The 2025 Corvette ZR1 isn’t short on impressive specs – from the four-figure horsepower, to the 1,200 pounds of downforce, to exhaust gas that exits the rear pipes so fast it provides thrust, the new “King of the Hill” is an “utter monster.” Given all that, it should come as no surprise that the Corvette ZR1 will most likely be subject to the gas guzzler tax, as fuel economy is not exactly a focus for this particular vehicle. What’s more, the C8 ZR1’s twin-turbo engine does not incorporate Active Fuel Management (AFM) technology, otherwise known as Cylinder Deactivation.
During an interview with (now retired) Corvette executive chief engineer Tadge Juechter at the recent Corvette ZR1 debut event in Miami, GM Authority asked about AFM and the ZR1’s twin-turbocharged 5.5L V8 LT7 engine.
“We don’t want to put that hardware in,” Juechter told GM Authority Alex Luft during the interview. “It’s all lightweight components, and even though the LT7 redlines to 8,000 RPM, it’s still pretty fast for a turbo motor.”
For those readers who may be unaware, GM’s AFM system, otherwise known as Cylinder Deactivation, shuts down half of the engine’s cylinders during light driving (or low-load) conditions, thus improving fuel economy without reducing performance when the skinny pedal hits the carpet. The technology has been used in a variety of GM applications, including high-performance engines like the naturally aspirated 6.2L V8 LT1 and supercharged 6.2L V8 LT4, both of which rev to 6,600 rpm.
Despite the benefits of AFM technology, the technology simply isn’t the right fit for the ZR1’s LT7, which, as Juechter points out, revs up to 8,000 rpm and focuses on low weight and relative simplicity in order to maximize performance. Also notable is the naturally aspirated 5.5L V8 LT6 cradled by the C8 Corvette Z06, which revs up to 8,600 rpm, and, like the LT7, does not include AFM technology. As GM Authority has covered previously, the LT7 is essentially a twin-turbocharged variant of the LT6 engine architecture.
Engine output for the Corvette ZR1 is rated at 1,064 horsepower and 828 pound-feet of torque. Under the skin, all C8 Corvette variants ride on the GM Y2 platform, while production takes place at the GM Bowling Green plant in Kentucky.
Comments
BS response. Real response is that it wasn’t In the LT6, so they weren’t adding it to the LT7. It’s not in the LT6 because it has less torque than the 5.3 at cruising speed, (dont believe me, look aththe torque curve. LT6 is making 300TQ vs 330 for the LM7) and would never have the torque to run in 4 cylinder mode. No thought was given to “oh hey, we think that there’s no room for this”.
So much of this car was dictated by Porsche and BMWs monopoly over GT boards it’s not even funny. “Must be 2WD” “no more than 5.5L displacement” if you suck that bad, maybe it’s time to drop the 911 instead of changing the rules on Corvette, and it sucks paying 100+k for a car just to have all GT races deny you entry.
C8 should of been a 6.2L AWD 1200HP behemoth with the engine in the front, but rules are rules. Not it’s got a euro-turdbine in it. 😡
Steve…. what??
The real answer:
Wealthy buyers don’t want AFM.
And MPG seems to be a non-factor with the Billionaires too…
Shocking!
Can we get rid of the AFM in the trucks as well without having a warranty voided out? They did whenever the chip shortage was going on. You could get a 6.2 Silverado with no AFM. Some people get better gas mileage without it, and a whole lot better reliability of the truck as well.
No one gets better mpg without it, they are either A, lying or B, it is a placebo effect. It has been shown in testing and third party to save somewhere between 5-8% give or take in savings, you can’t argue physics.
The specs on the 2025 Corvette zr1 is incredible and is sure to be a formidable competitor to anything on the road. But ultimately, I’m interested in how it’ll fare against the Dodge Demon 170 which goes 0-60 mph in 1.66 seconds and covers the quarter mile in 8.91 seconds with a 151 mph trap speed. Can the Corvette match any of those 3 figures?
we would have to see it on a prepped surface, which the demon can only do so on.