987 v 986 Air box

[Brad Roberts]

Command decision made:

If we are going to install a 987 air box.. why not switch it over to the larger CaymanS 3.4 throttle body



B

[Marchie]

Yeah, I"m interested keep us updated. It's all interesting JAAY & Brad

[Brad Roberts]

Now.. think about ALL those guy's who have bought the IPD plenum setup. They ALL have these parts sitting around (the TB and TB center section)

FYI: This is not new by any means. Porsche did this EXACT same setup in the 986 50Th anniversary car. Granted it was a Variocam Plus engine, but it was still a 3.2.

Something else.. scared of the larger throttle body? The rubber bellows from the MAF housing to the throttle body? They sell two versions. One for this 3.4 throttle body and one for the 2.7 cars (same one they used in the 50th anniversary 3.2 car)


B

[Brad Roberts]

I think it's a good idea to "help" this area (with a hammer) I didn't, but it would have made it easier to the install the bellows from thew MAF housing to the throttle body. Just a little nudge!! This is were the 86 and 87 chassis differs. They have more room right here.

B

[Kroggers]

Originally Posted by Brad Roberts

Now.. think about ALL those guy's who have bought the IPD plenum setup. They ALL have these parts sitting around (the TB and TB center section)

FYI: This is not new by any means. Porsche did this EXACT same setup in the 986 50Th anniversary car. Granted it was a Variocam Plus engine, but it was still a 3.2.

Something else.. scared of the larger throttle body? The rubber bellows from the MAF housing to the throttle body? They sell two versions. One for this 3.4 throttle body and one for the 2.7 cars (same one they used in the 50th anniversary 3.2 car)


B

As one of the people who has bought the IPD plenum - could you please elaborate on your point. Are you saying I made a bad selection or a good selection?

[Brad Roberts]

I'm referencing the IPD purely from a used parts standpoint

987s owner who bought the IPD will have the throttle body T section (and throttle body) available for sale (since they removed it and installed an IPD)

The 987 3.4 T section allows for the 3.4 throttle body to be installed in this situation for a lot less money!!

Want to go bigger later? Buy the 3.6 T section and install it into the 3.2 plenum, its the same diameter as the 3.4, but allows for the 3.6 throttle body.

Just giving people alternatives



B

[jaykay]

Nice how are you properly running the diverter flap in that Cayman diverter tee? Looks like you have a line going to the AOS for it as well. Which MAF housing did you end with? Perhaps you've loaded a 3.4 flash to have the DME run the extra flap and accommodate the larger MAF housing??

Just curious....I only see one Boxster engine and have to guess at things!

Originally Posted by Brad Roberts

Now.. think about ALL those guy's who have bought the IPD plenum setup. They ALL have these parts sitting around (the TB and TB center section)

FYI: This is not new by any means. Porsche did this EXACT same setup in the 986 50Th anniversary car. Granted it was a Variocam Plus engine, but it was still a 3.2.

Something else.. scared of the larger throttle body? The rubber bellows from the MAF housing to the throttle body? They sell two versions. One for this 3.4 throttle body and one for the 2.7 cars (same one they used in the 50th anniversary 3.2 car)


B

[JAAY]

Sorry I have not updated. It has been in the car over a week and it is running flawless. No codes etc.... What is amazing to me is that the 987 air filter has to have at least 2 to 3 times more surface area. The thing is huge. It was a bit of a pain in the butt to get the piping to fit the way I wanted. Like you know I don't have a typical 2.7 or 3.2 so my plenum sits differently. I was able to cut up the IPD silicone pipe I had and use that with some t-bolt clamps and got it all to work with the BMW mass air housing I am running. Using a beemer one because it was cheaper than a cayman one and I didn't need the mass air sensor itself that comes with it. I have yet to put my wide band back in but I may do it this week. I will let you know if it is running any differently. I can assure you thought that it is running real strong. Schoir can vouch for that. Let me know if you have any questions.

J

[jaykay]

Sounds good yes I will have the same problem......my tb will pointing the wrong way! Be sure to snap some pictures next time you have the engine open

[barkinfool]

Bump

My favorite topic of past few months, but as a non-engineer, hard to figure where this ended up & decipher. I have a '02S & would like to know what is the best option for more performance without breaking the bank -- appreciate the insights throughout but still a bit over my head. Where have the knowledgeable folks ended up on this 987/Cayman air box? Is there a combo that makes most sense for the 986S crew for better performance than stock?

Bonus Q: In PA, not near Brad in LA area, so any shop near Pittsburgh that it would make sense to approach since probably beyond my limited skills?

[Kroggers]

Thank you for the clarification buddy...

[JAAY]

For all you with children you know how difficult this is. I had a about a 2.5 hour window while little Lily was sleeping this morning. So out to the garage with some tools and the baby monitor.

Recap - My motor is a 996 3.4 so not the nice bolt up situation because of the cable throttle body. So I had to do some extra slicing and dicing. Here are the photos so far. This is as far as I got until the baby monitor called me in for sandwich time.

Untouched


Planning my attack


First slice

[JAAY]

More cutting needed. The outer plastic around the main tube had to go, maybe didn't but It sure makes it a bunch easier to work with more space



After the extra was gone

[JAAY]

To catch you up to speed I did some preliminary test fitting. I removed the drivers side intake manifold and the fuel rail was removed also on that side. I probably not need to remove the fuel rail but I did. You will notice in the pictures to come that all the open ports were taped over and filled to keep the crap out while working in there.



After I fit the box in there I test fitted my mass air housing. I am using a bmw housing, talked about elsewhere. So being that is not a direct fit I chopped off the oem connection point on the air box tube and fitted a silicone coupler that was previously used on my IPD piping (for sale now) and secured it with a T-bolt clamp.

before

after

[JAAY]

I did clean up all the edges with the cutting wheel and a file so now they are all pretty. Sorry I didn't take a pic of that. I have not made a a patch piece for the muffler section yet. When I head out today I will pick up some apoxy and use a piece of the cut up box that is readily available right now on the floor of my garage.

In the car


Test fit of the maf. Still needs a clamp on the maf side.


This is where I am at for now. Maybe later on this evening after hours (baby sleeping) I will head back out and put the manifold and fuel rail back in.

Side note:

Anybody know if it is ok to reuse the injector o-rings? There in good shape, they were replaced when I put the motor in. If they are reusable, should I oil/lube them or anything?

Thanks for the info on that.



J

[alxxnova]

Is there a muffler in the 986 air box?

If so can it be blocked also?

Alex
01 Boxster S
08 Passat 2.0T
92 FXSTC

[Overdrive]

jmitch, I think what Brad was getting at was that the 2.7 has, over the years, gotten a bump in power from the factory without really being heavily modified. The latest iteration of the 2.7 was putting out around 240hp before they went to the 2.9, which is nearly the 250 that the Boxster S had back in 2000 with the 3.2. I'm sure it wouldn't take much to coax the rest of that power out of it when it's nearly there already. For that matter, I'm sure Porsche was simply undoing much of what they did to restrict the engine over the years to let a little more power out and keep pace with the 911's increases.

Unless he is talking about an earlier 2.7 that he has modded lightly to produce better numbers, in which case I second your question.

[AndyA6]

Any further updates?
TIA!

[The Radium King]

what do you guys think about this:

BGB / Fabspeed Cold Air Intake Install (with Pics) -

works for the cayman, so will work for the 986 as the chassis is the same in this spot (would require different silicone as the throttle bodies are in a different place). expensive, but could fabricate something real easy; do as another member did on this forum and use that rubber boot that is removed in the link above as a template to make the plate out of lexan, attach one of these:

RX-4750 - K&N Universal Air Filters, Universal X-Stream Clamp-On direct from K&N

and then 3" silicone to the maf housing (reuse the oem unit) and throttle body.

do you think there would be any issues with water, etc.?

[onaFLYer]

To think of all the trouble I went through to put in that airbox he cut in half....I think I'll leave mine as is now. Plus, It looks like a total PITA to get that new filter out to clean it.