Porsche 718 GT4 / Spyder / GTS Cayman Sport Package


Get a complete Soul Performance Products exhaust suite at once for package pricing!

Two exhaust upgrades combine for a superior sound! With two distinct tones, SOUL’s Valved Exhaust offers a significant sound improvement over factory PSE through a bespoke X-pipe muffler and anti-drone design features. Valves open mode elicits a smooth, sporty GT3-like tone for an invigorating driving experience. Valves closed mode calms down the volume for refined cruising with just enough presence to be appreciated. SOUL Competition Over Axle Pipes turn up the excitement further and improve the quality of the 4.0L exhaust sound.


Soul Performance Products Valved Exhaust System
Soul Performance Products Competition Over Axle Pipes

Fits all Porsche 718 GT4 / Spyder / GTS 4.0L vehicles (2020+) in North America. European vehicles use a different mounting style than North American vehicles. Contact us for a European conversion kit.
+  Weighs approximately 11 lbs / 4.9 kg less than OEM
+  All Soul Performance Products exhaust components are backed by the industry’s first and finest Lifetime Warranty for both street and track use
+  Designed and built in-house at our Willow Grove, PA facility

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  • Improve upon the factory design and achieve a throatier / smoother / higher pitched tone. 
  • Increase the presence and character of the exhaust note in the cabin while maintaining a reasonable level of resonance / drone while driving in both the valves closed and open modes through our signature drone fighting capabilities. 
  • Heighten aggressiveness with valves open while maintaining an overall sound level potential / quality that can still be reasonably driven on the street in combination with other complimentary aftermarket exhaust components – such as competition over axle pipes and header replacements.
  • Offer the ability to notably reduce the sound level of the car outside to fly under the radar when necessary.
  • Achieve an effective delta in sound between both modes for two usable, well engineered experiences – mild and wild. 




With valves open, our Valved Exhaust System follows a similar design to our Race Exhaust System through an X-Pipe that merges the exhaust flow for a higher pitched, smooth sound. With valves closed, the exhaust is routed through smaller piping and a bespoke SOUL muffler we designed to fit with the X-Pipe in the confined space above the rear diffuser and meet our sound goals. This muffler was crafted to match our high standard of drone fighting mufflers like the rest of our existing Boxster / Cayman line that we have become known for. 

Internally this muffler is quite unique. It has little to no restriction in the flow path, using straight through piping that is perforated to allow exhaust gasses to escape and become muffled in the surrounding packing material of the muffler body. We incorporated a second internal X-pipe to allow the exhaust flow to merge smoothly. These characteristics combined were crucial towards reducing and smoothing out the drone in the 1,800-3,000rpm range while enhancing that higher pitched note we were after in both the valves closed and open conditions.

In addition to the bespoke muffler design, there are several other unique characteristics we’ve brought into play on this system which revolve around the secondary flow path entering the muffler. The key thing to note here is that the valves open flow path is not limited to the 2.5″ external X-pipe flow path only, some of the exhaust flow is still going through the secondary flow path even though the valves are open. This design is essentially utilizing the entire secondary flow path and muffler design to smooth out the tone and drone while running valves open. Please note the carefully tuned length of the piping entering the muffler, as the sound waves and exhaust pulses have a longer distance traveled through the piping for a notable effect on sound attenuation. Utilizing this secondary flow path for honing in on the optimal cruising cabin presence, we were able to go aggressive on the design of primary flow path with larger diameter 2.5″ piping without incorporating resonators or mufflers.



We found that the particulate filters in the over axle pipes put a big damper on the overall sound level and how it carries into the cabin. Think of it like a cork in the middle of the exhaust, letting a PSE muffler replacement tease you but not giving you the full experience. Combining our Valved Exhaust System with our Competition Over Axle Pipes is when the skies open up, the sun shines down and the Porsche Gods have blessed us with the sound we’ve all been waiting for. Inside and outside the car, windows up and down, the experience is nothing short of transformational. At wide open throttle it sounds like a weapons grade symphony. Very reminiscent of a GT3 at 9k, and arguably better than any stock GT3 you’ll ever hear on the street. Ditching the factory over axle pipes finally allows the car to have some burble on deceleration but nothing too over the top, just enough and just right. When you do a hard shift, a visceral crack erupts to really put a smile on your face. Not like a shotgun blast going off, more like a reward for actually driving the car how it’s meant to be driven. The sound is aggressive, but not overly so like you just took an RSR off the track for street shenanigans. When you’re off throttle cruising around, it’s relatively docile and comfortable (that secondary flow path at work). If you want to fly under the radar and significantly cut down on sound level outside the car, you simply close the valves and away you go in stealth mode. However, even with valves closed the tone and character of the exhaust is still there, not dead muted like the PSE muffler. It has cabin presence, some ever so mild drone/resonance in low rpms that we consider quite reasonable compared to the other configurations we’ve tested – even with valves open it’s quite reasonable. We’d almost say it’s more a character of the system and it’d be a shame if there wasn’t any to tease you into squeezing on the gas to hear more of it. We highly recommend installing a SOUL Valve Controller Kit to override the PSE programming at your convenience, and hear what it has to offer under 4-5k rpm in the first few gears – it’s worth it!

CONSTRUCTION:  Each system is assembled in house in the USA out of mandrel bent, thick wall .065″” T304L stainless steel. Back purged TIG welding (with ARCAL™ Prime argon gas) ensures proper weld penetration and longevity. Water jet cut flanges are made to ISO 9001:2015 standards with tolerances of +/- 0.003 inches for extreme precision. We fabricate each exhaust using thick gauge aluminum fixtures which act as a great heat sink during the welding process and prevent warping not only of our products, but the fixtures themselves to ensure perfect fitment.

BOLT ON AND GO:  Every component is rigorously quality-checked, tested in a fixture to guarantee fitment, and then foam packed to ensure they arrive in perfect condition. New high grade hardware and OEM Porsche gaskets are included for installation.

LIFETIME WARRANTY:  Enjoy your SOUL exhaust components with confidence on both the street and track as they are covered by our Lifetime Warranty! Our team will quickly work with you to resolve any issues or answer any questions that you may have.


  1. chalkspyder (Rennlist)

    The last time I posted was right after I had a chance to drive the car before the complete system was installed. The system at that point was missing the over axle pipes so only the valve controller and the valued exhaust was installed. I honestly could have taken the car home and would have been happy with the improvement over factory PSE. Well, I’ve had the completed system (value controller, valued exhaust and over axle pipes – the street package) for almost two weeks now. Soul has created some great videos inside and outside of the car with variations of valves open and valves closed so I’ll spare you the details about what he has already documented and skip to the experience of driving the car under various conditions:
    -Highway driving
    Cabin sound at highway speeds (70 MPH+) is surprisingly good…it is definitely louder than the factory noise level but still allows you to have conversations comfortably. Now if you step on it, you are reminded that the system is there. I noticed a similar behavior at normal neighborhood speeds…its loud when you want it to be and manageable off throttle…it’s the same on the highway.
    -Droning: I had a hard time finding any droning to report. I have done about 50 miles of highway driving (staying between 2200 and 3500 RPM at 60-70 MPH) specifically centered on understanding if there is any droning its not there. What was interesting was that I could induce a faint amount of droning right at about 2800 RPM but only with the factory PSE enabled (i.e. the valve controller turned off). Bottom line, droning is not really present and I don’t plan on turning off the valve controller so the net of this is positive.
    I have not dyno’d the car with the new system, but there for sure is a horsepower gain. You can physically feel the engine breathing better…the throttle response was good before but it is even better now.
    -Pops and crackles
    There is a nice benefit of the over axle pipes….the return of a bit more pops and crackles on upshift and downshift. It even has a new pop on startup. This is all a welcomed surprise after driving the car before the over axles were installed.
    Overall, very happy with the system. Looking forward to more backroads and tunnel runs

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