Intake/Exhaust Upgrades for a 2003 3.2 S

[drumboxer]

Hey everybody, I am new to the forum and new to my Boxster S (had a '99 previously and loved it). I have been reading feverishly through posts about upgrading intake and exhaust to get more power out of my 3.2. This is primarily a street car, but will be used at the track 3-4 times a year. I also have several other mods going on (RSS pulley, deep sump, IMS, safety bits, etc.), but am really just focused on intake/exhaust at the moment.

The list of parts I am starting with is here, and I have a few questions:

- OEM 996 Intake, Throttle Body, and Plenum
- OEM 987 Air Box, MAF, and Filter
- Aftermarket Headers, Test Pipes, and Muffler/Exhaust

Questions:

1) I have read some posts where users said they needed to use a 987 Cayman engine cover in order to get clearance. Other users said you can simply cut the "muffler" off of the 987 air box in order to make it fit in a 986. My question is, with the intake set-up above, what will I need to do to make it fit?

2) I have seen posts with positive reviews of exhaust parts from both TopSpeed and Manzo (M2). Both are inexpensive (and therefore appealing) options next to the big names at Fabspeed, etc. I have noticed that the header+testpipe+muffler combo from TopSpeed is now nearly double the price ($1200 vs. $600) of the same set-up from Manzo (both are on ebay). Is anybody familiar enough with both set-ups to talk about the difference? What am I getting for the extra $$$ at TopSpeed?

3) Lastly, what do you recommend for tuning the ECU once this modification is done? I am used to playing with much older cars, and am completely unfamiliar with this process. I have seen several places that ask you to list out your mods and send your ECU in by mail, others that offer a tuned product you can buy, etc. Any recommendations? I am located in Indianapolis, IN, btw, in case there is someone you know of locally.

THANK YOU!!!

[KRAM36]

Originally Posted by drumboxer

Hey everybody, I am new to the forum and new to my Boxster S (had a '99 previously and loved it). I have been reading feverishly through posts about upgrading intake and exhaust to get more power out of my 3.2. This is primarily a street car, but will be used at the track 3-4 times a year. I also have several other mods going on (RSS pulley, deep sump, IMS, safety bits, etc.), but am really just focused on intake/exhaust at the moment.

The list of parts I am starting with is here, and I have a few questions:

- OEM 996 76mm Throttle Body only, and USE a 997 Distribution T to your stock Plenums
- OEM 987 Air Box, MAF, and Filter You will need to push a tune from a 996 of the same year as your car using the 987 MAF housing.
- Aftermarket Headers, Test Pipes, and Muffler/Exhaust

Questions:

1) I have read some posts where users said they needed to use a 987 Cayman engine cover in order to get clearance. Other users said you can simply cut the "muffler" off of the 987 air box in order to make it fit in a 986. My question is, with the intake set-up above, what will I need to do to make it fit? No need for the engine cover as long as you stay with your stock plenums.

2) I have seen posts with positive reviews of exhaust parts from both TopSpeed and Manzo (M2). Both are inexpensive (and therefore appealing) options next to the big names at Fabspeed, etc. I have noticed that the header+testpipe+muffler combo from TopSpeed is now nearly double the price ($1200 vs. $600) of the same set-up from Manzo (both are on ebay). Is anybody familiar enough with both set-ups to talk about the difference? What am I getting for the extra $$$ at TopSpeed? Get Circuit Werks cat delete pipes they are the best. Currently out of stock is why the price is so high. They are normally $189.99 Circuit Werks Porsche Boxster 986 00 04 2 7 3 2 Test Pipe Cat Delete Testpipe TP | eBay My pick on the muffler would be Borla Borla Exhaust System for 00 04 Porsche Boxster s Boxster Roadster s 3 2L 140115 | eBay

3) Lastly, what do you recommend for tuning the ECU once this modification is done? I am used to playing with much older cars, and am completely unfamiliar with this process. I have seen several places that ask you to list out your mods and send your ECU in by mail, others that offer a tuned product you can buy, etc. Any recommendations? I am located in Indianapolis, IN, btw, in case there is someone you know of locally. You will need to push a tune from a 996 of the same year as your car using the 987 MAF housing.

THANK YOU!!!

Modified in your quote.

Another good move. Get these clamps to connect the Circuit Werks cat delete pipes to the Borla muffler. http://www.verociousmotorsports.com/Shop-by-Brand/Torca/EasySeal-Exhaust-Clamp-Stainless-Steel

Borla exhaust

[eicheldp]

Originally Posted by drumboxer

2) I have seen posts with positive reviews of exhaust parts from both TopSpeed and Manzo (M2). Both are inexpensive (and therefore appealing) options next to the big names at Fabspeed, etc. I have noticed that the header+testpipe+muffler combo from TopSpeed is now nearly double the price ($1200 vs. $600) of the same set-up from Manzo (both are on ebay). Is anybody familiar enough with both set-ups to talk about the difference? What am I getting for the extra $$$ at TopSpeed?

THANK YOU!!!

I have a 2004 S that I am also in the midst of modding to get more HP & performance. I just purchased a set of test pipes and was going to go to Fabspeed, but they were $595. A friend on this forum turned me on to Top speed, who offers discounts to forum members.
Test pipes are ordered and in transit. The people at Top Speed have been great!

http://986forum.com/forums/boxster-parts-sale-wanted/33153-f-s-che-boxster-test-pipes.html

[tommy583]

Originally Posted by KRAM36

Modified in your quote.

Another good move. Get these clamps to connect the Circuit Werks cat delete pipes to the Borla muffler. EasySeal Exhaust Clamps: Torca EasySeal Clamps in Stainless Steel for Lap Joint Connections

Borla exhaust

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[edc]

If you are doing the larger throttle body then you will need a different airbox to TB intake. I made one up along these lines http://www.boxa.net/forum/index.php?showtopic=53075&page=9#entry685186

[KRAM36]

Originally Posted by edc

If you are doing the larger throttle body then you will need a different airbox to TB intake. I made one up along these lines http://www.boxa.net/forum/index.php?showtopic=53075&page=9#entry685186

I'm running the stock 986 MAF housing and using the stock 986 piping to the 76mm TB as I don't want to do a tune on my car just yet.

Pics will be coming soon.

Once I get the headers, cat delete pipes and Borla muffler, then the tune will come along with using the larger 987 MAF housing and larger piping to the TB.

[edc]

The standard intake pipe that fits over the 68mm TB won't fit over the 75mm TB so you will need to get creative.

Edit - not only that but when you mate to the 996 plenum T the shapes are different so the TB points in the wrong way to use the standard intake piping.

[KRAM36]

Originally Posted by edc

The standard intake pipe that fits over the 68mm TB won't fit over the 75mm TB so you will need to get creative.

Correct, however the OD of the part that goes over the TB is 80mm which is the same size as the OD of the 76mm TB. So you just have to use a 80mm ID silicone tube to connect them. I've also reenforced the thin wall of the stock pipe.

[KRAM36]

Originally Posted by edc

The standard intake pipe that fits over the 68mm TB won't fit over the 75mm TB so you will need to get creative.

Edit - not only that but when you mate to the 996 plenum T the shapes are different so the TB points in the wrong way to use the standard intake piping.

To your edit. I'm using a 997 Distribution T and yes they do not mach up. That is where you use a 90° 80mm silicone tube.

http://www.ebay.com/itm/Racing-Silicone-Hose-Elbow-Coupler-Pipe-3-15-to-3-15-90-Degree-ID-80-mm-Black-/141439976411?pt=Motors_Car_Truck_Parts_Accessories&hash=item20ee7ac3db&vxp=mtr

[edc]

Yes - I made a whole new intake in from airbox to TB as I linked to, just trying to help out the OP.

[KRAM36]

Originally Posted by edc

Yes - I made a whole new intake in from airbox to TB as I linked to, just trying to help out the OP.

I have a very specific reason to stay with the stock piping. I have a Tiptronic transmission and there is a hose that goes from the trans to the stock piping. I just wanted to let people know you can still use the 986 piping. I have worked this out and you can use the stock piping. I've put a lot of work into this setup. Even made it to when I decide to go with the larger MAF housing all I have to do it unclip my current MAF housing and clip the 987 MAF housing right into the 987 air box like it is from the factory.



So I have to keep the stock piping until I figure out how to get the hose incorporated into a larger piping setup.

BTW: Your link doesn't work for me.

[drumboxer]

Thank you for all of the great input!

1) So I have a complete intake from a 996 - Don't I want to use the plenums/complete intake from that set-up for increased flow? Am I understanding correctly that this mod is what will require the 987 lid?

2) edc - I cannot get your link to work, but would love to see how you get air from the 987 box to the 996 TB. KRAM - are you saying that this can be accomplished by just using a silicone tube?

3) KRAM - When it comes to engine electronics, I read at a kindergarten level: How does one "push a 996" tune? Also, my car is an '03, my 987 air box is an '05, and my 996 intake is a '99. Which year 996 tune do I use and how do I account for the 987 box/MAF?

[KRAM36]

From what I've read, yes you will have to use the 987 lid.

Yes you can go from the MAF to the TB using silicone tubing couplers.

You would use a 2003 996 3.4 tune. You would have to have someone push the tune for you.

[edc]

You might have to register to view but there are plenty of my pics and parts used and dimensions there. This was on my first 986 S. It was really no more than a straight piece of pipe and 2 silicone bends with some judicious shaping and cutting. This went from 986 airbox to 996 TB. but you could use the same approach if it was 987 airbox. It then attached just like the original intake by nipping up a couple of jubilee clips.

[The Radium King]

so, just to get my terminology straight, and working from out to in, you have:

snorkel
air box
maf and holder
intake pipe
throttle body
plenum
intake manifold

from what I gather (haven't done this, but some have) the 996 intake manifold will fit on the 986 motor, however it (a) is taller and requires the 987 engine cover, and (b) only has two of the six fastening points match on each side. as a result, you have to (a) tap two holes on each side, and (b) fabricate two brackets on each side.

re the tune, it is required only if you change the diameter of maf holder (different diameter means different air readings to the computer). ie, if you use a 987 maf holder to match your new air box then you need to retune you engine as it is a larger diameter than what the computer expects. you can reuse the maf holder currently in your car by sawing it off your old air box, or find a bmw unit (or any car that runs a bosch system) of the same inside diameter; this way don't have to do anything with the computer.

the design of the intake pipe from the maf holder to the throttle body will depend on your decision on what you are doing with the maf holder. I reused by original maf holder and was able to get away with reusing the old intake tube and getting a 90 degree reducing elbow to mount on the throttle body (the inside diameter of the new throttle body is 3" but the outside is 3.25" due to the thickness of the lip - you want an elbow that reduces from 3.25" to 3"). probably the best approach is to get the manifold/plenum/throttle body on, and the air box and maf holder in, then figure out what you need to get the two to join. if you want a super duper oem look, then IPD make a pipe for the cayman that should do the job (the IPD plenum is about the same dimensions as the 997 plenum, so should fit right up provided you take the 987 maf holder route).

[drumboxer]

Ok, you guys are awesome. Please take a look at my notes/questions below:

Originally Posted by The Radium King

so, just to get my terminology straight, and working from out to in, you have:

Thanks for clarifying, I want to be sure I am on the right page: Here is what I was planning to use:

snorkel - part of the airbox? If so, 987
air box - 987
maf and holder - 987
intake pipe - Sounds like I need to fabricate one? (I have a manual trans btw)
throttle body - 996
plenum - 996
intake manifold - 996

from what I gather (haven't done this, but some have) the 996 intake manifold will fit on the 986 motor, however it (a) is taller and requires the 987 engine cover, and (b) only has two of the six fastening points match on each side. as a result, you have to (a) tap two holes on each side, and (b) fabricate two brackets on each side. Thank you, this is helpful. I am planning to use the 996 manifold, so I guess tapping new holes will be necessary.

re the tune, it is required only if you change the diameter of maf holder (different diameter means different air readings to the computer). ie, if you use a 987 maf holder to match your new air box then you need to retune you engine as it is a larger diameter than what the computer expects. you can reuse the maf holder currently in your car by sawing it off your old air box, or find a bmw unit (or any car that runs a bosch system) of the same inside diameter; this way don't have to do anything with the computer. If I have to send the ECU away to retune anyway, would I be better off with a custom tune that accounts for my motor and each modification made?

the design of the intake pipe from the maf holder to the throttle body will depend on your decision on what you are doing with the maf holder. I reused by original maf holder and was able to get away with reusing the old intake tube and getting a 90 degree reducing elbow to mount on the throttle body (the inside diameter of the new throttle body is 3" but the outside is 3.25" due to the thickness of the lip - you want an elbow that reduces from 3.25" to 3"). probably the best approach is to get the manifold/plenum/throttle body on, and the air box and maf holder in, then figure out what you need to get the two to join. if you want a super duper oem look, then IPD make a pipe for the cayman that should do the job (the IPD plenum is about the same dimensions as the 997 plenum, so should fit right up provided you take the 987 maf holder route). - And if I intend to use the 987 MAF holder? My understanding is that this is optimal so as to not create a bottleneck with the smaller diameter 986 housing.

[BrokenLinkage]

But does the 550 SE have a special tune to reflect the use of the 987 airbox & maf/holder? If so, can this tune be used with a five chain engine (ie my 2001s)?
It then uses the same throttle body diameter as any other S, with the same plenum & intake manifold as stock?
Am I correct in thinking there is not much benefit in reducing the restriction in one part of the intake, if it is left in place elsewhere? (Like the rate-limiting-step in chemistry). So if I am not on board with drilling new mounting points and installing the 996 intake manifold, with the attendant use of the 987 engine cover and loss of the rear shelf speaker bar, then this is pretty much a waste of time?
Or can I pick u a few horses just using the 987 airbox, modded to fit the stock MAF, plus a larger throttle body, without a retuning of the ECU?
Thanks everybody for sharing your knowledge with those of us lower on the ladder of flat six enlightenment.

[KRAM36]

The 2004 Special Edition cars that used the 987 air box were tuned by Porsche for those parts. I believe they still used the stock 986 TB and back. The Special Edition cars only had a 6 hp gain over the standard 3.2 motor of the 2003 and 2004 models.

[BYprodriver]

Originally Posted by BrokenLinkage

But does the 550 SE have a special tune to reflect the use of the 987 airbox & maf/holder? If so, can this tune be used with a five chain engine (ie my 2001s)?
It then uses the same throttle body diameter as any other S, with the same plenum & intake manifold as stock?
Am I correct in thinking there is not much benefit in reducing the restriction in one part of the intake, if it is left in place elsewhere? (Like the rate-limiting-step in chemistry). So if I am not on board with drilling new mounting points and installing the 996 intake manifold, with the attendant use of the 987 engine cover and loss of the rear shelf speaker bar, then this is pretty much a waste of time?
Or can I pick u a few horses just using the 987 airbox, modded to fit the stock MAF, plus a larger throttle body, without a retuning of the ECU?
Thanks everybody for sharing your knowledge with those of us lower on the ladder of flat six enlightenment.

Yes the 550 has a special tune & a 7.8 DME so you must have the 7.8 DME to use it.
T/B & plenum are standard size.
I believe the larger intake hose will help even with a slight diameter reduction midway.
You can install the whole 996 intake manifold & lower the engine mounts for clearance.
987 airbox will flow roughly double the amount of air as the 986 airbox, + any other enhancement parts. DME must be programmed with correct MAF tube diameter in order for MAF to calculate intake air volume. If diameter stays the same reprogramming is not required.

[The Radium King]

the 2005 uses a 7.8 version of the computer so won't work with a 7.2 computer (ie, what was in the cars before 2002).

while staying with the old maf housing (and the associated restriction) isn't perfect, the 987 air box is a very big improvement over the 986 unit. the 997 plenum is a very big improvement over the 986 unit, and the larger throttle body, at the very least, improves throttle response (power comes an earlier in pedal travel).

regarding the question of tune, i'd assume that an aftermarket tune is the best, and there are a variety of options out there. at the least, running with an oem tune from a car with a larger maf housing (pre 2002 e-throttle 996) is the less expensive solution (1/2 hour of shop time vs $600 to $1000 for custom) and gets you what the 996 guys get.