987 v 986 Air box

[Newsguy]

I would also like to confirm the tune for a 2002 S: the 7.2 DME will work with the 996 tune?

[hotdawwgman]

So I was able to add the 987 Airbox, 987 MAF Tube, 997 Throttle Body, and T-Plenum in. All parts were slightly used, but looked decent. Fired her up. Drove her around for a tad, and now I have 3 codes. P1119, p1126, & p1133. I need a tune which should happen this week. Is it possible I need a new Throttle position sensor? Or should I try to do the throttle relearn procedure first?

[preppyr6]

For anyone looking for a 987 MAF housing adapter sleeve (3.25" OD 3" ID) I found this on eBay that might help. The pvc-welt link wont work for us US folks (AFAIK).

https://www.ebay.com/itm/16mm-200mm-PVC-Inner-Diam-Equal-Water-Supply-Pipe-Fittings-Adapter-Connector-/174808609002

Hope this helps someone. Im in the process of sorting parts for this upgrade now.

[Robert986]

Originally Posted by hotdawwgman

So I was able to add the 987 Airbox, 987 MAF Tube, 997 Throttle Body, and T-Plenum in. All parts were slightly used, but looked decent. Fired her up. Drove her around for a tad, and now I have 3 codes. P1119, p1126, & p1133. I need a tune which should happen this week. Is it possible I need a new Throttle position sensor? Or should I try to do the throttle relearn procedure first?

You don't need a new throttle position sensor, what you need is a tune with a updated MAF-table to reflect the larger MAF tube area.

[ike84]

Originally Posted by Robert986

You don't need a new throttle position sensor, what you need is a tune with a updated MAF-table to reflect the larger MAF tube area.

Hey robert! speaking of tunes, how is your car doing? Any updates?

[Robert986]

Originally Posted by ike84

Hey robert! speaking of tunes, how is your car doing? Any updates?

Hey Ike, thanks for asking! Car runs really great, just wish the summer was longer! Next mod will be coilovers I guess.. 😎

[ike84]

That's great to hear man!

Coilovers are phenomenal. My car has less than 40k when I switched over, and the OEM struts were toast. The coilovers made a truly remarkable difference in handling characteristics.

Sent from my SM-G970U1 using Tapatalk

[Robert986]

Btw, as stated previously I put in the 987 airbox & MAF with great results.. My tuner made a new MAF-table so if anyone needs a MAF table for the 987 MAF with Motronic 7.8 let me know!

[Coaster]

Originally Posted by preppyr6

For anyone looking for a 987 MAF housing adapter sleeve (3.25" OD 3" ID) I found this on eBay that might help. The pvc-welt link wont work for us US folks (AFAIK).

https://www.ebay.com/itm/16mm-200mm-PVC-Inner-Diam-Equal-Water-Supply-Pipe-Fittings-Adapter-Connector-/174808609002

Hope this helps someone. Im in the process of sorting parts for this upgrade now.

Initially, looking for a non-tune solution.

Does the 987 assembly come with a MAF sensor installed? I think that is what I understand.

I assume the 987 MAF and fitting comes off (with the special security bits) and the PVC sleeve slides in to reduce the ID to 3". A hole is needed in the reducer tube, and the 987 MAF and fitting is reinstalled? Assuming the 987 MAF assembly comes with a MAF installed, the connector plugs right in?

Later, I assume I can remove the reducer and push a 986SE tune on a 2003 986 S?

[Drewie]

One done also here

Used the best from from two posts:

987 v 986 Air box
from The Radium King and
987 v 986 Air box
from scottmaggie

We have started according to the instruction in The Radium King's post, but we didn't bend the engine lid tab.

Rather we lower the engine a little bit according to the instructions from scottmaggie.
But again 6" or 15 cm is impossible to lower, the hoses start to "dislike" it after 3" or 8 cm. We unscrewed only 4 bolts in the front mount of the engine. It was enough for me.
I can't imagine to insert the 987 air box there with the left air distributor still mounted.

Don't forget you need longer bolt as mentioned in step 17 in scottmaggie's instruction, and also insert the blue rubber grommet from 986 air box instead of the 987 black plastic grommet for tucker before trying to fit the air box.

We were able to fit the Air Mass Flow tube when the air box had been bolted. No need to mount it on the air box in advance.

The K&N filter was also little pain to fit.

The rest slightly differ to the other posts here since I was fitting GT3 throttle body not the 987 one. The T-shaped intake plenum and the elbow part was 3D printed. Designed by Ben006.
More info here:
Intake plenum and 911 throttle body

After all mounted and 3 times checked all is connected back, I turned key to position ON for approx. 1 minute. Then OFF for another minute.
Then with fingers crossed we started the engine. The engine was able to idle without engine light and any fault code in the ECU. Strange...
The AF ratio was definitely too high because the engine was "shooting" to the exhaust. Unfortunately our multibrand diagnostic tool was not able to start the basic adjustment of the ECU and engine components.
ECU started to learn at the third start when I didn't let the engine idle but rev it just under 2000 rpm.

After 5 minutes there was standing perfectly idling Porsche Boxster S 986 with 987 Air box with K&N filter, 987 AMF, silicone hump hose, custom 3D printed elbow, short silicone hose, GT3 Throttle body, custom 3D printed intake plenum, OEM air distributors and OEM 3,2l engine . In addition long exhaust manifolds, OEM CATs, and sport mufflers. At that time without engine light or any fault code in the ECU.

All took 12 hours. Everything in the engine bay is super tight, nearly no room for hands and tools. Many times we got stuck because the hose refused to connect back or were finding from which spot and which kind of wrench from wchich direction to use to screw some of the bolts.

BUT Engine light came up after ca. 50 miles / 70 km on my way to tuning company. No limb mode just orange engine light.
Unfortunately they were not able to dyno the car because even switched off PSM the car refused to rev over 4000 rpm without massive loss of power.
Need to find someone with 4x4 dyno which can rotate also front wheels during measuring.
So confused I forget to ask what fault was there. They just done small adjustment to "fix" this error.

No special tune so far...

Anyway looking for any Porsche specific diagnostic tool because readiness for emission test is still not green. So I don't believe to these multibrand diagnostic tools anymore. Because they probably show only emission relevant DTC not all of them.

[Pololo_Boxster]

Reviving this thread, if it's OK with members..

I am going to start doing this upgrade with my 2000 Boxster 986S..

So far I have the following:
1) 987.1 Airbox with the MAF section
2) 74mm TB from the 997
3) Plenum from the same 997

Still a bit confused if I either need to use the 987 MAF or the 986 MAF along with these upgrades?

If I go with the current 986MAF, do I need to have it tuned?

When do I need to have it tuned? if so, what's the best way to do this?

My apologies if this has been covered already... I read through all 16 pages, but still a few questions left..

TIA,
Regards
CB

[The Radium King]

is up to you.

first, some nomenclature.

the maf is the sensor. the 986 maf is the same as the 987 maf.

the maf housing is the tube the maf mounts to. on the 986 it is part of the airbox. on the 987 it is a separate tube that attaches to the airbox.

the 986 maf housing is a smaller diameter than the 987 maf housing. the computer multiplies the maf reading by the cross-sectional area of the tube to determine flow. so, change the tube diameter and confuse the computer.

if you do not wish to do a flash then saw the maf housing off of your 986 airbox and plumb it all together. the 987 maf housing is not required.

otherwise, if you plumb it all together using the 987 maf housing then you need a flash that will work with this larger diameter. for a 2000 the solution is a 996 flash. the 996 of the same year had the larger intake tract and the 3.2 runs just fine with this flash. your dealer should be able to provide for you, or anyone with a piwis or pst2 contraption.

the benefits of the latter option are twofold; using the larger diameter maf housing removes a restriction to airflow. second, the thinking is that porsche neutered the boxster so as to not compete with the 996. otherwise a 3.2 should not be 50 hp down on a 3.4. there's only 3 places that can happen - exhaust, intake, ecu (fuelling, timing). so, an ebay exhaust, clean up the intake as much as you can (pro tip - bolt an intake manifold from a 3.4 onto your car) and 996 tune.

Originally Posted by Pololo_Boxster

Reviving this thread, if it's OK with members..

I am going to start doing this upgrade with my 2000 Boxster 986S..

So far I have the following:
1) 987.1 Airbox with the MAF section
2) 74mm TB from the 997
3) Plenum from the same 997

Still a bit confused if I either need to use the 987 MAF or the 986 MAF along with these upgrades?

If I go with the current 986MAF, do I need to have it tuned?

When do I need to have it tuned? if so, what's the best way to do this?

My apologies if this has been covered already... I read through all 16 pages, but still a few questions left..

TIA,
Regards
CB

[Pololo_Boxster]

Thank you so much for the valuable information. You are right about getting my nomenclature right...

Usually picture a MAF as a pipe/sensor included as in my older bimmers... DIdn't know the MAF are was part of the 986 airbox.

Couple of questions please(actually 3 ) :
1) Any 996 tune will do it? I am sure there's a difference between the base and the S version.
2) I have the 997 TB/plenum (in combination with the 987 airbox). Do I need the 996 intake as well? Is that a must or a nice to have? Was planning on keeping the 3.2S intake intact.
3) Suggestion for the pipes/bends to connect from the airbox to the plenum?

Already got the exhaust, and downpipes (no secondary cats)... but keeping the stock headers/manifold due to the emissions regulations in my county.

Was planning on leaving my car stock (wishful thinking lol)... but I can never manage to do that with my cars.

Once again, thank you so much for your help and feedback.

Regards
CB

Originally Posted by The Radium King

is up to you.

first, some nomenclature.

the maf is the sensor. the 986 maf is the same as the 987 maf.

the maf housing is the tube the maf mounts to. on the 986 it is part of the airbox. on the 987 it is a separate tube that attaches to the airbox.

the 986 maf housing is a smaller diameter than the 987 maf housing. the computer multiplies the maf reading by the cross-sectional area of the tube to determine flow. so, change the tube diameter and confuse the computer.

if you do not wish to do a flash then saw the maf housing off of your 986 airbox and plumb it all together. the 987 maf housing is not required.

otherwise, if you plumb it all together using the 987 maf housing then you need a flash that will work with this larger diameter. for a 2000 the solution is a 996 flash. the 996 of the same year had the larger intake tract and the 3.2 runs just fine with this flash. your dealer should be able to provide for you, or anyone with a piwis or pst2 contraption.

the benefits of the latter option are twofold; using the larger diameter maf housing removes a restriction to airflow. second, the thinking is that porsche neutered the boxster so as to not compete with the 996. otherwise a 3.2 should not be 50 hp down on a 3.4. there's only 3 places that can happen - exhaust, intake, ecu (fuelling, timing). so, an ebay exhaust, clean up the intake as much as you can (pro tip - bolt an intake manifold from a 3.4 onto your car) and 996 tune.

[Pololo_Boxster]

Thank you so much for the valuable information. You are right about getting my nomenclature right...

Usually picture a MAF as a pipe/sensor included as in my older bimmers... DIdn't know the MAF are was part of the 986 airbox.

Couple of questions please(actually 3 ) :
1) Any 996 tune will do it? I am sure there's a difference between the base and the S version.
2) I have the 997 TB/plenum (in combination with the 987 airbox). Do I need the 996 intake as well? Is that a must or a nice to have? Was planning on keeping the 3.2S intake intact.
3) Suggestion for the pipes/bends to connect from the airbox to the plenum?

Already got the exhaust, and downpipes (no secondary cats)... but keeping the stock headers/manifold due to the emissions regulations in my county.

Was planning on leaving my car stock (wishful thinking lol)... but I can never manage to do that with my cars.

Once again, thank you so much for your help and feedback.

Regards
CB

[The Radium King]

not sure if there was an 's' version of the 996 (at least in 2000 anyways). regardless, all 996 used the same tune.

the 997 (or 996) intake plenum (the 'tee') will fit on the boxster 3.2 intake. it is the same width but a slightly larger diameter - i was able to stretch the rubber boots to fit no problem.

what bends, etc. you use would depend on whether you are using the 986 or the 987 maf housing.

if you are going with the 986 unit i've got the assembly off my car i could probably part with (ie, when i did the airbox and tb/plenum but hadn't done the tune yet).

[Pololo_Boxster]

Originally Posted by The Radium King

not sure if there was an 's' version of the 996 (at least in 2000 anyways). regardless, all 996 used the same tune.

the 997 (or 996) intake plenum (the 'tee') will fit on the boxster 3.2 intake. it is the same width but a slightly larger diameter - i was able to stretch the rubber boots to fit no problem.

what bends, etc. you use would depend on whether you are using the 986 or the 987 maf housing.

if you are going with the 986 unit i've got the assembly off my car i could probably part with (ie, when i did the airbox and tb/plenum but hadn't done the tune yet).

Thank you. Do you mind if I send you a PM?

Regards,
CB

[Nitro V8]

Originally Posted by The Radium King

not sure if there was an 's' version of the 996 (at least in 2000 anyways). regardless, all 996 used the same tune.

the 997 (or 996) intake plenum (the 'tee') will fit on the boxster 3.2 intake. it is the same width but a slightly larger diameter - i was able to stretch the rubber boots to fit no problem.

what bends, etc. you use would depend on whether you are using the 986 or the 987 maf housing.

if you are going with the 986 unit i've got the assembly off my car i could probably part with (ie, when i did the airbox and tb/plenum but hadn't done the tune yet).

Hi
Did you eventually go with the 987 maf tube and tune? If so did you see a performance hp gain over the 986 maf tube?
Thank you

[The Radium King]

Originally Posted by Nitro V8

Hi
Did you eventually go with the 987 maf tube and tune? If so did you see a performance hp gain over the 986 maf tube?
Thank you

i did install the 987 maf tube and push a 996 tune onto the car. it sure felt like performance improved not nothing quantifiable. my thought exercise was that the hp difference between a 3.2 and a 3.4 was too large to be just due to displacement. intake, exhaust, and tune are the only other variables as the heads and bottom ends are the same. so, i improved intake and exhaust and put a 996 tune on it. all the porsche rats at the track think i am running a 3.4 and i can chase 987 spyders around pretty easy.

[Nitro V8]

Thank you for the reply.

I have looked at the 987 airbox and before the maf but after the filter there is a 90 degree turn that constricts air flow to less than the 83mm id of the 987 maf tube. Difficult to judge exactly what it is due to its angle and turn but I would suggest around 70mm.

With the above in mind what is the point of the larger 987 maf tube over the 986 maf tube? All that is happening is that the restriction is moved closer to the air filter.

Any thoughts/comments?

[The Radium King]

every time you compress air (force it through a narrow opening) you do work. and heat the air. i would rather do less work and have cooler air.

but make your own choices. to quote yoda - do or not do.