Best Cat-Back Exhausts for the 2015–2021 WRX and WRX STI: 5 Top Picks Compared

The best cat-back for a 2015–2021 WRX or WRX STI depends on the exit you want: the Revel Medallion Touring-S ($940.50) for a hand-welded quad system, MAPerformance ($999.99–$1,079.99) for twin mufflers and resonators, the Invidia R400 ($1,535) for the classic quad-tip look, the HKS Hi-Power SPEC-L II ($1,800) for a system HKS lists at under 23 pounds, and our own RES × JDMuscle valvetronic system ($2,370) when you want loud and quiet in one exhaust. Every pick below was verified active on our store today, for the VA WRX and WRX STI sedan.

The VA is a sedan-only generation in the US, which simplifies life: one body style, one routing. What differs is sound, weight and tip finish — and every system here fits both the FA20 WRX and the EJ257 WRX STI unless its listing says otherwise.

1. Revel [15-21 WRX/STI] Medallion Touring-S Catback — $940.50

The Revel Medallion Touring-S ($940.50) is the craftsmanship-per-dollar pick. Per its listing, it is built from full SUS304 stainless steel with 1.5mm-wall mandrel-bent piping, fully hand TIG welded with laser-cut flanges, and a straight-through muffler design using heat-resistant Advantex packing rated to 1200°F. Quad exit, touring manners, and the lowest price on this page — that combination is why it leads the list.

2. MAPerformance [15-21 WRX/STI] Catback Exhaust — $999.99–$1,079.99

The MAPerformance Catback ($999.99–$1,079.99 depending on configuration) is the configurable one. Per its listing, the Rev2 system replaces the factory exhaust with mandrel-bent 304 stainless tubing, twin polished mufflers and twin resonators, for more power and torque and a deeper note — with one explicit fitment note from the same listing: it does not fit cars with the SPT exhaust. If your VA still wears the SPT system, pick another row in the table.

3. Invidia [15-21 WRX/STI] Gemini R400 Cat-Back, Stainless Quad Tips — $1,535

The Invidia Gemini R400 ($1,535) is the classic quad-tip answer. Per its listing, it is a full 76mm (3-inch) mandrel-bent 304 stainless system pairing the R400 Gemini muffler configuration with single-layer polished stainless tips for the clean, classic look, in one listing covering both the WRX and the WRX STI. Titanium-tip and full-titanium R400 versions sit above it in the same family ($1,634 and $1,726) if the tips are where you want to spend.

4. HKS [15-21 WRX/STI] Hi-Power SPEC-L II Catback — $1,800

The HKS Hi-Power SPEC-L II ($1,800) is the lightweight JDM pick. Per its listing, it is a SUS304 stainless system weighing just under 23 lbs — 54% lighter than stock, per HKS — with burnt titanium-wrapped 94mm tips, a 65mm midpipe feeding a 50mm Y-pipe, and the cannonball muffler design the Hi-Power name is known for. If the scale matters but you still want two mufflers and four tips' worth of presence, this is the one.

5. RES × JDMuscle [15-21 WRX/STI] Valvetronic Catback — $2,370

Our own flagship is the RES × JDMuscle Valvetronic Catback ($2,370). Per its listing, it is a T304 stainless system with a remote-controlled valvetronic muffler — valves open for the full sound, closed for the neighborhood — covering both the WRX and WRX STI sedan in manual and CVT form. It is a Special Order item, so plan the lead time into the build. Two exhausts in one is exactly what valvetronic means, and it is why this system sits at the top of the range.

Quick comparison

How to choose — and what to do next

Decide the volume first, then the weight, then the finish. Resonators and muffler count decide how the car sounds at 70 mph; titanium and thin-wall stainless decide what it weighs; valves decide whether you have to choose a volume at all. Then keep the build coherent: pair the exhaust with the cooling in our VA WRX top-mount intercooler guide and the suspension in our VA coilover guide, both published today.