GM: Engineers haven't tried stuffing Cadillac Blackwing V-8 in C8 Chevrolet Corvette

[brad66]

Source: https://www.motorauthority.com/news/...et-corvette-c8

Despite persistent rumors, General Motors President Mark Reuss said on the record that no one has tried stuffing Cadillac's new Blackwing V-8 in the mid-engine C8 Chevrolet Corvette.

Muscle Cars & Trucks reported on Reuss' comments Tuesday, in which he again underscored the 4.2-liter twin-turbo V-8 is a "Cadillac exclusive."

The brand has continued to defend the powerplant's exclusivity, despite the fact it's hand-built at the same performance center in Bowling Green, Kentucky, that handles Corvette engine production.



Cadillac 4.2-liter twin-turbocharged V-8

The website said to instead look for a revised version of the current Corvette Stingray's 6.2-liter V-8 to power the first batch of C8 Corvettes. The rumored engine designation is LT2 for the mid-engine application. The engine in the C7 Corvette is designated an LT1.

Although the Blackwing V-8 won't sit behind the driver in any mid-engine Corvette, do look for similar engines in the future. It's long been rumored the C8 Corvette will include DOHC V-8s for the first time. Underscoring the rumors is again the fact the Blackwing V-8, itself a DOHC layout, is assembled in the Bowling Green factory.

The necessary tooling and specialists are there to potentially assemble DOHC engines for the C8 Corvette. Specifically, rumors have pointed to a 5.5-liter DOHC flat-plane crank V-8 in both naturally aspirated and twin-turbo forms.



2020 Chevrolet Corvette prototype at Bowling Green Assembly plant

While the engine minus forced induction is rumored to make at least 600 horsepower, the two turbos will supposedly send the power figure to around 800 hp. We don't expect to learn anything about this purported powerplants at the July 18 reveal of the C8 Corvette, however.

Instead, the reveal will likely focus on the base model and its engine, which should see a modest power bump from the current LT1 V-8's 455 hp.

As for the Blackwing V-8, it's unclear where it will head next. All signs indicate it will power the future CT5-V "plus" model and perhaps a hotter redesigned Cadillac Escalade.

[electroVette]

There's no need for a hot-V V8 in the C8 since the engine is located forward of the rear suspension, providing space for side mounted turbos.

The hot-V design is primarily for packaging into longitudinal front engine layout. There is some potential benefit to the configuration since it enables a cross-bank exhaust manifold with very short exhaust runs to the turbos, but to my knowledge only BMW has brough such an exhaust manifold to market due to the cost:benefit ratio.

I expect future C8 variants will be powered by DOHC V8s built on the Blackwing architecture, but with the heads flipped around for conventional side-mounted turbos, as seen in the LT7 CAD drawing:

[JB]

Cool...ill pass on those upper echelon high output powerplants...

i prefer simple ohv engines that are durable light and relatively inexpensive especially if they deliver north of 500 hp and 500 lb/ft of torque...not to mention good gas mileage during daily driving.

personally i think this public statement is to get more attention to what the corvette team is preparing to launch in 8 days...than a statement of fact..

im sure there are examples of that blackwing running in test mules somewhere...lol


of course i know nothing about it and dont really care...

let those with deep pockets and a desire for dohc motors dream the dream...

been there and done that as a young man many decades ago.....then one day I test drove a c5 with its ohv ls1 and I was a convert.

[meyerweb]

I think everyone agrees there won't be an engine identical to the Blackwing in the V8. If nothing else, the ME location would likely require different motor mount locations, meaning a different cast for the block (even if the internals are the same). But as electrovette suggests, an engine with significant similarities and shared parts is almost a given. GM isn't going to spend what it costs to develop an all new motor to use in one vehicle only.

[John]

Thank you Brad for posting this article.

All they need would be to put a different valve cover on it (saying Corvette, maybe even ZORA), and eliminate the Hot-V set up, and voila, it is not a Blackwing, but it is an “X.” And everyone’s statements are true, yet the development costs are now spread out over a large sales unit base.

[SheepDog]

T.J said, 3 years ago, there was no mid engine Corvette in development . The C8 R tested with some variety of the Blackwing family of engine.

The C8 DHOC may turn out to be reliable and affordable in the Corvette tradition. Technology marches forward. The Caddy version will not bankrupt the buyers.

GM will test DOHCs against the Lt4 and LT5. Feasibility. Milage. Reliability. Make an informed, not emotional decision. The C4 ZR1 had some form of DOHC, Not really new.

There will be higher performance C8s. Corvette is busy testing, comparing and figuring it out. DOHC or push rod in the more high powered cars.


Question. Whether 800 HP can be effectively modulated within a 6000RPM power band?

The answer is probably no because the torque is condensed too much within 6K and is more effectively administered within a wider RPM range.

6K RPM is fine for 3/400 HP. But 800HP and 800Torque is easier done with wider RPM range. DOHV has wider RPM range than push rods. That is why they are doing it. Not to be stylish.

[Milliwatt Rob]

I remember when small block Chevy V8 meant a bored and stroked 1955 cast iron 265. With a Carter carburetor on top. I hardly consider an LT1/LT2 to be in the same league.

One thing I really like about the LT1 is its broad torque range and ability to propel the car at steady American speed limit velocities with the engine loafing along at under 2000 rpm. I hope that is not sacrificed with the DOHC set ups.

[TOMDOM69]

if these numbers are right then that means only 600ish hp for the Z06

[John]

I am not buying any number yet for the C8 Z06. However, even if that 600 HP number were to turn out to be true, the C8 Z06 would kick my C7 Z06’s times both in straight line and coming out of a corner apex acceleration.

[Klinn]

"Only" 600 hp. Wow, what times we live in.

I wouldn't be surprised if GM bumps the Z06 up to chase the Mustang GT500's 760 hp. Kind of like bragging "our mid-range model out-spec's your top of the line, and oh yeah, we've got the ZR-1 coming later which will be even faster".

[outofstep]

If GM decides to stick with NA OHV engines, they have basically given up on appealing to anyone but their current grandpa demographic.

Without a FI DOHC, the Vette isn't even on my radar. My money will likely be dropped on a lotus or porche.

[electroVette]

If GM decides to stick with NA OHV engines, they have basically given up on appealing to anyone but their current grandpa demographic.

Without a FI DOHC, the Vette isn't even on my radar. My money will likely be dropped on a lotus or porche.

Even if the Corvette engine performs better than those FI DOHC engines? What is it that you like about FI and DOHC from a user perspective?

[jsmatt]

I'll be patient, in the end it is the total overall performance of the vehicle that counts. The engine while important is just one of many factors in the entire equation. The upcoming reveal will give us some insight into where its all going. I'm particularly awaiting the total weight figures for the car.

[meyerweb]

Even if the Corvette engine performs better than those FI DOHC engines? What is it that you like about FI and DOHC from a user perspective?

While I don't agree with outofstep's point of view, I understand it and think lots of people will agree. Especially younger buyers who grew up on imported cars with high revving OHC engines. A DOHC engine (the FI part is meaningless: ALL engines are fuel injected today) has the image of modern, high-tech, state of the art. Especially if it's a twin-turbo DOHC. The same technology you find in Ferraris, Lamborghinis, McLarens, etc. An OHV engine is "old tech," like you had in 1960s muscle cars.

And when you're talking high performance sports / GT cars, image matters. Whether it makes logical sense or not. Showing up with your "antique" OHV engine when all your buddies have DOHC twin-turbo Euro sports cars would be embarrassing. [slight sarcasm intended]

[John]

I could care less what even my friends think about the motor in my car. If others do care, and choose to go elsewhere for their next sports car, good for them. However, so many advantages to our good ‘ole pushrod V8’s, including of less parts to go south, costs many thousands less, develops more low end grunt, outperforms so many of them on the track, is a smaller package, and more.

However, let us getting back to the 99% future probability, we will have a DOHC, 32V, twin turbo V8 option in our C8’s once the more powerful models come out.