dsddcd

I wanted to share another 981 Power Kit dyno and results.

Details:
2016 Boxster GTS - 10K Miles
IPD Plenum - (Soul Performance)
OEM Headers w/o Cats
Cobb & TPC Tunes - (Soul Performance)
91 OCT (R+M)/2


Dyno Graph Key
Red is all Stock
Blue is Headers, IPD & Cobb STG II 91 OCT
Green is Headers, IPD & TPC STG I


I can't tell the power difference but the sound is great.

4PTZERO

Interesting findings, kind of toying with this myself. Looks like 20whp ish results, and you're saying you can't feel it but only hear it?

JCtx

Related question: Why that big dip before redline, even with tunes? Never seen that before on a NA engine. Dips, yes, like the 6K+ rpm one. But that huge one rear redline? Never. I'll never tune my cars, but thought one of the benefits was to remove those dips. Maybe not. Thx.

dsddcd

Nope it pulls the same to me but with the "Race" headers the exhaust is much more aggressive.






The graph in general is not very smooth to say the least. Unfortunately I don't know any of the specifics as to why these dips exist but I am sure there are others that do and have tried to work them out.

Unconscionable

Not bad gains, but might need a better tuner... The gains on my 981 Spyder with these exact mods was pretty noticeable.


also, the power band follows the same curve as stock, with the same dips, so it's not like something terrible changed. Looks the same.

guab

Keep in mind the 981 Spyder is a very significantly de-tuned 911 motor and Porsche intentionally left a lot on the table -- opposite of the GTS.

gearFX

Thanks for sharing. So are you alternating between tunes or sticking with one over the other? Looks like TPC Stage 1 tune makes more power than Cobb Stage 2 tune, but the party lasts longer (RPM) with Cobb.

Archimedes

8 percent max HP increase is not going to be noticeable at the seat of the pants.

Archimedes

Yup. Totally different animals.

dsddcd

I have the TPC boxed tune on, I only did the Cobb STG II for reference purposes.

cobalt

I watched a 981 Cayman S have a tune done today. I don't recall the headers it was a custom tune but the power increase was better across the board than what you are showing. They also tried the IPD plenum and got 0 HP gain by using it. They were using a Mustang dyno.

MagicRat

Was the car retuned after the IPD was put in?

cobalt

??

Hoosier_Daddy

This is not the first time I have heard the plenum adds nothing to the equation... not surprised. Even a gain of a few HP here and there makes it a poor way to spend $1000 IMHO. But hey -- gives you something to talk about at the next C&C...

dsddcd

I don't think I would do the plenum again, it looks nice but it is my belief is that the only real gains are from the larger throttle body and that is splitting hairs. The only real value for me is in the tune and headers for sound.