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4.5L V8 Turbo Corvette & 2016 Flagship Cadillac Sedan

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#1 · (Edited by Moderator)
We Learn GM Plans 4.5-liter V8 Turbo for Corvette, Flagship Cadillac Sedan Coming in 2016
Carscoops
September 18, 2013


We recently came across some interesting information from a credible source about future products for GM's Chevrolet and Cadillac brands, and which to some extent, are interconnected.

We'll begin with Chevrolet as we learned that the Corvette's immediate future includes a more potent version of the 4.5-liter twin-turbocharged and direct-injection engine that GM debuted on the Cadillac Elmiraj Concept just last month.

We're told that the new V8 will most likely be used in the successor of the Z06, rumored to be called Z07. While in the Elmiraj, it produced an estimated 500hp, in the Corvette, it could push out as much as 600 horses (unconfirmed).

Full article at link.
 
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#124 ·
As for Cadillac, the million dollar question is CAFE. GM can continue to do high performance V8s for Cadillac based on the LT1. But to do a special V8, it would have to have a long lifespan to be worthwhile. Northstar lasted nearly 20 years. GM can do continual updates to the LS/LT engine because it goes into a gazillion trucks and SUVs. Therefore it takes less time to make up the cost. GM can go on updating the OHV engines right through the decade every couple of years if it wants to. But a "special" V8 for Cadillac would need volume and or longevity. With NA V6s about to breach the 340hp mark and turbo V6s about to pass 400hp, the need for a regular V8 for the Cadillac line is pretty much gone. Therefore the only place for a special V8 would be on the high end performance cars. Top engines are shared with Corvette because it has the volume to make it worthwhile. If Cadillac gets it's own, say, DOHC V8, the first question to be asked is will it last in the lineup for at least 10 years (say, 2024 or 2025) or will it be obsolete. There's no question like that on the volume V8s due to truck use.
I could see a 4.5L pushrod being made and being aimed at small caddies / Camaros and maybe even trucks as an entry V8 engine but still struggling to hit High volumes outside of
the Camaro and maybe V sport ATS/CTS BUT the TTV6 is there for that and why go SMALLER then the truck 5.3L is we are talking a "base" V8 and the 5.3L is volume and probably a tune away from being a sports car engine in itself
 
#125 ·
Building the 5.3 liter v8 isn't less expensive to build or lighter or smaller in size than the 6.2 liter v8 so I'm confused as to why you would think this would be a better choice then the 6.2 for the Camaro?

Real world fuel economy would be within one mpg and if it were really the issue...a change in rear gearing would be a less complicated way to achieve higher mpg s...


Thanks in advance...
 
#128 ·
In that video the designer addresses both the engine, and that there is a third concept in the series coming, perhaps two years down that is about "Arrival", a formal sedan......I wonder if THAT is the Glamour concept?
 
#129 ·
I thought the Elmiraj was the Glamour concept. I mean seriously why does Cadillac even need concepts when these vehicles are ready almost for production? The concept that debuted at Pebble Beach looked to be almost 90 percent ready to go into production with the exception to the interior which was over the top and unrealistic in a car costing less than $300k. Mark my words... If Cadillac put out that car or even the Ciel in the next year, people would be lined up with money to buy it. The S class, 7 series, the Porsche Pan, and even the respective Bentleys would lose sales.

I don't care about concepts anymore. I want cars that I can buy. Concepts were for a time before the Internet when magazines showed pictures of cars of the future, 10 years in the future.
 
#132 ·
Cadillac could use the Dohc twin turbo v8 for all those euro chic buyers that dig reading about specifications on a page...

For those that prefer corvettes to drive....continue with the 6.2 liter in both naturally aspirated and supercharged form for higher performance and for those of use who actually buy and own them less expensive to own and maintain...

Corvette buyers don't want 4.5 liter twin turbo engines.

We want ohv and 6.2 liters! Supercharged or naturally aspirated...

Let the other brands of sports cars offer smaller displacement turbos....

We prefer to be unique in this day and age...

I don't believe in its near price range much can keep up with the total package of corvette....

Mr Ackerson likes Dohc and twin turbos for Cadillac....he thinks that's what buyers in that market segment want...

I disagree as I personally prefer the performance, lightweight and fuel efficiency of an ohv v8 in my corvette to the Dohc v6 in my AWD CTS....(its a nice engine but since it costs as much to build as my corvettes LS3....if I had a choice I would have always prefer the LS3 in the caddy...

JMO
 
#139 ·
The present LT1 was making just under 500 hp with a different tune. It was taken down to 460 with NPP ...

My suggestion would for the Camaro if need be....just tune the LT1 down a little further if gm wanted the Camaro to have a few ponies less than the Camaro.

I never believed it was necessary but the LS3 in the present Camaro SS makes 426 hp versus the corvette LS3 rated at either 430 or 436 ( with NPP).

Its been working for years for both corvette and Camaro. I don't really see the need for the same weight and sized 5.3 liter engine in the Camaro...

Just keep a 6 pony spread in hp for marketing and reap the rewards.

The reason the c7 has the 6.2 liter is it got better gas mileage in AFM mode as a 3.1 liter than the smaller and often rumored 5.5 liter v8 that never materialized.

I'm not trying to be difficult I just tend to think the 6.2 belongs in the Camaro SS and the higher performance corvette deserves a supercharged version. Its a formula that works quite well.

I do believe Cadillac will get a twin turbo v8 as its customer base would or could during conquest sales like it.

I'd rather have a supercharged or twin turbo 6.2 ohv liter in Cadillacs but that's just a personal choice. I don't like to pay more for what I consider inferior heavier and more complex technology...ie Dohc 4.5 liter twin turbo v8 s..

Hell maybe Cadillac will just amp up the 3.6 twin turbo with greater displacement and or more boost?

Why bother going from a v6 to a v8 when displacement can increase a little and just turn up the boost?

Direct injection allows for more controlled and efficient combustion so boot has the ability to go higher for more power...

Two extra cylinders for what reason? Marketing?

Maybe....
 
#142 ·
4 hp? Between ls3 powered Camaro SS M6 vs corvette LS3...

I wouldn't sweat the difference.

I expect the same for the Sixth gen Camaro gen 5 v8 and the c7.

I fully expect the higher performance c7 will be a supercharged LT4 6.2 liter.
 
#144 · (Edited)
I don't see a 4.5L V8. For many reasons, I think GM will turbo the 5.3L. It's easier to hit target hp, it has more torque, the longer stroke gives better fuel efficiency, and it's already in production. They can also do a higher compression, lower boost, for even better fuel efficiency. We'll see if they can integrate AFM with the turbos.

In the SAE paper, GM looked at a 4.7L V8 when developing the gen V, but it had worse fuel economy than the 5.3 - it ran in V4 mode for shorter time - and had less power. A 5.7 was considered, and although performance improved, again, the 5.3 was the fuel economy champ.

GM centred the gen V development around the 4.3 V6 - so l don't see bores smaller than 96mm or larger than 103.25 mm. imho if any gen V will be turbocharged, the 4.3 will be.
 
#148 ·
I don't see a 4.5L V8. For many reasons, I think GM will turbo the 5.3L. It's easier to hit target hp, it has more torque, the longer stroke gives better fuel efficiency, and it's already in production. They can also do a higher compression, lower boost, for even better fuel efficiency. We'll see if they can integrate AFM with the turbos.

In the SAE paper, GM looked at a 4.7L V8 when developing the gen V, but it had worse fuel economy than the 5.3 - it ran in V4 mode for shorter time - and had less power. A 5.7 was considered, and although performance improved, again, the 5.3 was the fuel economy champ.

GM centred the gen V development around the 4.3 V6 - so l don't see bores smaller than 96mm or larger than 103.25 mm. imho if any gen V will be turbocharged, the 4.3 will be.

They did - and they didn't.

They did not in a globally comprehensive clean sheet - everything is wide open sense.

They did but only after the four big, hugely important fixed assumptions were in place - which of course completely spiked any chance of a fully optimized smaller than a 5.3 V8.


And then all that + the Vette fitment took care of some more sophisticated VV T et al which if fully pushed more than obviates the need for AFM /MDS and ta da......... there goes the bigger cube higher FE argument down the drain.


Hopefully, this possible 4.5 has none of two ? of those assumptions in place or involved in any way.

Unless naturally arrived at rather than postulated going in.
 
#149 ·
There is a strong possibility for Cadillac there could be a 4.5 liter twin turbo v8....mr Ackerson and his underlings like Dohc twin turbos for that market segment.

As a buyer I'd prefer the LT1 6.2 liter v8 yet I understand Cadillac must present technology that is perceived as cutting edge....by the public know nothing's...who purchase this segment.


The twin turbo 4.5 Dohc v8 for upcoming Cadillacs will I am sure be powerful..

I'll be content with the corvette maintaining its powerful, light, compact and relatively inexpensive
LT1 and LT4 gen 5 v8 s...
 
#153 ·
There is a strong possibility for Cadillac there could be a 4.5 liter twin turbo v8....mr Ackerson and his underlings like Dohc twin turbos for that market segment.

As a buyer I'd prefer the LT1 6.2 liter v8 yet I understand Cadillac must present technology that is perceived as cutting edge....by the public know nothing's...who purchase this segment.



The twin turbo 4.5 Dohc v8 for upcoming Cadillacs will I am sure be powerful..

I'll be content with the corvette maintaining its powerful, light, compact and relatively inexpensive
LT1 and LT4 gen 5 v8 s...
I agree with you that management might want a DOHC for the Caddy. The 6.2 would be possibly just as good but perception is a powerful thing. I wouldn't say all of those that buy in that class are know nothings but why take the chance of any of them using the excuse that Cadillac don't have a DOHC like Mercedes and the rest of the crowd. Surely the DOHC will cost more to produce but you just charge them accordingly.
 
#163 ·
I personally would like to see GM offer the 6.2L LT1 V8 because it's very powerful and very reliable. The Corvette engines seem to be the best engines that GM currently offers, and I don't see anything wrong with offering the 6.2 as a base engine in their range topping flagship sedan, especially if it produces at least 455 HP and gets good gas mileage.
 
#172 ·
The issue with the Corvette engine is that NVH isn't on par with what's typically installed in top-tier luxury sedans. Reliability, economy, and packaging are excellent but vibrations are excessive for that kind of application.

So, while GM may have one of the world's best V8 engines, it isn't suitable for all tasks.
 
#173 ·
I don't think we will see a 4.5 l v8 DOHC ( or even small displacement OHV ) gasoline engine in Cadillac. Hope I'm wrong.
I don't see GM (Cadillac) developing a new V8 only for Omega vehicle. Escalade already has Ecotec3 6.2 v8 (gen v small block), Cts-v will probably ( rumors suggest) have supercharged version of GEN V (LT4 maybe). ATS-V will have , according to rumors a v6 TT (or LT1).
So only Omega would get a new DOHC V8.
Mercedes put their v8 from C class to S class (rumors are future 4.0 l v8 TT will replace most of the present v8 in their AMG models). Same goes for Audi.
 
#174 ·
In 2008 when The ultra V8 was cancelled, it was scheduled to be introduced In 2009, according to a Motor Trend report. It was stopped because of CAFE and high per unit cost, assuming Buick didn't get a version of it.
A year away means that it still needed work and final testing before it Was released.
It Wouldn't surprise me if it returned in A year or two.
 
#175 ·
It wouldn't surprise you that an engine that would now be about 5 years old, on an uncommon architecture and never once produced in significant quantities would reach production in a year or two? In the Cadillac flagship, no less?

Does GM really strike you as a company to bring products to market engineered YEARS ahead of their time, so well in fact that the product would be able to compete head to head with the best the Germans had to offer for at this rate a full decade or more?
 
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