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Installed IPD Intake Plenum on 986 Boxster...Pics & Review

21K views 14 replies 9 participants last post by  Acosta3211  
#1 ·
So, I recently installed the IPD intake plenum on my 986 Boxster ('02 2.7L). While the 986 has seemingly always lacked much availability for aftermarket parts compared to what's available for the other models & generations for the other Porsche siblings, this was a mod that I've always wanted to try out.

PART1: Here we go:


Here is the OEM throttle body and plastic T style plenum next to the upgraded larger throttle body and IPD Y style plenum, along with the clamps and silicone reducers.


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Smooth Y design of the plenum, rubber sealing O-ring to mate to the larger throttle body.


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The Cayman 3.4L IPD plenum is modified for the 986 eGas boxster models.


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I believe the modifications for the 986 fitment (compared to stock for the Cayman application) is this larger nipple, and machined back piece.


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Here is a comparison of the stock boxster 69mm throttle body next to the upgraded 75mm throttle body. (For simplicity sake, I'll refer to these as 69mm and 75mm, although the actual dimensions measured accurately are more along the lines of 68.xx mm and 74.xx mm). The larger "75mm" throttle body comes on the NA 996 Carreras, 987 Boxster & Cayman, 997TT, 997 NA, etc.


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OEM T-pipe removed and new IPD silicone reducers set on the oem intake manifolds.


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"Modified" Cayman S IPD silicone hose (cayman hose coupled to another hose via tube for temporary setup)


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More to come...
 
#2 ·
Part 2:

To replace the temporary silicone intake hose setup that used the Cayman hoses mated by an adjoining pipe is the new one piece IPD silicone hose made specifically for the 986 Boxster fitment.

Very nice piece with multi-ply layer silicone... Also decided to change my upgraded larger 996NA throttle body for the same size 997 Variant. Same 75mm throttle body size (74.xx mm), but I liked the color/finish on the later 997 models better. (Yes, OCD pickyness, I Know)


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OEM throttle body next to the new larger throttle body. ~6mm Larger inner diameter.


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Stock OEM plastic intake piping (from throttle body to MAF tubing & filter box).


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Temporary Intake setup with Cayman piping, and misc. couplers/pipes.


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New IPD multi-ply layer silicone formed 986 Boxster one piece intake hose pipe with smoother finish, and full ~3" inner diameter all the way through from throttle body to MAF pipe housing, pre-air filter box housing.


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As you can see, the new one piece silicone intake hose pipe is pretty nice compared to the other previous setups.


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IPD Plenum in place, ready for new throttle body to be bolted back in..


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New throttle body in place...


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Plenum, throttle body, and intake hose in place. Removed unnecessary bracket below.


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Driving impressions to come in part 3...
 
#3 ·
Part 3: Driving Impressions & Review...

Parts Added:

IPD Plenum setup for 986 Boxster (modified version of Cayman plenum, see pictures above for explanation), 75mm Porsche throttle body (74.xx mm 996NA/987/997), and new IPD 986 boxster silicone intake hose.

Fit & Finish:

The IPD intake plenum is a very solid and well build piece. It is a cast aluminum plenum, feels lightweight, and has an orange colored smooth inner tract lining. The inner diameters of the 3 openings for the plenum are larger than stock, and the Y design seems incorporated with a well thought out design that doesn't sacrifice overall air volume, as the overall plenum is larger than stock.

The 75mm porsche throttle body bolts straight onto the IPD plenum and is perfect fit. Like stated in my earlier posts, you could use the 996NA throttle body, the 987 Boxster/Cayman TB, and the 997 NA & TT throttle bodies, etc..

The new IPD intake piping silicone hose is a one piece fitment from the throttle body to the oem airbox's MAF tube connection, or in my case, to an aftermarket MAF tubing to a "cold" air intake, or cone filter. This new larger hose replaces the stock intake piping. The fitment of the hose is great, and didn't require any modification for fitment. The hose is a multi-ply silicone hose and feels very solid and sturdy. It is currently attached to the TB and MAF pipe with worm-clamp connectors, but I'll be changing these out for T-Bolt clamps and dual beaded T-bolt clamps (although this is overkill and unnecessary).

Installation:

Just a generalized installation summary, although if anyone would like a full DIY, let me know. Removal & installation is very straightforward and can be done under an hour overall. If you're handy, of course you could get it done in 15-20 minutes for the installation.

1. Put the 986 Boxster top in "service mode" & remove the engine cover
2. Remove the OEM plastic intake piping
3. Remove the OEM throttle body and T-pipe as a single unit
4. Fit the IPD silicone coupler/reducers to the OEM intake manifolds
5. Center the IPD plenum in place between the intake manifolds
6. Install new 75mm throttle body to the plenum.
7. Install the IPD silicone intake hose piping
8. Secure/Tighten all clamps and connectors after adjusting proper fitment.
9. Reset ECU & calibrate throttle body
10. Drive aggressively while the ECU readjusts

* Key Note: Make sure you have a healthy MAF sensor! This is very important either way, whether you are stock or modded.

Driving Impressions & Feel:

While a bit of a skeptic, I always do my homework and research on any mods prior to getting into it. I've read plenty of reviews and talked to many people who already have the IPD plenum who have felt great gains, whether it be via the "butt-dyno" or measured by actual dyno before/after runs. As great as that always sounds, I would never actually know how it would be for my personal car and setup until I tried it myself.

My impressions of the new IPD intake setup: Just getting on the gas at low speeds out of the parking lot or onto the street, I could feel the car just rev up faster and just want to go. That immediately suppressed my fears of the potential to lose some low end torque grunt. Fortunately, it felt more powerful on the low end, revved up faster, and did it all much more smoothly and felt much less restricted in doing so.

Midrange and high end feel great. The car simply pulls harder throughout the entire powerband. The throttle response is quicker, and there is less hesitation to accelerate. The sound is also more aggressive, and overall power delivery is very smooth and linear.

Getting on the freeway onramps and overtaking on the freeway no longer feel like a chore, as the car pulls much stronger than before.

This has been a great mod. In fact, it is probably the most rewarding out of all of my peformance mods thus far.

While I don't have any dyno charts to post (and I sure wish that I had done a before and after dyno run), I can definitely say that I'm very happy with the mod, and that I definitely feel that the car pulls much harder and feels faster.

If I had a choice to do it all over again, I definitely would without any reservation.
 
#12 ·
Hey don't go giving me props....I don't write the article. lol. :taunt:

Drop in gas mileage...umm tricky. I drive my car hard so then with more power I must be using more fuel, but I've not paid attention...a luxury of living in the Middle East I guess. Now if I was back home in Europe then I would probably pay a bit more attention! In the US I probably wouldn't caress fuel is still very cheap in comparison ;)
 
#13 ·
The 3.2 is a particularly difficult engine to tune as the valve sizes and cam timing offer a more significant restriction than on the later 3.4. Unlike other mods this does give a power increase throughout the rev range , so the gain on paper is only part of the story. The engine also has a deeper induction note after install. If you are looking to achieve this result at less cost , one option is to fit a 996 plenum tee and make up a custom intake tube to fit onto the airbox. The throttle body is a common part used on the 3.4 boxster/ cayman and the 996 3.4/ 3.6 engine as well as cayenne V6. The IPD only gives marginal gains on this engine , in fact its not listed as having any gain with the standard throttle body on the IPD site for the 3.2 engine other than throttle response.