Porsche 981 GT4 / Boxster Spyder Long Tube Street Headers


Soul Performance Products Long Tube Street Headers are built around large diameter, free flowing HJS HD 200-cell catalytic converters with long tube runners for maximum gains in power, throttle response, and flat-six engine tone out of the 3.8L engine. Add performance without throwing a check engine light!

+  Fits all 981 Porsche GT4 / Boxster Spyder vehicles (2015-2016)
+  Added performance without a check engine light
+  Direct bolt on installation – instructions included
+  All Soul Performance Products are backed by a renowned Lifetime Warranty for both street and track use

Porsche 981 Boxster / Cayman OEM Header Gasket Set

Optional genuine OEM replacement gaskets to replace your old or worn gaskets.

SKU: POR.GT4.STH Categories: , ,


DEVELOPMENT AND TESTING:  By creating a unique application for the 981 platform, we’ve focused on sizing the runners (2”) and collectors correctly to extract maximum power from the 3.8L engine. We chose appropriately sized HJS HD 200 cell catalysts to flow enough power for sustained high RPM use – where the GT4 is at home. Don’t settle for smaller, cheaper catalysts when power and durability is concerned. Third party dyno testing on a Dyno Dynamics dynamometer revealed gains of 30 whp when paired with a tune, with 12 whp gains unlocked by Street Headers alone after the tune had been applied.

CONSTRUCTION:  Each header is assembled out of T304L stainless steel and rigorously quality checked in-house. Proven design elements including port matched flanges, smooth radius primary tubing, and collectors that optimize the exhaust flow all work in conjunction to maximize power gains.

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. We use a large and appropriately sized catalyst to allow for maximum gains – no compromises here!

BOLT ON AND GO:  Each product is tested in a fixture to ensure perfect fitment. 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 headers themselves are backed by our Lifetime Warranty.

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



  1. Michael James

    I have had these headers on my GT4 for the last 6 months and couldn’t be happier. The change in exhaust note is a bonus to the extra power and torque the car now makes.

    Leave the factory exhaust valves shut and the neighbours won’t hate your choice of car, but open them up in a tunnel, and feel the hairs on the back of your neck stand on end from the fantastic sound coming from just behind your head. The sound emanating from the car at full throttle is incredible and the crackles and pops on overrun are intoxicating!!

    Having the extra 33hp at the top 1000revs is good to have on a race track, but the extra torque from 3500rpm up to 6000rpm makes the car much more enjoyable on the road, reducing the need to wring the car’s neck constantly.

    The service and advice from the team at Soul Performance Products was a major part of the decision to stick their headers on to my much-loved GT4, a decision I am happy with every time I go for a drive in the car.

  2. Andy Demar

    I spent the whole month contemplating which Sport (catted) headers I should get since I don’t intend to race my car, my first and top choice was Dundon Motorsports Headers since they are local to me and have the best proven performance gain, but you have to pay for top quality products and unfortunately, I didn’t have the budget for their custom Sport headers. The other headers I considered were Cargraphics and Fabspeed. But I ended up with Soul Performance Products not just because they were the least expensive but all the people who had them had very positive things to say so I went with them. I was communicating back and forth with Mike and he was always at disposal to answer any questions I had. They shipped it right away and it took me about a week to receive the headers (PA to WA). The installation guide they provided were simple and I was able to install without much difficulty. The sound didn’t change much (which is a good thing I like the stock sound), maybe a tad bit louder, raspier and drier sound. After the installation of the headers the car felt definitely quicker eliminating much of the lag that bothered me in the first place. I would say with the BMC Air Filter & SoulPP Sport Headers, 3/4 of the lag was gone and I could feel the car pulling harder throughout the rev range. At this point, if you are not as picky as me I think you will be happy with just the Filters and Headers.

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