My friend Roddy Mitchell lives in the neighborhood, fixes cars for a living, and just bought a Cadillac CT5-V Blackwing. I rode shotgun. So this is a passenger’s review, which is the only kind I’m qualified to write about a car that isn’t mine.
The short version: it’s a four-door Cadillac with a supercharged V8, and it makes the curve on Grigsby Chapel Road a little more fun. That’s as specific as I’m going to get on a public website.
What he bought
The CT5-V Blackwing sits at the top of Cadillac’s V-Series sedans. Cadillac rates its hand-built, supercharged 6.2-liter V8 at 668 horsepower and 659 lb-ft of torque, sends all of it to the rear wheels, and quotes 0 to 60 mph in 3.4 seconds. It lists from $98,900 before options, as of October 2026.
A six-speed manual is standard. Roddy’s is a 2025 with the optional 10-speed automatic, and it was incredible. Purists will tell you the Blackwing is a manual car. Purists weren’t in the passenger seat.
The butt dyno report
Cadillac says 668 horsepower. I can’t verify that. My butt dyno has never been calibrated, and for this trip it was installed on the passenger side. What it can confirm is “plenty.”
Here’s the funny part. Roddy owns a real dyno. His shop does dyno tuning for a living. Of the two of us, he’s the one who could tell you the actual number, and he’s the one choosing not to change it. More on that below.
How it handles
This is a sedan that weighs more than two tons. duPont Registry’s test car came in at 4,123 pounds. Cadillac throws a lot of hardware at making it not feel that way.
Every Blackwing comes with Magnetic Ride Control, dampers that adjust themselves to the road as you drive, and an electronic limited-slip differential. Brembo brakes are standard at all four corners.
All of it is adjustable. On top of Tour, Sport, Track and Snow/Ice modes, there’s a V-Mode button on the steering wheel that calls up your own setup: steering, suspension, engine and shift behavior, brake feel, engine sound, and five levels of Performance Traction Management, from Wet to Off. You may need an engineering degree just to understand the menus. Of course, Roddy knows what every one of them does. That’s why he drives and I ride.
Grigsby Chapel is the warm-up. I can’t wait till we get to take it to the Dragon, the Tail of the Dragon on US 129 at Deals Gap, where the Tennessee side is said to pack 318 curves into 11 miles. The speed limit there is 30 mph, which, on that road, is plenty.
The ceramic brakes
Roddy’s car has the performance package, which Cadillac calls the Precision Package, and that’s how it got carbon ceramic brakes: cross-drilled carbon ceramic rotors at all four corners. Cadillac’s pitch is heat resistance, so the tenth hard stop feels like the first, and a big cut in unsprung weight, the weight the springs don’t carry, which helps both ride and handling.
The package doesn’t stop at brakes. It also brings redesigned front knuckles for more camber, stiffer bushings, revised springs and damper travel, retuned Magnetic Ride and differential software, and Michelin Pilot Sport Cup 2 R tires. duPont Registry put the price at $18,000. That’s a lot of money for brakes. It’s a fair amount for brakes, suspension and tires that came from the factory with a warranty, which turns out to be the theme of this post.
The tune he isn’t doing
Roddy runs RM Motor Werks in Knoxville, and performance is the job. His shop’s site lists engine management and custom tuning as his specialties. The Blackwing can be tuned, too: HP Tuners added support for 2025 and 2026 Blackwings in February 2026, Roddy’s year included, once the engine computer goes through an upgrade service.
I can tell he really wants to. He hasn’t, because he doesn’t want to give up the warranty. Cadillac covers the powertrain for six years or 70,000 miles, and on a supercharged V8 that is a very nice thing to keep in a drawer.
I’m not a lawyer, so here’s what the FTC says. Under the Magnuson-Moss Warranty Act, a manufacturer can’t void your warranty or deny coverage just because you used aftermarket parts. It has to show the aftermarket part caused the problem. That’s the law. In practice, when a tuned engine breaks, the tune is the first suspect, and you’re the one doing the explaining.
So the man with the dyno is driving a stock car. Watching a tuner leave a car alone is like watching me use a website somebody else built. You can see what it costs him.
About Roddy
Roddy has worked on my cars for a decade. He was the only person besides me who ever turned a wrench on my BMW, which means he got to fix all of my screwups. It was not a short list.
He’s an incredible mechanic. According to his shop’s site, he has more than 20 years in the automotive and motorsports business and started RM Motor Werks more than ten years ago in a two-bay building. The shop on Enterprise Drive now does oil changes and brakes, performance upgrades, fabrication, CNC machining and dyno tuning, on cars from Hondas and Fords to Porsches, Ferraris and McLarens.
If you’re in Knoxville and you have a car you care about, RM Motor Werks is where I’d take it. It’s where I have taken mine for ten years.
For now, the Blackwing stays stock. Somebody on this street has to be the responsible one, and it was never going to be me.
Quick answers
How much horsepower does the Cadillac CT5-V Blackwing have?
Cadillac rates the 2026 CT5-V Blackwing’s hand-built, supercharged 6.2-liter V8 at 668 horsepower and 659 lb-ft of torque on premium fuel. A six-speed manual is standard and a 10-speed automatic is optional. Cadillac quotes 0 to 60 mph in 3.4 seconds.
Does tuning a CT5-V Blackwing void the warranty?
Not automatically. The FTC says a manufacturer can’t void a warranty or deny coverage just because aftermarket parts were used; it has to show the aftermarket part caused the need for repair. In practice, when a tuned engine or transmission fails, the tune is the first thing anyone looks at, and that is the risk an owner weighs against Cadillac’s six-year, 70,000-mile powertrain warranty.
The photos are Cadillac’s images of the CT5-V Blackwing, not Roddy’s car. Real ones are coming.
Sources: Cadillac, CT5-V Blackwing and specifications (checked October 12, 2026); Cadillac, warranty FAQ; Federal Trade Commission, “FTC Offers Tips on Making the Most of Your Auto Warranty” (January 14, 2011); HP Tuners, Blackwing support announcement (February 24, 2026); duPont Registry, 2026 CT5-V Blackwing Precision Package review (September 26, 2026); GM Authority, “2026 Cadillac CT5 Drive Modes Explained” (February 28, 2026); Wikipedia, Deals Gap; RM Motor Werks, Meet the Team.
