GVA-SFO

Yes, we can find great plenums (i.e.: IPD)
Yes, we can find high diameters throttle box
Yes, we can find great intake lines with performances air filters
Yes, we can find good performance exhaust lines
Yes, we can find tuners that knows how to get a better "remap" of the ECU of the engine

But...
NO, there are no performance intake manifolds with performance runners available
(The OEM component is one of the weakest part of the M96 for 986.)

Why ??????
Any people would have an idea ?

AnthonyGS

My belief is that it’s too low a volume and there are too many manifold variations to make a big profit. You can get LS manifolds because they are all compatible and there are far more in use. The M96/7 have many variations and they are not even compatible from one installation to the next. The GM LS intake manifolds are compatible with 21 years of production now. A Porsche intake manifold has 2 to 5 years of compatibility and a much lower volume ( # out there).

You want a better intake, custom fabrication is the path.

GVA-SFO

Thanks AnthonyGS, I'm not so surprised with your answer, it makes plenty of sense.

I went already "this way" for the exhaust, as, in my side, I'm not a "noise maker", so my desire was to have the best possible flow, keep the cats, (make it performance using 200 cell cats).
My observations were that in all the 3rd parties, "performance" exhausts are all more oriented to be "more noise", ..than have a better flow !
(I'm all but not like a Ferrari driver with Tubi exhaust, ..that drive it with ear plugs !)
But, I'm still convince that exhaust flow is most probably easier to design, compared to the intake flow that is much less "logical" !

I can report here one thing that I learned "on the field", and that is all but not in the specs. Typically the Porsche way.
When you read the specs of a modern GT3 you see the numbers that we all know.
But, ..a GT3 when it runs at high speed (I'm talking above 150mph), the 2 air scoops that are in the entrance of the intake starts to act as high pressure maker, acting like a turbo. The ECU of the car knows that (speed, pressure, and etc..) and do act accordingly, i.e.: ready to push more gas on the intake, or, one thing that is clear : at high speed, a GT3 has much more HPs, ..than hat is written on the specs.
I discover this being on fast track (i.e.: Paul Ricard, "le Castellet"), when the "Mistral" straight (1.8 km, or 1.2 miles !) is open without any "chicane" on the middle of it (a quite rare condition.)
With no chicane, and when speed over 170mph is possible, ..the modern GT3 becomes "impossible to beat", they just accelerate for ever.
Trying to understand what's up, and talking to high end Porsche engineers, ..you end up catching this very unknown truth !
For sure, you will never find this situation on open roads, ..Nor in any possible measurements on dynos !
But, yes, I'm ready to take any bets that the HP's of GT3 are (much) higher than the spec ones, ..on high speed.

Or : Intake air flow is "close" to real rocket science: all, but not easy !

Btw, it is interesting to see the runners of the M96 X51 option, they looks quite nice. But, I doubt these could be used as a base on the M96 of a 986, the vertical "space" is an expensive real estate !
And thinking about "inverting" these (front to rear). I do not know if Boxster user have been able to integrate this part on 986 ?

It makes me think about the "runner" of a car that I know quite well, (not common, or even more: extremely rare in the USA: the Lotus Exige V6 Cup). In the Komo-Tec kits (the Master tuner of these cars in Europe, who is based just few miles South of the Nürburgring !!), it is equipped with a great fast flow air to water exchanger, ..located inside the "common runner". From here, the water is electrically pumped to the front, to be cooled down by a radiator.
The great thing is the integration of this exchanger, extremely well (hand) build, located in a hand made kind of sub intake box, (acting as "runner") that is located in the center of the V, this to have air in the lowest possible temp going in.
(As you would think, Komo-Tec kits do increase the flow of the compressor !)

Well, at this moment, no action in this direction, ..but thinking and observing !

mikefocke

Perhaps the answer is that, when you think you have a design, you run into the restrictions within the head design used in the early Boxsters. I think Jake has written of this.

Quadcammer

just install a 996 intake.

GVA-SFO

..yes, and possibly a X51 one !

One that looks even better is a 997 X51.

GVA-SFO

Some interesting “data” :


By the way, on the 996 case, from the above, I can read that :
. Modifying the Intake manifold
. Modifying the cylinder heads
. Modifying valves inserts
. Modifying the camshafts
. Modifying the ECU map
..is what was needed to have a gain of 19 hp ! (on the 996/I, in 2000, i.e.: 14kW)


996 with X51 option :




In the aviation business, we often hear “a beautiful plane is a good plane !”
I think, this should be true too on intake manifolds : (997 / X51 intake manifold)




Here ..into a Cayman !




I wonder why not running the shift cables under the top center part of the manifold ?