Kooks CT5-V Blackwing Long-Tube Headers Review 2022-25

The Kooks long-tube headers for the 2022-2025 Cadillac CT5-V Blackwing are the single biggest bolt-on you can add to GM's 668-horsepower super-sedan. The Blackwing's supercharged 6.2L LT4 V8 makes 668 hp and 659 lb-ft from the factory, but its restrictive cast manifolds and OEM converters choke exhaust flow the moment the blower builds boost. Swap them for Kooks T304 stainless long-tubes with high-flow GREEN catted pipes and, with a supporting tune, the LT4 wakes up with 80-100 rear-wheel horsepower and 90-120 lb-ft of torque. Below is our full review, real dyno context, primary-tube sizing, and how the headers pair with a cat-back exhaust.

Why the CT5-V Blackwing Is the Ultimate Header Candidate

The 2022-2025 Cadillac CT5-V Blackwing is a 668-hp supercharged super-sedan and the last manual-transmission V8 Cadillac will ever build. Its 6.2L LT4 shares its Eaton R1740 TVS supercharger architecture with the C7 Corvette Z06, producing 659 lb-ft of torque and a 0-60 mph time of 3.4 seconds with a top speed over 200 mph. That much boost makes exhaust backpressure the enemy: forced-induction engines are far more sensitive to a clogged exhaust than a naturally aspirated motor, because every PSI of backpressure fights the supercharger trying to cram air in.

The factory exhaust manifolds are compact cast units sized for packaging and noise, not flow. Long-tube headers replace them with equal-length primary tubes that scavenge each cylinder more effectively, dropping exhaust gas temperatures and unlocking the airflow the LT4 already wants to move. On a supercharged engine, that is why headers are the rare bolt-on that returns Corvette-level gains rather than the single-digit numbers you would see on a naturally aspirated sedan.

Kooks 2″ x 3″ Long-Tube Headers Review

The Kooks 2-inch x 3-inch long-tube header and GREEN catted X-pipe kit is our top pick for the CT5-V Blackwing. It is handcrafted from T304 aircraft-quality stainless steel with 3/8-inch laser-cut flanges, full TIG welds, equal-length primaries, and merged collectors that step up into 3-inch high-flow GREEN catted pipes. Those pipes carry 400-cell metallic-substrate catalytic converters that keep the car 49-state emissions legal while supporting well over 1,200 horsepower — far more than any Blackwing build will ever need.

How Much Horsepower Do the Kooks Headers Add?

Kooks 2-inch long-tube headers with GREEN catted pipes deliver dyno-tested gains of 80-100 rear-wheel horsepower and 90-120 lb-ft of torque on the CT5-V Blackwing when paired with a supporting tune. That is a supercharged-specific result: the LT4 runs 10+ PSI of boost, so relieving exhaust backpressure lets the Eaton blower move more air for the same rotor speed. Header-only (no calibration) gains are smaller — typically in the 20-40 whp range — because the factory ECU has to be recalibrated for the new airflow before the LT4 can take full advantage.

In practical terms, a Blackwing that leaves the factory around 590-600 rear-wheel horsepower can push toward 680-700 rwhp with headers and a tune — genuinely Corvette Z06 territory. Gains scale further if you later add a pulley or blower upgrade, since the free-flowing headers are already sized for over 1,200 hp. This is the rare bolt-on where the exhaust system becomes a foundation for the rest of the build rather than a restriction you have to work around later.

2″ vs 1-7/8″ Kooks Headers: Which Primary Size?

Kooks offers the CT5-V Blackwing header in two primary-tube sizes. The 2-inch x 3-inch kit is built for maximum top-end power and future power-adders, delivering 80-100 rwhp. The 1-7/8-inch kit ($3,647.24) trades a little peak power for slightly stronger low-end exhaust velocity, delivering 70-90 rwhp and 80-110 lb-ft. For a mostly-stock Blackwing that keeps the OEM supercharger, either works beautifully; for a car that will see pulley or blower upgrades down the road, the 2-inch primaries are the smarter long-term choice.

Pairing Headers With a CT5-V Blackwing Cat-Back Exhaust

Long-tube headers replace everything up to the OEM mid-pipe; a cat-back exhaust handles everything behind it. On the supercharged LT4, cat-backs are primarily a sound-and-weight upgrade — expect a louder, deeper V8 note and drone control rather than meaningful power — but they are the perfect complement to the headers. Our three most popular Blackwing cat-backs are the CORSA Xtreme with 4.5-inch carbon-fiber tips, the AWE SwitchPath with valve-controlled volume, and the Stainless Works polished-tip system.

Each has a distinct personality. The AWE SwitchPath ($2,995.00) is the daily-driver's choice: a vacuum-actuated valve lets you toggle from a quiet, drone-free commute to a full-volume track roar at the push of a button, so you get the best of both worlds. The CORSA Xtreme ($3,208.66) is the loudest and most aggressive of the three, using CORSA's patented RSC sound-cancellation to stay drone-free at cruise while delivering a race-car snarl under throttle. The Stainless Works system ($2,565.61) is our value pick — a hand-built 304 stainless cat-back that shaves weight over the factory setup and adds a classic American V8 rumble without the premium price. All three bolt directly behind the Kooks GREEN catted pipes.

CT5-V Blackwing Header & Exhaust Comparison

Here is how the header kits and cat-back exhausts stack up for the 2022-2025 CT5-V Blackwing. Power-gain figures are with a supporting tune; cat-back exhausts add sound and reduce weight rather than meaningful horsepower on the supercharged LT4.

Installation, Emissions & Tuning Notes

The Kooks headers bolt to the factory mid-pipe, so no custom fabrication is required, but a long-tube swap on the LT4 is still a labor-intensive job that typically means dropping components for access — we recommend professional installation. Because the kit uses 400-cell metallic-substrate GREEN catalytic converters, it keeps the car 49-state emissions compliant, unlike catless or "off-road" headers that are race-use only. Budget for a supporting ECU calibration afterward; without a tune the ECU will not fuel and time the engine for the new airflow, and you will leave most of the 80-100 rwhp on the table.

A common CT5-V Blackwing package is Kooks long-tube headers, a matching cat-back exhaust, a cold-air intake, and a dyno or handheld tune. At NLP Performance in Tampa, FL we help Blackwing owners spec the exact combination for their goals — whether that is a clean 49-state street car or a foundation for a future blower upgrade. Every part on this page is in stock and ships from our catalog of thousands of performance components.