01
304L Stainless
1.5–1.8mm wall. TIG-welded. X-ray inspected. Will outlive the chassis.
- Mandrel-bent on a CNC fixture
- Back-purged welds throughout
- Heat-shielded muffler section
Founder-built · Bethlehem, PA
Electronic valvetronic catbacks
In stock · ships in 2–3 days
LoudQuietLoud is a setting.
One catback, two personalities — 304 stainless, TIG-welded, with electronic exhaust valves you command from the driver’s seat. Bolt-on. No tune. No CEL. 67 builds across 19 marques, from $1,679.
19
Marques
67
Builds
7d
Production
∞
Structural warranty
THE LINEUP BY MAKE
SHOP BY BRAND
Nineteen makes, every chassis we build. Pick your badge — it takes you straight to the kit.
01 / THE CORE LINEUP
Street
48 builds02 / TUNER ROYALTY
JDM
8 builds03 / THE FRONT ROW
Exotics
11 buildsSec. 02 — Engineering
Built right.
Sold direct.
The full system, drawn to the kit we ship.
Flip the valves — watch it work.
Closed: 5–7 dB over stock. Cabin-civil cruise. Passes any noise meter. Civilians won't notice.
“It's a switch you flip from the keyring. That's the whole pitch.” — the founder
02
Electronic Valves
CNC-billet housing. Wireless remote, keychain fob, cabin controller.
- No phone app, no subscription
- 2-year electronics warranty
- Spare actuator stocked stateside
03
Bolt-On, No Tune
Direct to OEM mid-pipe flange. No cutting, no welding, no CEL.
- 1.5–3 hours on a lift
- Gaskets + V-band clamps included
- Doesn't touch cats or sensors
04
Forever-Backed
Lifetime structural on the pipes. A real human answers your warranty email.
- 2 years on electronics
- Direct founder contact
- Built to order in 7 days
REAL BUILD
FOUNDER'S BUILD
REAL B58, REAL SETUP
This is my daily. G30 540i running the QHCE valvetronic catback behind a real supporting setup — not a press car, not a rental, not an actor. Same driver, same build, every demo.
- CarBMW G30 540i
- EngineB58 3.0T
- TuneMHD Stage 2 — Burble Tune
- DownpipeVRSF Downpipe
- ExhaustQHCE Valvetronic Catback
CREATOR BUILDS
Genuine reactions.
Real owners, their own cars, their own footage. Not our camera, not our edit — and not a stock photo in sight.
SOUND ON
OWEN'S M4 CS
2020 M4 CS · F82 · S55
COMFORT · VALVES CLOSEDCOMFORT · VALVES OPENSPORT PLUS · VALVES CLOSEDSPORT PLUS · VALVES OPEN
I bought this M4 CS off the guy who builds QHCE exhausts. Then I put one on it. Four states in one take — Comfort and Sport Plus, valves shut and valves open. Sound on.
Sec. 04 — Beta testers
From the
garage.
Real cars, real installs —
the first three builds out the door
Sounds like an M-car factory option. Cabin is dead quiet with the valves closed. WOT with them open and my neighbors hate me. Bolt-on was 90 minutes on a lift.
I was about to drop $2,800 on another brand's catback. Glad I waited. This kit is better-welded, sounds better, and was half the price. Carbon tips look factory.
The remote is the move. I leave it on the keyring. Apartment garage in the morning — valves closed, no neighbor problems. Highway with friends — valves open. Zero compromises.
The
Founding 50.
The first 50 builds get founder pricing — locked in, never repeated.
$150Off your build
CarbonFree tip upgrade
FreeGround shipping
Drop status
In stock5 builds
FormatSmall batches
QueueOrder received
Founder pricingLocked for 50
Founder pricing comes through a QHCE creator’s code · In-stock builds ship in 2–3 days
Sec. 05 — FAQ
Short answers to
long questions.
If yours isn't here,
the full FAQ has 10+ more
If your car is on our supported chassis list, yes — bolt-on to the OEM mid-pipe flange. No cutting, no welding. Each product page lists exact year + engine compatibility.
No. Catback only — doesn't touch cats, downpipes, or any sensor the ECU monitors. No CEL, no tune required.
Valves closed: 5–7 dB over stock (cabin-civil, noise-meter friendly). Valves open: full personality — deep snarl on cold starts, war-cry on WOT.
Five builds are in stock and ship in 2–3 business days: 540i/530i (G30), M340i/M440i (G20/G22), 340i/440i (F30/F32), C-Class (W205) and Q50/Q60 (VR30). Every other build is made to order — about 7 business days to build plus 4–5 days in transit. Northeast (PA/NY/NJ/CT) typically delivers 1–2 business days after we ship.
Lifetime structural warranty on the pipes. 2 years on electronics. 90 days on cosmetic finish (tips + laser engraving). Full terms on the warranty page.
- For off-road / track use only
- Not legal for highway use in all 50 states
- Buyer assumes responsibility for local compliance
- For off-road / track use only
- Not legal for highway use in all 50 states
- Buyer assumes responsibility for local compliance
- For off-road / track use only
- Not legal for highway use in all 50 states
- Buyer assumes responsibility for local compliance
- For off-road / track use only
- Not legal for highway use in all 50 states
- Buyer assumes responsibility for local compliance
