and dyno runs which show his motor hitting 365-370 crank HP which is known to be the limits of these cars, and he isnt running any plenum or TB to get those exact same results that others who are are also getting, so I am comfortable that my car is making the same power as everyone else with or without any bigger TB. That is 15-20HP more than the base Carrera using the same motor which was rated for 350. Porsche limited the power on the 981 variant by not allowing the throttle to fully open to 100% but a tune removes this restriction

There was also a member here who had the full package of headers, pro tune and plenum setup who removed the plenum and TB to sell before trading his car in and admitted he detected zero difference in the cars performance after removing it, so again there is just way more evidence against this mod having any sufficient value other than from the company who makes it and sells it.

I would reconsider if anyone could produce ONE real customer dyno from stock to upgrade, and even half of these claimed manufacturer values being produced and remember they are making these claims with no tune and nothing but a hardware change. The problem is people make 2-3 changes at a time and then throw a tune on top of it and claim its so awesome. It doesnt work that way and you have no idea if you would have made the exact results or possibly even better with only 1-2 of those changes
 

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The plenum mod has to be the most controversial upgrade on the market. There's a lot of conflicting information from reputable sources which makes it frustrating.

IPD told me the same thing. "Given your full exhaust and flash tune, go for the competition setup". My engine builder says the competition is not beneficial on a smaller 3.4L. A specialist at SOUL Performance, who actually sells the plenum/TB on their website, told me to forego the plenum altogether months back. If I were in your shoes, I would get the competition and 82 mm TB. I tend to be a risk taker and would have buyers remorse if I bought the standard setup. No harm can come with more airflow. Worst case scenario, you don't gain any power but do have more intake noise. I'll reiterate though. Definitely get a tune afterwards and if it's in your budget, a set of headers. Headers make substantial power on our platform.
Yeah! This is perhaps the most controversial mod. Noted on the headers. Just can't get myself to pull the trigger due to MOT concerns.
 

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Yep, Jake Raby, one of most famous Porsche engine builders with a 2 year waiting list will tell you they are useless unless you go bigger than 3.6. The exact same question came up to Dundon Motorsports, and the guys there said they dont bother on the 3.4 because the dyno shows little if any gains. They actually made their own custom intake runners to make it work better on the 3.8 GT4 and they got very good results, but only in conjunction with the different intake.

I really want this to be a thing and have since I bought my car 7 years ago. I have been looking for any real dyno proof other than from IPD themselves for 7 years now, and not a single dyno from any actual customer out there shows anything other than a couple HP at 7100 RPM where no one drives, and it lost torque under the curve where we do drive.

The most conclusive test was a member who did a bone stock 3.4S run, then added the Plenum and 82TB and his car lost 10HP and 10lbs of torque over the stock run. He then had a custom dyno tune done to try and get the performance back and they eventually regained 17HP and got the torque back for a total of 7 peak HP but only near redline. Not worth it for the cost and trouble IMO

It was at this point I just gave up considering it as there just isnt any real word factual data that supports their claims. Anyone can massage a dyno run to make it look great for marketing purposes, and people that tune these engine for a living seem to agree with those minimal results as well.

One of the guys who started with a 981 GTS did headers and pro tune like I did and has extensive before and after track data and dyno runs which show his motor hitting 365-370 crank HP which is known to be the limits of these cars, and he isnt running any plenum or TB to get those same values that others who are are also getting, so I am comfortable that my car is making the same power as everyone else with or without any bigger TB. There was also a member here who had the full package of headers, pro tune and plenum setup who removed the plenum and TB to sell before trading his car in and admitted he detected zero difference in the cars performance after removing it, so again there is just way more evidence against this mod having any sufficient value other than from the company who makes it and sells it.

I would reconsider if anyone could produce ONE real customer dyno from stock to upgrade, and even half of these claimed manufacturer values being produced. The problem is people make 2-3 changes at a time and then claim its so awesome. It doesnt work that way and you have no idea if you would have made the exact results or possibly even better with only 1-2 of those changes
that was good explain
 

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Here is a recent dyno run I borrowed from one of the members here that tells the story perfectly and validates what most know, and that is the best bang for your buck on these cars is headers and a pro tune. You can see his stock baseline and then how the headers alone give a nice bump of power down in the RPM range where we drive, but then peters out to stock above 5K so the peak HP didn't change much at all.

Then they added the pro tune to remove the throttle opening restriction along with some other tweaks and the difference was huge all the way to redline. They calculated this run to 367 crank HP when the drivetrain losses were factored in, so 17HP more than the 911 engine variant in stock form.

These engines have been in tuners hands for years now and its well established that 365-370HP is all you can get out of them naturally aspirated no matter how many mods you do, and he managed to do it with only two mods. No aftermarket air filters or plenum and TB change required.

There are dyno graphs like this out there from the guys that have all mods done including aftermarket exhaust and they make no more power than this, so I suggest people do a little digging for themselves when they are deciding what mods to spend their money on as the Dollar per HP ratio on these cars isnt cheap as we all know, and to me actual data means more than anecdotal stories, confirmation bias and marketing claims from those trying to sell you something
 

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So what headers you try it, you recommend of who you think it's good in pro tune..
I made this graph with my sport catback "fvd" bmc filter "stage 2" from fvd.. But got big touq on the start loose it in the high rpm

Best regards
 

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All of the major and well known brands of headers, Fabspeed, FVD which are actually made by M&M out of Germany, Dundon, Soul etc are all good choices. I cant speak about the off the shelf FVD tunes as I have never used one, but I can tell you the stage 2 off the shelf Cobb tune is very conservative and a remote pro tune from Fabspeed or a dyno pro tune can unlock a lot more on the Cobb device. Softronic seems to be loved by many as well and show similar pro tune gains on the dyno from those that have them

Unfortunately your graph doesnt tell us much unless you did a stock run first. The actual numbers themselves dont even mean much as they vary wildly from one dyno to the next, so what you need to see is the delta between those numbers. The only way to do that is to have the stock baseline value on the same dyno first and obtain the percentage of change between the two after the mods rather than comparing the actual HP numbers to someone else. Don't expect much gains from just swapping out the exhaust and filters do little to nothing. Its the headers that make the real difference
 

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Here is a recent dyno run I borrowed from one of the members here that tells the story perfectly and validates what most know, and that is the bast bang for your buck on these cars is headers and a pro tune. You can see his stock baseline and then how the headers alone give a nice bump of power down in the drivable RPM range, but then peter out to stock above 5K so the peak HP didn't change much at all.

Then they added the pro tune to remove the throttle opening restriction along with some other tweaks and the difference was huge all the way to redline. They calculated this run to 367 crank HP when the drivetrain losses were factored in, so 17HP more than the 911 engine variant in stock form.

These engines have been in tuners hands for years now and its well established that 365-370HP is all you can get out of them naturally aspirated no matter how many mods you do, and he managed to do it with only two mods. No aftermarket air filters or plenum and TB change required.

There are dyno graphs like this out there from the guys that have all mods done including aftermarket exhaust and they make no more power than this, so I suggest people do a little digging for themselves when they are deciding what mods to spend their money on as the Dollar per HP ratio on these cars isnt cheap as we all know and to me actual data means more than anecdotal stories, confirmation bias and marketing claims from those trying to sell you something
Excellent info and verification...A quality set of headers and tune on the 987/981 will yield a power to weight ratio even greater than a stock 997.1 S. With so much focus on HP, folks overlook the weight of the Cayman. It's ~200 lbs less (curb weight) than a Carrera S. Just as a note, the 987.1 has secondary cats in the exhaust so upgrading to a high flow exhaust will yield some more power so it's certainly a mod to consider.
 
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Ah, yes thanks for the clarification on the 987.1! I had a 1 then 2 and now the 981, so I guess the 987.1 is now ancient history in my mind. Yes, there are those pesky extra cats inside the factory 987.1 exhaust that would be eliminated with an aftermarket exhaust so maybe a better bump with exhaust alone for those driving that model vs the others
 

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Was trying to clean everything but the pipes or hose all broken.. Then I go to the dealer he do not have them. Then I bought a new (not sure if they same quality and heat temperature)
And when I start to fix them I forget the way 🤦🏻‍♂️
 

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Let this be a lesson to everyone.... always take pics along the way

Its an awful lesson to learn

Sent from my SM-G960W using Tapatalk
 

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Let this be a lesson to everyone.... always take pics along the way

Its an awful lesson to learn

Sent from my SM-G960W using Tapatalk
Or if you're a complete incompetent like myself, take it to a professional.
 
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