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I am looking to add some hp to my 2015 BGTS. I was initially thinking of going with a SoftTronic tune but saw an add in the latest Excellence for a plenum upgrade that would give about the same hp for a similar cost. Anyone have any recommendations between the two options? I use the car mostly on street but it is the few track days a year I do that has me wanting the extra hp. Thanks.
Plenums and bigger TB do nothing for the 981 on their own without a tune to go with it, and even then its single digit HP gains all the way up at redline where you will never be on street car. A plenum/TB swap by itself without a tune has shown on real users dynos to actually lose HP/Torque in some cases, or cause cel warnings because the ECU isnt happy with the flow change.
They are snake oil on their own as these cars are not air starved on the intake side, and no one has ever shown a user dyno that shows anywhere close if anything at at all to what the manufacturer claims for the plenum/TB all on its own. The only decent gains on these cars come from long tube headers and a good tune, and even then its a very high Dollar to HP ratio for what you get as you only do so much with a NA motor. Porsche doesn't leave a lot on the table on these engines.
You have the GTS model, so your bump will already be less no matter what you do because your baseline HP is already higher than the S model to begin with. Headers and tune alone can get the 3.4L to 365 HP at the crank, but again you are looking at 5K or more to get there
Plenums and bigger TB do nothing for the 981 on their own without a tune to go with it, and even then its single digit HP gains all the way up at redline where you will never be on street car. A plenum/TB swap by itself without a tune has shown on real users dynos to actually lose HP/Torque in some cases, or cause cel warnings because the ECU isnt happy with the flow change.
They are snake oil on their own as these cars are not air starved on the intake side, and no one has ever shown a user dyno that shows anywhere close if anything at at all to what the manufacturer claims for the plenum/TB all on its own. The only decent gains on these cars come from long tube headers and a good tune, and even then its a very high Dollar to HP ratio for what you get as you only do so much with a NA motor. Porsche doesn't leave a lot on the table on these engines.
You have the GTS model, so your bump will already be less no matter what you do because your baseline HP is already higher than the S model to begin with. Headers and tune alone can get the 3.4L to 365 HP at the crank, but again you are looking at 5K or more to get there
For what it's worth I have the plenum, tb and headers with an ots Cobb tune and in mid summer heat the car put down 329 at the tire. The notes from my tuner were it's running fat (Cobb is known for this) so there might be some on the table but not much. We did all the performance mods at once so I don't have much in terms of how they compare. Coming from the world of turbos it's hard to look at those gains. If I were going to do it all over again I probably would have stuck with the exhaust mods.
If your car isnt a DD the headers would be my favorite mod. If you like to fly more under the radar the intake route might be better option for you. People can say what they want but sounding fast definitely adds to the fiz and the experience... Even if you aren't going any faster.
Having said all that...
I think there are some other mods that might have bigger pay offs on track than power adders. A proper track alignment and if you can add some negative camber and proper rubber that will be the biggest bump and confidence and lap times. After that I'd maybe start looking at the exhaust/engine...
FWIW I'm running the Softronic tune and BMC Filters on my 981 CS and it has made a very noticeable difference in how the car performs, it feels a fair bit stronger in the mid range than stock. I'd go that route again without hesitation.
The sport headers (with 200-cel cats) or the race headers (catless, if your local laws allow them to be streetable) with a good ECU tune is the way to go for the Boxster/Cayman. Their intake system design is already so direct and efficient that there is not much room for improvement there. On the other hand, since their exhaust system is not as direct as that of the 911's, the Boxster/Cayman will benefit from high-flow headers and a tune to maximize their effects. Meanwhile, the 911's will benefit from the IPD plenum and the GT3 TB because their intake system is not as efficient due to the engine placement.
Since the OP has the GTS, tune alone will not make much of a difference. He needs headers to realize a substantial power gain.
I went with the FVD Sport Headers (designed and made by M&M Exhaust of Germany who designs and supplies exhaust systems to Porsche Motor Sports) along with the FVD tune and can't be happier.
As others have said. I come from first hand experience with the plenum/TB upgrade without tune at first. I noticed a huge drop in low end and mid range power. I did feel faster revs once it got above 6K rpms. That was without the tune. I didn't get the power back until I tuned it.
I would do headers and drop in filters first. Then if you really want the Plenum and a tune. You will gain more with the tune, the plenum just locks the last potential bit.
This is an old thread so I hope someone jumps in with a response. I have a 981 Base that I added the IPD Plenum and 82mm throttle body mainly because I found them on ebay for $500. Fortunately they were in pristine condition. I go the CEL after installation so I added the FVD tune which eliminated the light and definitely added some power(no dyno) but it still seems weak between 3500-5000 rpm. My next addition will be Topgear street headers which are the identical design to FVD's and go for $1700. They have a 200cell cat but not the HJS cat and they are 304 stainless unlike FVDs T316 Lightweight Stainless which are up to $5393. I've read numerous reviews on Topgear headers and they are nothing but excellent.
My question is: aren't all the off the shelf tunes going to be about the same? There's got to be only so much you can do without having the car in the tuners hands and on a dyno.
I hope someone responds because I read multiple threads and this question has not been addressed. TIA dlbehrns
Some shops may offer an off-the-shelf tune for the hardware you intend to install but for the best results you need live mapping (specific to your car) AFTER you’ve added all the hardware. This will reduce the flat spots/drop in torque you may otherwise experience. This applies to all tunes regardless of vehicle manufacturer. It’s a pain but no way round it IMO
You would need an updated tune after installing the headers to get all the power the headers can provide. When you purchase an FVD tune, and later purchase their headers, they upgrade the tune for free.
You would need an updated tune after installing the headers to get all the power the headers can provide. When you purchase an FVD tune, and later purchase their headers, they upgrade the tune for free.
What gedwin said. Even if you don't buy headers from FVD, they will update the tune for a fee. Having the tune updated to accommodate the headers is very important to take full advantage of the upgrade. This is where FVD is different (and better IMO) from OTS tuners.
I had first bought the FVD tune and later added their Sport Headers and they updated the tune for free. They gave me a nice discount on the headers because I had become their "premium" customer by purchasing their tune. You may want to find out what kind of discount FVD is willing to give now. I know nothing about Topgear products and the FVD headers will never be $1,700. However, when you buy the FVD headers (designed and manufactured by M&M Exhaust, one of the top exhaust system producers in Germany), you know you are getting one of the bests that money can buy.
I just got the Fvd tune for my soul long tube headers. It’s better than just the stage 1 Fvd tune. Not earth shattering on my base 981 cayman but it’s quicker. The sound alone makes car so much fun. Right now the headers tune, PSE and x73 make this car perfect for the street. The mods are done, only maintenance for me for now. Would love to try the soul exhaust and compare to my PSE, but I spent enough this year and the car is great.
11-12-2022, 02:01 PM
Tune or plenum?
