Porsche 718 Boxster / Cayman SOUL Sport Catalytic Converter Downpipe


Replace the restrictive factory catalytic converter with a bolt on, high flow HJS HD 200 cell catalytic converter downpipe for more power, response, and turbo sound without a check engine light or noxious fumes.

+  Fits all North American Porsche 718 Cayman / Boxster vehicles (2017+)
+  Peak power gains of 14 whp and 24 ft-lbs of torque
+  Added performance and tone without a check engine light – no ECU tune needed
+  Weighs 4.7 lbs / 2.1 kg less than factory exhaust components (22.38 lbs vs 17.65 lb)
+  Direct bolt on installation – hardware and instructions included
+  All Soul Performance Products components are backed by a renowned Lifetime Warranty for both street and track use

SKU: POR.718.SCC Categories: , ,


DEVELOPMENT AND TESTING:  The 718 is rather quiet in factory format. Replacing the restrictive factory catalytic converter with a freer flowing unit adds to drivability and also unlocks the sweet sounds of the turbo without adding any negative notes to the overall exhaust tone. The HJS HD 200 cell catalytic converter and smooth mandrel bent piping ranging from 90mm down to dual 55mm oulets encourages better throttle response and a more exhilarating exhaust note. Easy to bolt in with no modifications required, this is a great, reversible solution to make your Boxster or Cayman more exciting.

POWER:  Verified independent dyno testing at Growler Motor Labs revealed real, repeatable peak gains of 14 whp and 24 ft-lbs of torque with a noticeable improvement in the mid RPM range.

CONSTRUCTION:  Each downpipe is assembled out of mandrel bent, thick wall T304L stainless steel, then rigorously quality checked. Back purged TIG welding ensures proper weld penetration and longevity.

HJS CATALYSTS:  The highest quality catalytic converters available, known for their industry leading flow and durability. They are efficient enough to meet strict EURO 4 emission standards while still allowing for an increase in flow – all without a check engine light. The HD design uses premium triple foil winding for maximum strength. The brazing stripe is an extra feature in the interest of durability – it prevents the core from moving or experiencing any damage from sustained high horsepower abuse.  The 200 cell design uses a premium wash coat of precious metals to achieve a high level of effectiveness at catalyzing even with the increase in exhaust flow.

BOLT ON AND GO:  Each downpipe is rigorously quality-checked, tested in a fixture to guarantee fitment, and then foam packed to ensure it arrives in perfect condition.. New hardware is included for the two bolt flanges. Thorough installation instructions are included in the box for a straightforward install that can be performed by most DIY enthusiasts.

LIFETIME WARRANTY:  Enjoy your SOUL exhaust components with confidence on both the street and track as they are covered for life! Our team will quickly work with you to resolve any issues or answer any questions that you may have. We cover our HJS catalytic converters with an unprecedented 3 year warranty while the materials and workmanship are backed by our Lifetime Warranty.

This product is not CARB certified and may not be legal for use on emissions controlled vehicles; intended for off road use only


  1. Charles McDowell IV

    The sound while driving the car is greatly increased. It sounds like the PSE, but noticeably louder and without any drone. Which is exactly what I was hoping for.

    The turbo is barely noticeable – just enough to hear it without it being too much.

    Most importantly, my butt dyno is telling me that the downpipe added some power. The car feels to pull through the gears much easier. Enough so for me to actually notice a difference.

    Overall, I think this was worth the money and made the car more fun to drive – without costing an arm and a leg.

  2. Matt Chow

    Lovely turbo spool sounds coupled with great (louder & deeper) low end grunt and a bit more power according to the unofficial butt dyno. I’ll hopefully be attempting some more video from the outside soon. Fit and finish of the downpipes is great, the o2 sensor installed with no problems.

    Removal of the stock setup required some wrestling of clamps and stubborn screws, but everything was installed and buttoned up within 2.5 hours which included getting the rear up on jack stands and removal of the rear wheels.

    I’m definitely looking forward to driving more with the downpipe as well as hopefully getting to Cobb so they can play around with the new found flow and power.

  3. Lukejt (Rennlist)

    I’ve had the Soul catted down pipe installed for a couple weeks, and driven the car quite a bit. It’s pretty awesome. Sounds really nice in sport mode. Definitely a slight bump in seat of the pants performance all around. I will get some video soon and share it for everyone to hear. When you’re not on it, the sound level in the cabin is really nice and low. But when you’re on the gas, it seems to be more on par with the artificial sound level produced by the Porsche SoundAktor or whatever that noise generator is called, except it’s not artificial and annoying (mine is disconnected) The car also sounds really sweet when upshifting with the PDK and sport Chrono. More crackles with he Soul downpipe, and even sometimes when not in sport mode. Also super stealthy when you want to be.

  4. rmartin031 (Rennlist)

    I recently installed a Soul Performance downpipe on my 718 Cayman S a few months ago. I wanted to get a few miles on it before giving my impressions and now unfortunately have to put it to bed for the northeast winter. I also want to start by saying I have owned 2007 Cayman S, 997.1 Carrera S , and I also currently own a 997.2 Carrera GTS with a sharkwerks muffler bypass. I should also state my car came with PSE so not sure how that effects others outcomes.

    Sound: Definitely a change in noise, the note and engine just sounds more heightened and engaging, more definition in the different sounds. It sounds less muted, “uncorked” if you will. I think this helps reveal the characteristics of this engine more and help stand on its own in the world of Porsche boxer 6s. I originally was having issues with the sound but the downpipe greatly helped me develop that relationship with what was a great performing car. The personality has been discovered in this great engine for sure. Although the volume may have gone up slightly thats not what this was about but the new sounds will peak the senses.

    Performance: Not that I was searching for more performance, but yeah noticeable change here as well. Since this is my first turbo experience really modifying I wasn’t really expecting much in the way of performance, same level of any exhaust on a N/A motor. This is not the case here, sport cat downpipes really do make a bigger difference on the turbo. The car is much more responsive and seems ready to go all the time, spools are on point. Not there was that much lag in the 2.5 but it just feels sharper and quicker revving. Seems like the biggest power increase comes from the 3k-6k rpm and then gains at the top end but not as pronounced. But boy we definetly picked up some noticeable thrust/shove in that middle chunk.

    Anyway I hope this helps anyone on the fence

  5. Jesse Garrett

    Quality, Fit, Finish and response time are the major key performance indicators when looking to purchase after-market products for your high-end sports car/exotic car. Soul Performance Products

    I can’t speak enough on the quality, fit and finish of the products I’ve purchased over the last year. I have a build underway on another vehicle that they will be supplying parts for, they just don’t know it, yet.

    Also, the response time with inquiries is extremely fast. Shipping is same day in some cases, it has been for me. Competitors don’t come near this type of customer service.

  6. InTgr8r (718Forum)

    Received mine a short while ago as well,
    The attention to detail by Soul is incredible, right down to the packaging.
    I have received MANY shipments over the years and none where packed like the Soul package I received.
    The system was completely encased in foam.

    As to the product itself, the quality is fantastic!

  7. Tom Z

    The car has become a symphony of beautiful events. The hi flow downpipe enhancing the appreciation of various engine noises not heard prior to its installation as well as of course the little bump in power which is quite noticeable. The shifter with it’s perfect notching sounds and enhanced connectivity to the car itself all make for a perfect selection of upgrades not breaking the bank completely reversible and productive or truly harmonious driving experience not present in stock form. Thanks again. A pleasure meeting you today and spending time with you and getting a tour of your fabulous facility. The same appreciation comes from my wife really enjoyed herself as well. Thanks again. Tom Z

  8. Ian Savaya

    Great fitment, doesn’t come with gaskets so be sure to save yours.
    Yes, it is worth it.
    Yes, it makes a difference. (better mid-range pull and better throttle response)
    It comes with new hardware which is handy. I was able to do it without removing the exhaust or removing the wheel. You just need the right length extensions.
    Overall great product.

  9. ced357 (Rennlist)

    I’ve done a number of suspension upgrades, Soul performance Sport cat down pipe and exhaust, half cage, recaro seats, Giro disc brakes and running track wheels 245’s up front and 305’s in the rear RE71r’s. Love the performance of the car and love chasing down GT3’s on track:-)

  10. lamacan (Rennlist)

    just got the car back. drove about 11 miles home from Greg’s shop.

    the cats are superb. exactly what i was looking for.

    my first thought when i got the T was: anyone who said these cars don’t have turbo lag is lying.

    yes, its maybe the best of any turbo car from a perspective of perceptible lag, but its still noticeably a turbo car. not anymore. the throttle response improvement is astonishing and the first thing i noticed the second i hit the gas out of the shop. the cats are worth it for that improvement alone.

    i was coming from a 981 GTS which is probably the most aggressive stock PSE ever. i wanted more of that NA sound. that was my goal with this mod. i’d describe the sound as a mix between a 981 GTS and a 991.2 GT2RS. you get more of that hum a la GT2RS, letting you know there’s actually an engine back there, but the theater of the 981 GTS is more present now, albeit a few decibels quieter. the cracks and pops are more prevalent on decel/downshift, but they also sound far more natural. more cracks, less burbles.

    ZERO drone. if you hold 6th gear (i am PDK) at highway speeds that “hum” is more prevalent, but not at all droning (vibration in the cabin). none whatsoever. 7th gear removes it entirely.

    the ONLY negative i would say, which is purely subjective, and i was very aware of in advance, is i hate turbo noise. turbo noise is now more prevalent. soul acknowledged this to me when i spoke with John over the phone. they also mention it on their website. it’s really only noticeable more at idle. kind of like a wheezy noise. it doesn’t make me regret the mod at all, just something to note that if i could “tune” it out, i would.

    9.5/10. absolutely recommended.

  11. Todd B (Rennlist)

    Finally had some time this past weekend to install the Soul downpipe. Installed it on my 18 Cayman GTS, took about 3 hours. It’s a straight forward swap. Everything fit/lined up. Car was up on my storage lift, so I put the lift on the lowest lock position. The height was prefect to use a creeper to roll under the car and work on it.

    The exhaust sounds a bit different. There’s a good low bark on a cold start. But the real change is the throttle response when driving the car. The response is now more like my GT3, the engine is always there, with just a slight movement of the throttle. Before I could always tell it was a turbo because it would have a slight lag every now and then, but now, I did not any lag in any situation. The torque comes on strong and the car really pulls. I can only image that this thing would be like with a tune. Well worth the upgrade.

  12. rvacs (718 Forum)

    LOVE LOVE LOVE my SOUL Downpipe that I had installed. Car when put in SPORT mode has a beautiful GROWL…makes its a whole new experience!! HAPPY SOUL customer!

  13. Lou718cs (718Forum)

    I had my shop install the Soul Catted Down Pipe yesterday and my drive home was very nice. I am sure the OEM is fine but the Soul does add a bit more to the car. Although I did not install because of sound, I noticed the car has a bit more growl to it and the overall sound was satisfactory for me (my soundaktor fuse is removed). In addition, they provide a bit more performance and a bit less weight. Soul catted down pipe should last a long time and I am sure I will be happy with my decision to have it installed. I have PSE and did not replace OEM. Also, no engine lights or issues once they installed the system.

  14. apexarmorsolutions.com

    Really amazing upgrade for the 2.5L Turbo Flat 4 Cayman GTS. It adds a bit more exhaust sound/ note, but not a huge amount (You’d want an exhaust for that).
    It also cleans out the exhaust note a bit and makes it more refined.

    However there is an immediately noticeable boost in performance and a near elimination of any low end turbo lag under 3,000 RPM.
    I have an APR Stage 1 tune, and sport mode now has more responsiveness than even sport plus mode.

    Adding the downpipe in conjunction with a tune greatly enhances the driving experience of the car and makes it feel like a completely different car.

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