981 2.7 (base) exhaust tip upgrade on a 987...

As a breakout thread from @dasschild 's fun " Best Mod Under $500? thread , I was amazed to have missed the hack that one can apparently bolt on a 981 2.7L (base) exhaust tip on a 987 for both more rumble and easier flow. Wow! Assuming the 981's base exhaust offers a wider pipe diameter in either the 987.1/987.2, of course -- there'll be better flow -- which is a good thing! The 987.2 base pipe seems really restrictive, whereas the 981 pipe looks like it offers a much wider throat than stock. As some of you guys know, as I enjoy my 987.2 for long-distance driving, I needed to revert to the quieter OEM stock exhaust as I have moderate tinnitus. But I really want a little bit more noise if I can get it. Per a brief background discussion here: the single (base) 987/981 tip appears on the 987/981 base models, and I've heard it referred to (mildly deridingly) as a "guppy mouth". Lots of drivers upgrade to the dual "T" tip of the S versions, which IMHO looks much better aesthetically but apparently offers minimal performance improvement gains over base. Finally, for more cash, many opt for aftermarket X-flow tips, which apparently helps increase flow -- but actually may quiet the snap/crackle/pop thing (which I love). With the standard "T"-style output on both the base and S models -- you have the pulses colliding with each other before exit -- which apparently equates to slower flow and more noise. Anyhow, a huge thanks to both @Stumpalump and @Ric_in_RVA -- I decided to immediately jump at it before this potentially awesome secret got out. So, I ordered a relatively inexpensive one on eBay per their suggestion. Strangely enough, the only inexpensive one in good shape available today was from the UK -- with shipping more expensive than the actual tip. Surprisingly, most all of the US-based ones up for sale were well north of $100 alone. I'm looking forward to installing it sometime this year (post surgical recovery) and give it a listen. Again, I have no idea how I missed this mod! Questions for @Stumpalump and @Ric_in_RVA : @Ric_in_RVA -- When you say drilling off the "right-hand" side clamp, which exact weld are we talking about with respect to the car's orientation? I figure... ask twice and grind off once. Here's a pic of the one that I just bought on eBay. The seller didn't include a photo of the top side that shows the welds. In the picture, which number (1 or 2) is the bolt that is connected to the weld that needs to be cut? I'm assuming that you said the "right side", when looking at the back of the car, you mean #2 aka the right/passenger side of the car when installed? Is the idea to just cut that weld, just so the clamp can spin freely and simply positioned out of the way? Clearly this was on the 987.2, but can we confirm this works on a 987.1 as well? Thanks again for sharing this mod, guys! Looking forward to hearing how this sounds.

Passenger side USA car. Weld is about 1/2 inch long and simply holds that clamp in a position that the bolt and clamp fouls the mount attached to the rear of the transmission. That tubing will scotch brite and wd40 to a nice matte shine and you can polish the SS tip right up. The whole system will actually clean right up with scotch brite pads or wheels...but easier done off the car.

Dynamite! Thanks for clarifying @Ric_in_RVA -- Ask twice, Dremel once. I'm familiar with the clamp on the 987.2 base tip and figured it was similar as those have two welds that flank the T-connector piece. Polishing first sounds like a great idea. In fact, I did some light exhaust polishing last fall with 0000 steel wool and Ospho® (phosphoric acid) and that seemed to do a great job. The 981 tip that's arriving from the UK appears to be in pretty good shape, but I'd like to get it over the finish line before mounting it onto the car.

The left clamp will hit the bracket that is mounted to the back of the transmission unless you rotate it or turn it 180. You can fit it on but it will rub and make alignment of the tip hard. Best to grind that tiny weld off before your pulling it all apart again. I painted mine flat black with header paint. Usually that type paint is burnt away but since the tip has a cover and out in the cool air my paint still looks new. The used price on these tips should be $75-125. If not available then wait until more pop up. Also don’t forget to drill or punch out the baffle by going in from the crossover tube. That is the chamber that the inlet dumps the exhaust into. Drilling that baffle lets the fumes get back to the pipe that exits the muffler easier. The pictures I found online of a cutaway muffler show two baffle walls. My 09 base only has one perferated wall in it. There is your porsche freer flowing cat back and it is dirt cheap. Dirt cheap and Porsche In the same sentence? That may be a first. 😀

Both clamp welds ground off and flipped over and rotated to the top.

A belated follow-up on this hack. Thank you guys, as ideally I'm on the right track with this. A few months back , I found an okay deal on one from the UK that was like 20 GBP, but the shipping and everything wound up being about 80 USD in the end. It was already pretty clean, and I finished cleaning it up. The damage that was there -- nobody would see the damage. As far as installation goes, it was a major delay due to a surgery, but I popped it on this afternoon while swapping over from my winter tires . In order to get it on there, I had to do a few things: 1) Cut both welds of the clamps (not a big deal with a hacksaw) - one didn't seem to be enough, so I pulled it off and put it back on with both welds cut. Thankfully, I lubed everything up with silicone grease, which made sliding everything on/off a breeze -- just as I did last fall when I reverted the exhaust to stock. 2) Loosened all bolts as expected at the center 3) Removed the 4 bolts/nuts that connect the muffler to the hanger 4) Loosened the 3 bolts on the driver's (L, aka port) side at the exhaust manifold -- which finally gave me wiggle room to slide the original one off and the new one back on. Easy to do with removal of the left rear tire and the plastic cover (2x plastic nut, 1 Torx). It took me a lot longer than I thought it would, as I did need to loosen the right side partially so I could slide the 981 exhaust on. Anyhow, here's where things wound up being pretty funny. After it was all set, I figured - let's go for an evening drive on I-93 and open her up. I started the car, and thought - it seems a VERY mild change. Maybe I can hear a little bit deeper rumbling? Okay, for 80ish bucks, I'll take it I guess. Well, the story isn't over. I'm in stop/go city traffic, and someone sounded ever so slightly uneven. Figured it was just the mod. But the time I hit the freeway entrance ramp (after about 15 minutes of stop/go traffic), I'm like -- this is sounding pretty good. Another 10 minutes of highway driving, it's sounding fantastic! But another 5 minutes later, I pull off to go turn around -- and I'm realizing -- this is just way too loud. Kind of like the original straight pipes that first came on the car. By the time I get home, it's clear to me that something isn't right and I had to laugh. For a moment there, I really thought that this upgrade would be significant -- yet not sounding like straight pipes. I'm guessing that the driving and heating up expanded the 4x clamps at the center, especially with the silicone grease on there. Tomorrow, after it's all cooled down, I'll check those four spots and will hope for the best. I seriously doubt there's a major leak at the left exhaust manifold, but I'll put it up on the lift if the rear four bolts don't cure it. Again, I had to laugh about it -- and it was indeed nice to have the summer tires back on the car -- especially after a long winter and nearly two months of recovery. Definitely one of those -- don't worry -- it's reversible (I didn't drill any baffles or anything) -- and it likely just needs some careful going over to find the leak. Cheers.

Here's the update. Tightened up all four center clamps this morning. No change! Uh-oh... As far as problem solving goes, I'm guessing that the sound became perceptively louder over 20 minutes, something must have become progressively loose. (Now I'm second-guessing myself?) Time to put the car back on the lift, remove both wheels and those two small plastic panels, and inspect the junctions/flange at the intake manifold. Maybe one or both jostled loose when trying to refit the muffler? @Stumpalump and @Ric_in_RVA -- It should be a little deeper of a rumble, but it should sound sorta close to stock, right? Trying to figure out what might be going wrong here. I indeed hacksawed the two spot welds (didn't grind them off), but left them in place as cut so the clamps could rotate but not push inwards towards the exhaust tips. Basically, they serve as stop tabs. Thanks!

I would say it’s a tone change primarily. Very slight if any sound increase. Even when I run my crossover pipe slid over it isn’t loud. I bet you ve got a leak at the header/ exhaust connection.

@Ric_in_RVA - Just reading your note post-wrenching today, and you are absolutely correct. When jostling the exhaust to put things back together the first time, it jostled the flange connection at the exhaust manifold. Those three studs on the starboard side are likely on their way out, and I'll likely have them pressed out the next time I have to remove the exhaust and will swap in 13mm bolts. I think I'm going to go back in there today and pop on a second set of brass nuts with Loctite so they don't accidentally back off again. Now that it's all corrected, my first impressions is that it's a very mild mod -- but worthwhile at ~$80. For those of us who aren't attuned to what our cars sound like, one wouldn't notice a difference. In my case, I could barely pick up just slightly more bass and it sounds less tinny than stock. I also want to say that when hammering down on the gas, it feels like the car is breathing better? No snap/crackle/pop but that's not to be expected. My guess is that it's behaving like if I popped in a X-pipe on the OEM exhaust. It's subtle, but I think it's worth it. Definitely quiet enough for long drives. Now that I know what's going on, I am half tempted to mess around with the crossover pipe as that's easy to access without putting it on the lift! ​ ​ @Ric_in_RVA - I think I get it per the mod. You slide the crossover (upper pipe) to the left, but how much of a gap is there? Just something super-slight, like the width of a jumbo paper clip (~1mm)? Also, how much of the crossover's circumference is closed off by the beer can? Just trying to gauge the leak's size. From what you're saying, it sounds like your front/top is closed off, so that would make it 50% of the circumference? Clearly my accidental leak I had was pre-muffler, so ideally this gap shouldn't be that loud. Thanks, Ric.

Glad you got the manifold leak fixed. If those studs are rusty and air hammer and air chisel are your friend. I have about a half inch gap but half the circumference is closed with the beer can baffle. Basically top and forward are blocked.

Oh, cool! Thanks for the rocket-fast reply, @Ric_in_RVA ! Really appreciate it. Just came up from the garage and got the car off the lift (QuickJack). Yeah, totally!. I got lucky that I didn't have to seriously battle those nuts when I first got the car a few years back, but the remaining threads weren't in great shape -- hence my having to have the port side drilled out. I very carefully chased those stud threads, but as we all know -- it's removing a very slight amount of metal and that makes the stud too loose. Just went back in for the starboard side, retightened the 3x brass M8 buts that I had put in there last year, and then just popped on 3x more additional nuts with some blue Loctite behind them so each one wouldn't back off via vibration. Before I go source a beer (or soda pop) can, a full 1/2" gap with a 50% circumference block is neither too loud nor droning? Just can't afford to annoy my neighbors with whom we share a wall. Psyched to give it a shot.

Update : No beer/soda cans available, but it turns out I had a heavy-duty recyclable aluminum roasting pan, which held a whole mess of awesome takeout BBQ from the other night. Figuring it's roughly the same thickness as a beer can, I cut out a roughly 75mm x 125mm rectangle -- which covers about 3/4 of the diameter (from notch-to-notch in the crosspipe). I left the gap open about 1/4" wide, with the bottom quarter exposed to help drain out condensation. Again, I went more conservatively on the initial openings as to not potentially upset my city neighbors. Will follow-up after some road testing. Again, FYI -- this is on my 987.2 2.9L -- all of which is very much downstream from the secondary cats (there are none in the 987.2 exhaust).

I think you will be good with it.!!

Thanks, @Ric_in_RVA ! So, here's the scoop after a few hours of test driving (~50 miles) on both freeway and backroads, with both the 981 exhaust mod AND the aforementioned crosspipe. First, I can confirm that this is a very, very easy doable mod, that took me maybe a half hour tops - as I was trying to be precise with my measuring and all that. It is stupidly easy to install and remove. No drilling, no futzing, no nothing. 2x 15mm bolts for the 981 exhaust clamp, 2x 13mm bolts for the crosspipe clamps. Next, I can attest that the car stays well within "not annoying the neighborhood" range, which is awesome. As I said before, I think the 981 tailpipe pronounces the bass note just slightly, which is cool. It's a very minor tweak but is better than nothing. With the crosspipe intentional gap setup as I put in there, I did get slightly more volume throughout the bands. But given that I personally have tinnitus, and I'm already pretty sensitive to sound stuff, the drone at about 2800 rpm was bothering me a bit and I don't think I'd enjoy it for long trips. It wasn't deafening, but it was kinda buzzy/annoying I guess. However, thankfully this is all totally subjective and it might not bother other people at all. I personally think I'm going to play around with it a bit more, given it is so adjustable. I think my next step will something akin to closing the gap, but just leaving the right clamp really loose. This way, there'll be just a sliver of a gap where some bark could push through but ideally no drone. If I do, I'll report back with my results -- and if anything did work well. So given that this is both so easy and quickly reversible, and one doesn't have to jack up the car, I'd recommend that anyone with OEM pipes give it a shot and see if they like it. A huge thanks to @Stumpalump and @Ric_in_RVA for this!

And the pipe cools off surprisingly fast. Keep the right size wrench and you can change it if you have a long drive to quiet or open for an afternoon of fun. I toy with designing one that could just rotate with no tools.

Same idea here, @Ric_in_RVA - Was thinking about some sort of rotational item too! Tentative update here in my quest to find a favorite setting -- as clearly the drone was too loud with the 1/4" gap and 1/4 open for my tinnitus ears. So, I went back in and completely removed the foil. If you completely slide the connecting pipe to the left, you'll see on the right that each side of both exhausts have two small notches in them that align with each other. So, I did a super-conservative setting by closing the gap where only the two notches on the right exhaust pipe are just barely exposed. So basically, we're talking roughly two semicircular holes barely the size a paper hole punch. It's not much, but at least it's not totally sealed off and I think you don't need much to allow noise to slip through. I did tighten down the right side, but I don't think as tightly as the left -- especially as there's nothing for the crossover piece to grip onto - but at least it won't rattle around. Well, I was stuck in terrible stop/go traffic for about 45 minutes this AM, but the combo of the 981 tailpipe and the tiny crossover holes seems really promising. Definitely sounds sportier than I remember stock being, and there was nothing annoying to my ears which is great. I did notice a bit of unevenness when idling at a standstill at about 1800 rpm, but remember that the crossover is there to equalize pressures between the two exhausts -- so this could be a factor. Definitely picking up some raspy/barky stuff in the 2K rpm range and 3800K rpm sounded kinda glorious. Hoping to take it out on the highway soon to see if the 2800 rpm drone is gone -- as that's key for my ears. I wouldn't be surprised if the improved sound (largely pronounced bass) is from the 981 exhaust and the treble raspiness and bark is from the crossover. Will report back after highway tests in the field.

Final note for now, after a reasonable mix of highway and side-road testing this past week. Short of super-long trips, I think I've squarely hit on the perfect setting. The 981 trip, PLUS exposing just the two half-moon notches on the edge of the right exhaust pipe) seems to allow plenty of character while largely eliminating the loudness of the 2800 rpm drone. Again, 3K-4K sounds fantastic. There's a strong possibility that the two half-moon notches may do next to nothing, but I don't really want to go back in there to futz with it as of right now. When I take my next long trip (say, 1K+ miles), I'll quickly go in there pre-flight and close the gap and see if I notice any difference whatsoever. I wouldn't be surprised if the sound is just from the 981 tips. Again, there's no crack/snap/pop with these mods but my tinnitus-prone ears are happy with it -- and it seems to add enough character to add to the overall enjoyment. If anyone is reading this and plays around with "quick-release" mods (so one could easily go from "mild to wild" for an afternoon), please post here as I'd be very interested. Cheers!

Just wanted to add a little to this thread as it inspired me to get the 981 tail pipe. No clear reason why other than it just seemed like a fun/cool idea. On the plus side, the 981 pipe in notably lighter than the 987 version. the purpose of this post is just to point out what to loosen (or what I did) to get the T tip swapped out. You basically have to slide the two sleeves over, push the muffler boxes apart and work the tip off. Not crazy hard, but was definitely using my feet to push things out of the way while I slid the tip off. Anyway, the main bolts you need to loosen are these 4 for the slide clamps (this is after I got the 981 tail pipe installed). 15mm hex. To allow the mufflers to move, you’ll want to remove these 4 bolts (2 per side). Note the two holes - those are where the bolts were removed. 13mm hex. And then finally, just to make sure things can wiggle as much as possible, these 3 bolts as well that bolt the exhaust support strut to the transmission. 13mm hex, iirc. After those bolts are removed, things can wiggle around enough to slide sleeves over to one side then push one muffler up while pulling the other down to make room to slide the tip off. to torque back up, the: 13mm hex bolts are 17 ft-lbs 15mm sleeve bolts are 22 ft-lbs

The latest "slide the crossover pipe over" hack. Search "8mm Bike seatpost clamps pair" on Amazon . Amazon.com : VAKTOK-Rugged Aluminum Alloy Bicycle Binder M8x65 Bike Seat Clamp/Bolt Seat Post Quick Suitable for folding bike mountain bike（Black）-2pcs : Sports & Outdoors Pics are self explanatory....

Long sporting drive through the mountains this weekend. Used exhaust in both positions and the bicycle seat stem clamps are easy and work perfectly. Nothing slips, everything locks and unlocks easily. Less than a minute to swap and the exhaust cools fairly quickly!

Big update. See this link for 2.9 muffler internal modifications. https://www.planet-9.com/threads/987-2-exhaust-interior-shots-followed-by-modifications.259472/?post_id=2261438&nested_view=1#post-2261438 I’m using sheet copper for my “beer can” baffle now too.

I’ve been following this thread and was wondering if this mod would work on my 987.1 Are the pipe dimensions, OD, ID and length compatible if I source a 981 exhaust tip ?

I am almost certain all the tips swap. Most after markets refer to 2005 -2012 boxster and cayman as one part.

The 981 tip is still a squared oval.....but the interior size change is HUGE. I can literally put a lsedge hammer all the way into into it all the way up to the crossover pipe. The 987.2 is necked down to about 2.25 inches. MUCH smaller.I have no idea if the crossover on the tip above helps or hurts. But the 981 has a deeper subtle tone change. and is dirt cheap.

When this was discussed about a year ago, I got myself one. Additional bonus - it is noticeably lighter. I can’t say I noticed the tone difference, but is relatively cavernous like you said, and is just a better part for the job (if you like a single tip)