Porsche 718 GT4 / Spyder / GTS 4.0L SOUL Valved Exhaust System


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. Engineered to pair well and not be overbearing with other aftermarket mods like over axle pipes and headers.

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 (at additional cost).
+  Weighs approximately the same as OEM PSE (37 lbs)
+  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.



Changing just the PSE muffler with stock over axle pipes offers a superb change in tone. It is smoother and higher pitched, more in line with the flat 6 character we’ve come to appreciate with previous generations of Boxster / Cayman. The PSE running valves closed had no real tone to it, we’d describe it as tinny, hollow, and rather boring as you can hear more of the intake than the exhaust. With our Valved Exhaust System the exhaust now has real character, and you can hear more of it everywhere with valves open and closed. Expect a smooth transition between valves closed and open modes. With the rest of the exhaust stock, the overall sound level at WOT with valves open may not sound dramatically increased. This is due to how aggressive the flow path is with valves open on the new 718’s PSE muffler. However, on our system the larger tubing diameter, distance traveled, and blending of the X-pipe gives the sound more depth and changes the tone to a smooth / higher pitch song. It sounds incredible especially from the outside, offering a true sporty note one would expect from the high end 4.0L. 

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 is 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. Tim Freeman

    Installed the GT4 valved exhaust. Are you kidding me. This thing rocks! Gurgles and pops. Sound is amazing.

  2. Driv200 (Rennlist)

    Oh My Gosh! This is the perfect exhaust combo with valved muffler. (Race headers no cats, OAP’s, and valved muffler).

    First day impressions:
    * It’s now a proper GT Car!
    * It’s higher pitch than expected and I freaking LOVE IT! Formula One V10 kind of sound!! Absolutely sounds like a true exotic.
    * up shifts are amazing. 3rd to 2nd-BOOM!
    * the long gearing is now a BONUS. 45mph speed limit in first gear sounds like 180mph Ferrari. It’s that good.
    * it screams when you want it. It’s docile ‘police friendly’ w/ gentle throttle input still in full open mode. And that’s without flipping switch to quiet or closed. it’s completely docile in the low rpm when you want to be quiet. This part amazed me even when it’s on full open.
    * throttle snaps are immediate & awesome. Parking lot blips are fantastic quick barks!
    * mustang / camaro guys are jealous at your favorite gas station when you start it.

    The range of the exhaust up to 8000rpm is insane. Better than I expected. Absolute dream perfection for the GT4.

    I’m having a hard time finding any drone. Sure, on decel with windows up around 2590-2900 you can hear it in cabin, but it’s more audible note than drone. This is the race headers and no cats’..of course you hear it. But it’s not tinny or droney at all. Windows up, AC on, I can carry a conversation at normal talk level. It’s a very balanced system. I’m trying to look for drone to post about it here. I really don’t have an issue thus far. My wife might even get to dinner w/o complaining or noticing it.

    Most vids I have seen were with race muffler or race header or OAP’s. This is full system with race headers(no cats), OAP’s, and Valved exhaust. The Valved exhaust is in full open (loud) mode b/c the chip for remote close is on back order. The exhaust in open loud mode allows me to be quiet with low throttle input. I’ll never use the closed ‘quiet’ function except for morning start up. At start up, the GT4 explodes to life! Freaking amazing every time. Once it warms up, it quiets down very nicely.

    I will add videos soon. Cold starts and revs, bridge tests, etc are coming. Cell phone audio does not do it justice. Doesn’t pick up the deep tones or high notes.

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