2023 Corvette Z06 LT6 engine

[dannobee]

New video on the 2023 Corvette LT6 engine. Flat plane crank DOHC 5.5L 460 lb ft torque, 670hp NA. Highlights (to me, at least) 6 stage dry sump with continuously variable oil pressure and the intake manifold with resonance frequency tuning between the two sides (like many of the NA Porsche's). Also, look at the intake tract, tapering down to the intake valves, as Darin Morgan has preached for a couple of decades now (7 degree taper on each side, 14 degree total angle). 12.5:1 compression ratio with the DI injectors accessible from the outside, near the exhaust ports. Also has 4-2-1 headers. Titanium connecting rods and intake valves, along with very short skirt (F1 style) pistons.

https://www.youtube.com/watch?v=_uta6RWwx7s

[1980RS]

It's going to be a screamer, can't wait to see one at the track or on the street.

[SupStk]

Still trying to figure the reason for the three stacked coils at TOP of the valve springs.

[MadBill]

It's going to be a screamer, can't wait to see one at the track or on the street.

The factory C8Rs have been racing (and winning championships) in IMSA's GTLM class* with this engine since January 2020. (*restricted to 500 HP)

[SupStk]

Hear lots of people stating viscous dampers have no place on performance engines and will cause the crank to break. Noticed there is one on the LT6. Interesting since flat plane V-8s have issues with balance and vibration.

[Ken_Parkman]

The difference with that damper is the factory engineers would have properly designed the damper, know the crank frequencies and driving orders. Probably the driving order criticality would change with the flat crank firing order, and probably the critical frequencies are higher. Pretty likely this one is properly designed.

Most (not all) aftermarket manufacturers do not even know what a damper is for.

[hoffman900]

It's a very cool engine. While nothing in it is technologically revolutionary, it's the same basic recipe for a high performance engine as many over the decades (DOHC, finger follower, 4 valve / cyl , pentroof chamber, etc.), the fact they were able to package all of it and do it so it makes economic sense for them is pretty astounding.

[SupStk]

The difference with that damper is the factory engineers would have properly designed the damper, know the crank frequencies and driving orders. Probably the driving order criticality would change with the flat crank firing order, and probably the critical frequencies are higher. Pretty likely this one is properly designed.

Most (not all) aftermarket manufacturers do not even know what a damper is for.

I have no doubt not only the damper but the whole engine was very well scienced out. My question is if viscous dampers are such a POS, why did it end up on this engine?

[Chris_Hamilton]

The difference with that damper is the factory engineers would have properly designed the damper, know the crank frequencies and driving orders. Probably the driving order criticality would change with the flat crank firing order, and probably the critical frequencies are higher. Pretty likely this one is properly designed.

Most (not all) aftermarket manufacturers do not even know what a damper is for.

I have no doubt not only the damper but the whole engine was very well scienced out. My point is if viscous dampers are such a POS, why did it end up on this engine?

I am confused too. I thought the reason viscous dampers were disliked was because of the viscous material used and that it "wore out" if memory serves the answer I got when I asked a question about fluidampers on here.

[Fusion Works]

Is anyone surprised that the Aftermarket may have kinda gotten it right and the haters were wrong? I understood the viscous damper to be great for engines that didn't have a dynamic rpm range, like industrial engines, tractors, big diesels, etc. Guess not. The concept seems sound if tuned for the engine you are in which used.

The New LT6 is brilliant. Proves that Corvette engineers are the best of the best even if GM is a slimy POS of a company. They have built a well thought out design and its going to be fascinating to see where this goes from here, especially since we are in the twilight of the IC engine.

The valve lash for life is an interesting concept. Theoretically if you matched your materials they shouldn't wear. Now add a DLC coating that is extremely slick and they may be right, that lash will last the life of the engine. I do wonder what the "life" is considered.

[hoffman900]

Is anyone surprised that the Aftermarket may have kinda gotten it right and the haters were wrong? I understood the viscous damper to be great for engines that didn't have a dynamic rpm range, like industrial engines, tractors, big diesels, etc. Guess not. The concept seems sound if tuned for the engine you are in which used.

The key word is tuned. Most aftermarket offerings (in anything) are just a guess. ATI and BHJ has the resources, but it'll cost you a lot to get it all measured and tuned, and it's only tuned for the system you test. Change even the flywheel weight and it's all screwed up.

I'd like to know what GM spent on making that damper work. When you account for salaries, technology, fringe benefits, and profit, it's probably not very cheap.

[PackardV8]

The New LT6 is brilliant. Proves that Corvette engineers are the best of the best even if GM is a slimy POS of a company.

Way OT, but can we name a multinational corporation which is not a slimy POS?

[Fusion Works]

The New LT6 is brilliant. Proves that Corvette engineers are the best of the best even if GM is a slimy POS of a company.

Way OT, but can we name a multinational corporation which is not a slimy POS?

Dunno, seems like it would be pretty easy to not be, but apparently its a race to see how low they can go.

[Fusion Works]

The key word is tuned. Most aftermarket offerings (in anything) are just a guess. ATI and BHJ has the resources, but it'll cost you a lot to get it all measured and tuned, and it's only tuned for the system you test. Change even the flywheel weight and it's all screwed up.

I'd like to know what GM spent on making that damper work. When you account for salaries, technology, fringe benefits, and profit, it's probably not very cheap.

Be interesting to see if they start showing up as failures in the next 5-7 years. Wonder if the engineers know there customer so well, that they realize the engines will never see more than 20-50K miles in its lifetime. LOL. Maybe these engine life is measure in the time it takes for a pair of New Balances to wear out.