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Article By JOSH JACQUOT and DAVE VANDERWERP, JUL 19, 2019; quoted from Car and Driver:

The newest version of the 6.2-liter small-block V-8 makes up to 495 horsepower and 470 lb-ft of torque and doesn't require routine engine-out service.

Chevy’s small-block V-8 has been a part of the Corvette legacy since 1955. It continues in the C8 as the LT2, making more power and more torque (495 horsepower and 470 pound feet with the performance exhaust) than the LT1 in the outgoing car. The LT2 expands the small-block’s capabilities with more-efficient intake and exhaust manifolds, a more-robust lubrication system, and a new camshaft. It uses the same bore and stroke, as well as the same forged crankshaft, rods, and 11.5:1-compression-ratio pistons, as the LT1 upon which it’s based.

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All Stingrays will now get a dry-sump system to accommodate the chassis’s increased track capability, which includes sustained lateral acceleration beyond 1.00 g. Previously, dry-sump lubrication was only available as part of the C7 Stingray’s Z51 package. The system goes from one pump to three multistage scavenge pumps—one in the valley of the V and two in the crankcase. The oil reservoir is now mounted to the engine rather than being bolted into the engine bay separately as it was on the C7. A larger liquid-to-liquid oil cooler is capable of 25 percent more thermal rejection.

As small-block chief engineer Jordan Lee explains, a side benefit for having this unconventional engine-mounted sump is an ease of assembly. Oil can now be added during the engine-build process rather than when the car is going down the assembly line. Thanks to the better scavenging, the engine is mounted an inch lower in the Corvette than before, with a much shallower oil pan. Lee says this also accounts for the reduction in total oil volume, which drops from 9.7 quarts in the LT1 in the C7 to 7.5 quarts of 0W40 in the C8's LT2.

Lee also confirmed that the C8 doesn't require any routine engine-out services—often an expensive bugaboo with mid-engined cars—and that the spark plugs and other ignition components, along with the accessory belts that are tucked up next to the passenger compartment at the front of the engine, can be accessed with the engine in place. However, swapping out, say, the oil pump will require dropping the engine.

The camshaft’s intake lobes remain the same as the LT1’s, but lift on the exhaust lobes is slightly increased. The LT2’s cam phasing, which alters intake and exhaust timing together, is about the same as before. The rest of the valvetrain is carryover from LT1 as is the LT2’s rev limiter, which remains at 6600 rpm.

The additional output, which jumps from 455/460 hp and 460/465 lb-ft in the LT1 to 490/495 hp and 465/470 lb-ft in the LT2 (the higher figures are with the optional performance exhaust, which adds a second set of flapper valves) is due to the better breathing achieved with the engine in its new position behind the passenger cabin along with the other small tweaks mentioned above. Chief-engineer Lee also points out that small reductions in windage were achieved by the more precise oil scavenging. Before, oil up in the head would drip back down into the pan, slightly impeding the spinning crankshaft, but now that passage has been closed, and the oil is scavenged out of the V.

With the engine behind the driver, engineers were less concerned with forward sightlines and free to make the LT2 taller than the LT1. A new intake manifold with equal-length runners is mounted so that the engine now breathes from the back of the car, further shortening the distance between the throttle body and intake valves, which improves flow.

New stainless-steel exhaust manifolds also use equal-length runners, which collect using a race-car-like four-into-one design. The LT1’s cast manifolds had an intermediate step, going from four into two into one in the C7. An active exhaust changes the LT2’s sound in different drive modes, but isn’t a factor in peak output.
 

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Two of the three "cons" are bogus, IMHO.

There are many dealers selling at MSRP, so "dealer markup" is only a "con" if you're not a smart shopper.

And the exhaust pipe "con" is just silly. The most iconic Corvettes of all, the 1963 - 67 Stingrays, had the pipes on the outer ends of the rear fascia. So did the C1, C3 and C4.
 

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Think we will see the Caddy 4.2L DOHC Blackwing V8 in the C8? This Hot-V, twin turbo has a lot of potential. Compact, lots of power 550HP & 627 ft/lb in the Cadillac V. Maybe a flat plane crankshaft in the C8? And its already being made at Bowling Green.
 

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Think we will see the Caddy 4.2L DOHC Blackwing V8 in the C8? This Hot-V, twin turbo has a lot of potential. Compact, lots of power 550HP & 627 ft/lb in the Cadillac V. Maybe a flat plane crankshaft in the C8? And its already being made at Bowling Green.
There was a lot of speculation re the Blackwing being used in the C8 before much was known about the C8. Since it has been revealed, little if anything has been said.
 
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