STILLEN Black Friday Sale | 10% Off at XPH
13th Nov 2026
The STILLEN Black Friday Sale is live at Extreme Power House (XPH). Save 10% on STILLEN and shop cat-back exhausts, cold air intakes, and suspension upgrades for the Nissan Z, 350Z, 370Z, Infiniti Q50, and Infiniti Q60.
Start with what you want to notice from the driver’s seat. A cat-back changes the exhaust note when you accelerate. An intake brings out more sound from under the hood. A sway bar kit changes how the car feels as it turns in and settles into a corner.
2023–2026 Nissan Z | Street Series and Competition Series Exhausts
For the 2023–2026 Nissan Z with the VR30 twin-turbo V6, XPH lists two STILLEN cat-back options. The Street Series is aimed at drivers who want a more pronounced exhaust note for everyday use. It uses 304 stainless steel, 2.5-inch mandrel-bent tubing, an X-pipe, and polished stainless steel mufflers. The Competition Series is the louder option if you want the exhaust to be a bigger part of the driving experience. When comparing the two, listen to what each system sounds like under light throttle and at a steady cruise as well as under acceleration. A cold-start clip gives you a sense of the initial volume, while an in-cabin clip can tell you more about what you’ll hear on the highway. Check the product listing for your exact trim and preferred tip configuration.
2023-and-Newer Nissan Z | Adjustable Sway Bar Kit
The STILLEN Adjustable Front and Rear Sway Bar Kit, part 304345, gives Nissan Z owners a way to address body roll. XPH lists the kit for the 2023-and-newer Z. The bars are stiffer than stock and retain the factory outer diameter so the original bushings can be reused.
Sway bars resist the difference in suspension movement between the left and right sides of the car as it corners. An adjustable front and rear kit lets you change roll stiffness at each end. If your Z already has different springs, coilovers, or tires, take those changes into account when choosing the settings.
Nissan 350Z and 370Z | Two Ways to Change the VQ Sound
For the 2003–2009 Nissan 350Z (Z33), XPH lists the STILLEN stainless steel dual cat-back, part 504350D, for VQ35DE and VQ35HR coupe and roadster applications. The system bolts to the factory catalytic converters and uses polished dual-wall tips. It’s an option if you want a more noticeable exhaust note and a bright, traditional finish at the rear bumper.
For the 2009–2020 Nissan 370Z (Z34), XPH lists the STILLEN Gen 3 Dual Hi-Flow Ultra Long Tube Intake, part 402852. The kit uses two polished aluminum intake tubes and washable oiled filters positioned ahead of the radiator. The filter location matters when you plan the installation and later filter service, so review the instructions before setting aside time for the job. If sound is your priority, listen for how the induction note changes as you open the throttle.
Infiniti Q50 and Q60 | Match the Upgrade to the Engine and Body Style
The 2016–2024 Infiniti Q50 3.0T has a STILLEN stainless steel cat-back option with polished tips, part 504451, or burnt-style tips, part 504452. XPH lists the polished-tip system for rear-wheel-drive and all-wheel-drive 3.0T sedans. Polished tips give you a finish closer to the factory look, while burnt-style tips add more color at the rear bumper.
For the 2017–2022 Infiniti Q60 3.0T, XPH lists separate coupe-specific cat-back systems with polished tips under part 504453 and burnt-style tips under part 504455. The Q50 and Q60 share the VR30 engine in these applications, so check the body style as well as the engine when you pull up the listing.
If you drive a 2014–2015 Infiniti Q50 with the 3.7L V6, XPH lists the STILLEN Gen 2 Cold Air Intake, part 403230, for the non-hybrid V37. It uses twin polished aluminum intake tubes and urethane heat shields. The 3.7L and 3.0T Q50s have different intake layouts, so start with the engine designation when shopping.
Shop the STILLEN Black Friday Sale at XPH
Whether you’re comparing exhaust tones for your Nissan Z, planning an intake for your 370Z, or picking a tip finish for your Infiniti, start with your model year, engine, and body style. Browse the STILLEN lineup at Extreme Power House and save 10% during the Black Friday sale.