Wednesday, 13 November 2019

2020 Corvette Stingray: Inside The New Vette’s Beastly Engine & Transmission

  • The 2020 Chevrolet Corvette Stingray is the quickest Corvette to date.
  • With the Z51 Performance Package, zero to 60 times are quite impressive.
  • Included below are cutaway photos of the transmission and a gear ratio chart.

Chevrolet continues to put out more performance details on the upcoming and hotly-anticipated mid-engine Corvette. Like every other number associated with this car, it keeps looking good. Very good. As in Chevrolet confirms the 2020 Stingray is the quickest in Corvette history.

How Fast Is The 2020 Corvette Stingray?

If you opt for the Z51 Performance Package, you can hit 60 mph in 2.9 seconds and do the quarter mile in 11.2 seconds at 121 mph. Out of the box. Even if you decide not to go with the Z51 Package, the base Stingray will do zero to 60 mph in three seconds flat, and run the quarter mile mark in 11.2 seconds at 123 mph. Again, out of the box.

Right off the rack. Out. Of. The. Box.

I know guys who spent lots of time and money to get numbers close to that, and the fact you can simply buy a car that quick that isn’t a high-priced exotic should, by now, be taken as a blessing upon all us gearheads.

How The 2020 Chevy Corvette Stingray Does It

Chevy is rather forthright when talking about how all this gets done. Yes, they say, the overall package – rear weight bias, tire technology, aerodynamics, chassis tuning – is there, but they also (gleefully) concede “The LT2 Small Block V8 and eight-speed dual-clutch transmission are in many ways the stars of the show.”

The powerplant in question is a naturally-aspirated 6.2-liter V8, putting out an SAE-certified 495 horsepower and 470 lb-ft. of torque when equipped with the performance exhaust. With a standard dry sump system, Chevy says this is now the most track-capable Stingray in history. I won’t argue with that. Besides, you’ll need a full-on dry sump setup since the new Vette can pull acceleration levels exceeding 1g in all directions.

“The LT2 is one of our best efforts yet in Corvette’s history of naturally-aspirated, high-performance Small Block V8 engines,” said Jordan Lee, GM’s Global Chief Engineer of Small Block Engines. “This engine is incredibly powerful and responsive.”

2020 Corvette Stingray engine.
The LT2’s pan-mounted oil filter and cooler assembly has cored oil and coolant passages, allowing for a 25 percent increase in cooling capacity over the LT1. Photo: Chevrolet.

Every Breath You Take

In addition to oil and lubrication, Chevy really opened up the breathing with this new plant. The intake system is a “low restriction design” with 210 millimeter intake runners and an 87 millimeter throttle body. Exhaling is taken care of with a performance exhaust manifold featuring a four-into-one design with twisted runners for thermal expansion.

Chevy reworked the cams, now with a big 14 millimeters worth of gross lift on the intake and exhaust; with a duration increase for both profiles on the bump stick. Finally, the LT2 retains a variable valve timing system, with 62 crank degrees of cam phasing authority.

“Power is readily available when the driver needs it,” Lee added.

The 6.2-liter LT2 Small Block V8 in the 2020 Chevy Corvette Stingray.
The 6.2-liter LT2 Small Block V8 in the 2020 Chevy Corvette Stingray. Photo: Chevrolet.

Transmission Tech

All this is rather tried and true and about what you’d expect from a modern engine, even if there is but a single camshaft living down in the vee. Where Chevy really breaks new ground for the company is in the gearbox. This is Chevy’s first eight-speed dual-clutch transmission (DCT) and it does two things: put the LT2’s power to the pavement and a smile on every driver’s face. The Tremec transmission provides uninterrupted torque delivery regardless of the situation, road or track, according to the engineering team.

“The goal from the beginning was to design a transmission worthy of an exotic supercar that is fun to drive everyday,” said Terri Schulke, GM Global Chief Engineer of Transmissions. “We achieved that goal by combining the best attributes of the LT2 and the DCT, and I think the impressive performance numbers speak for themselves.”

2020 Chevy Corvette Stingray transmission cutaway.
2020 Chevy Corvette Stingray transmission cutaway. Photo: Chevrolet.

How Does The 2020 Corvette Stringray’s Transmission Work?

The Stingray’s DCT uses two concentric wet clutches that are opened by springs, then closed by hydraulic pressure. The two clutches work in unison for more efficient torque delivery as drivers toggle between gears. A separate lube circuit is used to cool the clutch and reduce parasitic losses. From there, holes in the outer housing allow for the wet clutches to operate moist instead of submerged.

Going with a dual-clutch, paddle shifter transmission supports the Stingray’s new mid-engine architecture, but it also gets you a very low center of gravity. Further, it allows for better weight distribution and maximum traction under acceleration. The unit houses the sensors, final drive, controls system, lubrication and cooling hardware, and the differential. Sweet!

Final Drive Ratios Chart

2020 Chevy Corvette Stingray
Eight-Speed Dual-Clutch Transmission Ratios
Gear Ratio
1st 2.91
2nd 1.76
3rd 1.22
4th 0.88
5th 0.65
6th 0.51
7th 0.40
8th 0.33
Reverse 2.63

Two Different Differentials

And speaking of differentials, check this out: there are two you can choose from. First, there’s the mechanical slip differential that’s standard on all 2020 Stingrays. The “mLSD” as they call it, has an effective final drive ratio of 4.9:1 for lots of punch in a straight line.

The electronic limited slip differential or “eLSDs” is offered on the Z51 Performance Package with an effective final drive ratio of 5.2:1. Obviously, this diff works much better during track driving. Interestingly, the mLSD and eLSD share a common ring and pinion gear ratio of 3.55:1.

All of this, combined with some truly trick software, shows just how far the Corvette has come since its introduction with a Blue Flame six and two-speed Powerglide, no?

2020 Chevy Corvette Stingray
2020 Chevy Corvette Stingray. Photo: Chevrolet.

2020 Chevy Corvette Stingray Availability

The 2020 Corvette Stingray coupe and convertible are available to order at certified dealerships. Production begins at Bowling Green Assembly later this year. In addition, the new Stingray will embark on a cross-country tour leading up to its on-sale date. Corvette specialists, along with the vehicle and numerous other displays, will stop at over 125 dealerships nationwide, as well as major consumer events.

Tony Borroz has spent his entire life racing antique and sports cars. He is the author of Bricks & Bones: The Endearing Legacy and Nitty-Gritty Phenomenon of The Indy 500, available in paperback or Kindle format. Follow his work on Twitter: @TonyBorroz

2020 Chevy Corvette Stingray: Engine & Transmission Gallery

Photos & Source: Chevrolet.



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