2.0 liter V6 DI-Turbo

[dwightlooi]

What's worse than a bad product is an undifferentiated product. So, here's an idea for an engine which is not currently available from GM's competitors...

Type: 2.0 liter reverse flow 60-degree V6

Valvetrain: DOHC 4-valves per cylinder, Intake & Exhaust VVT

Construction: Iron Block, Aluminum Heads

Balance Shaft(s): One

Fuel Injection: Common Rail Direct Gasoline Injection

Bore x Stroke: 72.5 x 82.6 mm (Same as 1.4T)

Bore Center: 82 mm

Displacement: 2046 cc

Compression Ratio: 9.3:1

Aspiration: Turbocharged and Intercooled; 1 x Garrett MGT22 Turbocharger

Fuel Type: 87 Octane Unleaded Gasoline

Power Output: 250 bhp @ 5000 rpm

Torque Output: 270 lb-ft @ 1800~4800 rpm

Maximum Engine Speed: 6000 rpm

The idea here is not to build the most powerful engine or the most economical engine. The idea here is to build an engine that is smoother than the typical 3.0~3.6 liter class V6, that has comparable power output and whose low displacement puts it in the same tax bracket as 2.0 liter Inline-4 powerplants in countries with a displacement tax. The engine is smoother by virtue of its low reciprocating mass, relatively short stroke and the presence of a balance shaft (a rarity in 60 deg V6es). For reduced development and production costs, the engine uses the same pistons, valves, springs, connecting rods and combustion chamber geometry as the 1.4 Turbo engine deployed in the Chevy Cruze. The single turbocharger provides responsive power comparable to 3.0 liter V6es with superior torque. Fuel Economy is expected to be similar to 3.0 liter V6es.

Edited January 9, 2011 by dwightlooi

[Drew Dowdell]

Curious, why iron block?

[67impss]

Curious, why iron block?

My thought is its to lower the noise ie dull the high freq. sounds from combustion and timing chain & gear noise

[dwightlooi]

My thought is its to lower the noise ie dull the high freq. sounds from combustion and timing chain & gear noise

Iron is used because the 2.0 is supposed to share components and construction tooling with the Family Zero 1.4 liter four. This engine has very narrow bore spacings making aluminum problematic.

Iron Blocks are not all bad. They are stronger than Aluminum blocks for a given material thickness. This means that the bore centers can be closer and the engine can be smaller. They are also cheaper. This is not so much because iron is cheaper (even though it is), but more because there is no need to have separate iron cylinder liners, Silicon Impregnation of the cylinder walls or Iron Coated Pistons*, hence the manufacturing process is simpler. Iron blocks are also stiffer for a given construct, meaning resonances are moved to a higher frequency making the engine note more refined. In the end, iron is heavier, but that extra 10~20 lbs probably doesn't matter a very much in the overall weight of a 3000+ lbs vehicle.

* You never want to have Aluminum-on-Aluminum frictional contact because frictional coefficients and wear are very high. Hence, Aluminum block engines either have iron liners in the cylinders, iron coated pistons or silicon grains impregnated into the cylinder walls such that (after some of the aluminum wears away during break in) you end up with silicon-aluminum contact.

[regfootball]

Cafe = light powertrains.

Iron block tiny turbo v6 doesn't fit if you can put a four pop on it. Part of the reason the sonata got so light with class leading mpg was they could make the powertrain cradle etc for a four only and didn't need to accomodate a v6

[Drew Dowdell]

Cafe = light powertrains.

Iron block tiny turbo v6 doesn't fit if you can put a four pop on it. Part of the reason the sonata got so light with class leading mpg was they could make the powertrain cradle etc for a four only and didn't need to accomodate a v6

That's because the current class V6 they have that would go into the Sonata is a 3.8 litre DOHC.... basically huge.

What Dwight is proposing is a V6 that is marginally larger than a 4-cylinder that gives substantially better NHV.

Which means, it could go into something like the Sonata and not increase weight dramatically.

[dwightlooi]

That's because the current class V6 they have that would go into the Sonata is a 3.8 litre DOHC.... basically huge.

What Dwight is proposing is a V6 that is marginally larger than a 4-cylinder that gives substantially better NHV.

Which means, it could go into something like the Sonata and not increase weight dramatically.

BTW, a "Reverse Flow" V6 is one where the exhaust exits in the valley of the Vee instead of the outside of the engine. The intake ports are on the outside. This permits a single turbocharger to be used instead of the traditional pair. Larger turbos tend to be more efficient than smaller ones, and one is definitely cheaper and simpler to route than two.

A few example of reverse flow engines are the 6.6 & 4.5 Duramax turbodiesels, the BMW 335d's Diesel V6 and the BMW N63 Turbo V8 in the 2008-present X6 and 750i.

[dwightlooi]

Cafe = light powertrains.

Iron block tiny turbo v6 doesn't fit if you can put a four pop on it. Part of the reason the sonata got so light with class leading mpg was they could make the powertrain cradle etc for a four only and didn't need to accomodate a v6

A 2 liter class V6 is not very big... Here's a 1845cc V6 in a very small car (Mazda MX-3)...

CAFE does not change consumer desire to have the smoothest engine they can buy. In general, especially for cars like a Buick or Cadillac refinement is better selling point than an mpg or two or three. And a selling point that you have, but your competitors do not is more valuable to a salesman than one that is shared with dozens of other vendors.

In any case, I have always been a proponent of ignoring CAFE completely and building cars consumers want to buy and not what the environmental lobby or the political class thinks ought to be sold. CAFE is not a mandated requirement like the airbag laws. CAFE is a fuel economy target which manufacturers have the full freedom to choose to meet or pay a small fine per vehicle for not meeting. The fine is actually quite minimal per vehicle (see below *)

* Let's say CAFE is now at 35 mpg and GM comes in at 31.3 mpg (31.3 mpg is where they are today). By missing by 3.7 mpg, they pay a fine of 37 x $ 5.50 per vehicle sold. That's $203. GM can add that to the price tag if they want. Let's get real, how often is a $20,000 purchase made or broken over $200? Also, GM is free to implement a fairer system of passing on the CAFE penalties. They can make it such that cars not meeting CAFE pays more (say $1 ~ $600 more depending on their consumption) whereas those that do pay nothing. The formula is simple CAFE surcharge = (total CAFE penalty) / [(CAFE requirement - This Vehicle's MPG) / SUM(CAFE requirement - Every Vehicle not meeting CAFE's mpg)]

Then just leave it to the consumer to decide if they want a fuel sipper or high performance vehicle. Then just build as many Volts, as many Cruzes, as many Corvettes and as many Escalades as the market demands -- let CAFE fall where it may and give consumers the choice to pay and pollute if they want or be green and save.

It would be one thing if GM doesn't have a full range of choices should the market sway towards fuel miserly vehicles. But GM is bringing out all the appropriate products to present them with that choice. Now let them choose; don't try to force either 35 mpg or 600 hp down their throats. Let them choose. Doing otherwise is simply bad for business and bad for liberty. Remember, whoever is in the White house do not represent the values of all Americans, at best he represents 40~45%.

Edited January 10, 2011 by dwightlooi

[regfootball]

That's because the current class V6 they have that would go into the Sonata is a 3.8 litre DOHC.... basically huge.

What Dwight is proposing is a V6 that is marginally larger than a 4-cylinder that gives substantially better NHV.

Which means, it could go into something like the Sonata and not increase weight dramatically.

but if its not better at FE in this CAFE environment then there is no point to it.

i can't see a significant enough NVH benefit that some extra sound dampeners and more sophisticated engine isolation couldn't take care of in stead of making 6 cylinders (more weight and rotating mass) push 2 litres of air.

[regfootball]

A 2 liter class V6 is not very big... Here's a 1845cc V6 in a very small car (Mazda MX-3)...

CAFE does not change consumer desire to have the smoothest engine they can buy. In general, especially for cars like a Buick or Cadillac refinement is better selling point than an mpg or two or three. And a selling point that you have, but your competitors do not is more valuable to a salesman than one that is shared with dozens of other vendors.

In any case, I have always been a proponent of ignoring CAFE completely and building cars consumers want to buy and not what the environmental lobby or the political class thinks ought to be sold. CAFE is not a mandated requirement like the airbag laws. CAFE is a fuel economy target which manufacturers have the full freedom to choose to meet or pay a small fine per vehicle for not meeting. The fine is actually quite minimal per vehicle (see below *)

* Let's say CAFE is now at 35 mpg and GM comes in at 31.3 mpg (31.3 mpg is where they are today). By missing by 3.7 mpg, they pay a fine of 37 x $ 5.50 per vehicle sold. That's $203. GM can add that to the price tag if they want. Let's get real, how often is a $20,000 purchase made or broken over $200? Also, GM is free to implement a fairer system of passing on the CAFE penalties. They can make it such that cars not meeting CAFE pays more (say $1 ~ $600 more depending on their consumption) whereas those that do pay nothing. The formula is simple CAFE surcharge = (total CAFE penalty) / [(CAFE requirement - This Vehicle's MPG) / SUM(CAFE requirement - Every Vehicle not meeting CAFE's mpg)]

Then just leave it to the consumer to decide if they want a fuel sipper or high performance vehicle. Then just build as many Volts, as many Cruzes, as many Corvettes and as many Escalades as the market demands -- let CAFE fall where it may and give consumers the choice to pay and pollute if they want or be green and save.

It would be one thing if GM doesn't have a full range of choices should the market sway towards fuel miserly vehicles. But GM is bringing out all the appropriate products to present them with that choice. Now let them choose; don't try to force either 35 mpg or 600 hp down their throats. Let them choose. Doing otherwise is simply bad for business and bad for liberty. Remember, whoever is in the White house do not represent the values of all Americans, at best he represents 40~45%.

GM has already pretty much stated their intent to comply almost universally with CAFE and their products have pretty much shown an intent to depower and downsize across the board. for a company that stole several billion from the taxpayer, they pretty much have to for PR reasons say they will comply with CAFE.

GM is the poster child for trying to save 2 dollars per vehicle either through decontenting, cheaper materials, or many other things repeatedly over decades. Its in GM's DNA to save a penny everywhere they possibly they can think of.

Any money guy the first question they will ask you is why can't i get the same performance out of one of our existing four cylinder lines we already have $$$$$ invested in. then they will ask how the competition can already do it and meet the segment standard without having to create a similar investment in an otherwise non existent powertrain setup.

then they are going to tell you in order to make the program work, you need to put it in XXXXX units at (high cost) and then they will say 'we can't sell enough of those at that price'.

why make it a vee then, just make it an inline engine. a two litre inline six will fit in lots of stuff. the inline 6 is fairly smooth to begin with.

Edited January 10, 2011 by regfootball

[dado]

And then make 4.0 l v12 with 500 hp for ATS-V :smilewide:.

Imagine the lineup

2,0l v6 T with 200 HP

2.0 TT l v6 with 250 HP,

3.0l v6 T with 320 HP

3.0 l v6 TT with 400 HP

4.0 l v12 T with 450 HP

4.0 l v12 TT with 500 HP.

I know GM won't make anything like that not now not in future.But this would make GM different enough. True GM v8 small block also makes GM different from the other companies..but not always in a good way.

[dwightlooi]

but if its not better at FE in this CAFE environment then there is no point to it.

i can't see a significant enough NVH benefit that some extra sound dampeners and more sophisticated engine isolation couldn't take care of in stead of making 6 cylinders (more weight and rotating mass) push 2 litres of air.

I have already explained why I don't think CAFE is that important. Nobody is saying don't build cars that maximizes MPG and meet or exceed CAFE standard. By all means build a full spectrum of them. However, there also exist a very large segment of the market which values other qualities of a vehicle -- refinement, power, etc. -- over the environmental aspirations of the political class. If you want their money, you need give them what they want! And, if nobody else is giving them what they want but you, that's very good for business.

At the end of the day, the market rules.

[dwightlooi]

GM has already pretty much stated their intent to comply almost universally with CAFE and their products have pretty much shown an intent to depower and downsize across the board. for a company that stole several billion from the taxpayer, they pretty much have to for PR reasons say they will comply with CAFE.

...

Any money guy the first question they will ask you is why can't i get the same performance out of one of our existing four cylinder lines we already have $$$$$ invested in. then they will ask how the competition can already do it and meet the segment standard without having to create a similar investment in an otherwise non existent powertrain setup.

...

why make it a vee then, just make it an inline engine. a two litre inline six will fit in lots of stuff. the inline 6 is fairly smooth to begin with.

(1) I believe that GM should build a full range of products covering high performance, high refinement and high economy biases. It should then allow the market to decide if it wants to comply with CAFE or pay the penalties. It won't be a PR problem at all. If consumers make fuel economy the top priority like the political class, all is well. If they don't, GM can point to the Volt, the Cruze and the eAssist Lacrosse and say we have all the fuel efficient products anyone could want, but they are not buying them. And tell the Washington that, perhaps, America does not agree with them. GM's job as a business is not to push any environmental or political agenda, it is to fulfill market demand and turn a profit.

(2) You can meet the power levels with existing 4-cylinder power plants. Actually, you can easily exceed it and do it with better MPG. But that is not the goal. The goal is not to to build the most powerful 2.0 liter engine, the cheapest or the highest MPG. The goal is to surpass the 3.0~3.6 V6 in refinement and get in a lower the displacement tax bracket in some markets. And, in doing so create a differentiated product with no direct competition.

(3) An inline engine will be VERY long. This will make it difficult to employ in transverse applications. In the case of Volvo, they had to make special provisions in their platforms and utilize a fold over transmission design to fit an I6 in their FWD cars. A V6 will basically fit in the current platforms and use the current transmissions.

[Carguy]

These tiny engines are coming! GM has the engines to do something like that today. With the same bore and stroke they could do a lineup like this.

2.0L DI Turbo I4. 260HP 260T.

3.0L DI Turbo V6. 320HP 320T.

3.9L DI Turbo V8. 380HP 380T.

This could be a Cadillac line of engines due to their larger size. Then with differing Bores and strokes they could do a Chevrolet line.

1.5L DI Turbo I4 200HP 220T

2,5L DI Turbo V6 260HP 280T

And so on. Buick could be.

1.8L DI Turbo I4 225HP 240T

2.8L DI Turbo V6 285HP 300T

3.8L DI Turbo V8 345HP 360T.

I would like to see different engine lines for the main stream GM sedans done like this both related yet different from one another. Trucks and Muscle/Sports cars could be larger then these yet smaller with DI and Turbo then today's SB V8's

[regfootball]

I have already explained why I don't think CAFE is that important. Nobody is saying don't build cars that maximizes MPG and meet or exceed CAFE standard. By all means build a full spectrum of them. However, there also exist a very large segment of the market which values other qualities of a vehicle -- refinement, power, etc. -- over the environmental aspirations of the political class. If you want their money, you need give them what they want! And, if nobody else is giving them what they want but you, that's very good for business.

At the end of the day, the market rules.

how do you explain stuff like skip shift on corvettes then.

GM will go to great lengths to meet regulations imposed. Even if the market probably doesn't want it in some situations.

[regfootball]

(1) I believe that GM should build a full range of products covering high performance, high refinement and high economy biases. It should then allow the market to decide if it wants to comply with CAFE or pay the penalties. It won't be a PR problem at all. If consumers make fuel economy the top priority like the political class, all is well. If they don't, GM can point to the Volt, the Cruze and the eAssist Lacrosse and say we have all the fuel efficient products anyone could want, but they are not buying them. And tell the Washington that, perhaps, America does not agree with them. GM's job as a business is not to push any environmental or political agenda, it is to fulfill market demand and turn a profit.

(2) You can meet the power levels with existing 4-cylinder power plants. Actually, you can easily exceed it and do it with better MPG. But that is not the goal. The goal is not to to build the most powerful 2.0 liter engine, the cheapest or the highest MPG. The goal is to surpass the 3.0~3.6 V6 in refinement and get in a lower the displacement tax bracket in some markets. And, in doing so create a differentiated product with no direct competition.

(3) An inline engine will be VERY long. This will make it difficult to employ in transverse applications. In the case of Volvo, they had to make special provisions in their platforms and utilize a fold over transmission design to fit an I6 in their FWD cars. A V6 will basically fit in the current platforms and use the current transmissions.

GM would never invest in an odd duck like a 2.0 six if they can't market and sell it here in the US, and in the USA a 2.0 6 would be met with a collective 'wtf' by car buyers. There would not be enough of a market outside the US to do it.

[67impss]

GM would never invest in an odd duck like a 2.0 six if they can't market and sell it here in the US, and in the USA a 2.0 6 would be met with a collective 'wtf' by car buyers. There would not be enough of a market outside the US to do it.

How do you figure that they build Euro spec engines now and where do you think the 2.8 & 3.0L HF engines were developed? Then there's the Diesel program as of now Euro only. Small engines for Asia & India that aren't sold in North America soooooo, this concept could work if GM starts shifting to Global Marketing as Ford is employing at this very minute

[dwightlooi]

how do you explain stuff like skip shift on corvettes then.

GM will go to great lengths to meet regulations imposed. Even if the market probably doesn't want it in some situations.

I am not saying that they won't or that they haven't. I am saying that they shouldn't.

Making annoying decisions like these and making unwise decisions like concentrating heavily on one segment of demand (like big SUVs in the 90s) make for bad business that led to GM's downfall. Making "Green" decisions that pander to the political class and environmental lobbies and ignoring what a large chunk of consumers really want is equally bad and may play out to become the folly of the new millenium.

[regfootball]

Dwight you'd be surprised to know that I pretty much agree with what you are saying about that, I just don't think companies like GM have the balls to do it to go against the grain anymore. The media is too present to mock them, and after all, there is the issue of the bailout.....

I am sure there are those within GM who have the fighting and creative and aggressive spirit. There are so many levels of garbage socially and regulatory these days that taking anything resembling any kind of risk these days will become increasingly rare, especially once the financial folks weigh in.

I know your premise was based on the notion that this would be a good application in those markets where displacement is taxed. But just putting myself in the mind of a bean counter who would say 'well don't we already have a turbocharged 2 litre engine that we already have plant money and r & D money invested in that could do the job just as well'?

Here is a little bit of the same mentality. GMC Terrain has the company 4 banger engine. Instead of designing that powertrain to be more refined, they add the noise cancellation thing. Now maybe they wanted to pursue that technology anyways. But I wonder if the beancounters don't appreciate that you can just 'tack on' something like that to give the impression of refinement instead of redesigning a new powertrain which may help reduce that issue inherently.

I really like your idea with all the different engine configs and that to me is what is refreshing. I guess after being a GM fan and a car fan for so long I have all this pent up pessimism because so many of the good ideas don't get the exploration that they should.

Here is a perfect example of that. That light duty diesel truck motor. Now i know its almost production ready, it got that far. But now my sense is that it will never see the showroom floor.....when really it is exactly the type of thing GM could use and sell big in its pickups right now.

I'd like to see GM get into a boxer engine but GM's fanbase wouldn't really dig it. I'd also like to see a GM version of the CRX, I'd also like to see a new age Fiero.

Edited January 11, 2011 by regfootball

[dwightlooi]

Here is a perfect example of that. That light duty diesel truck motor. Now i know its almost production ready, it got that far. But now my sense is that it will never see the showroom floor.....when really it is exactly the type of thing GM could use and sell big in its pickups right now.

3.3 Liter Inline-4, IBC Pushrods, 4-valves per cylinder, Direct Injection -- sharing the rods, pistons, valves, etc with the Duramax 6.6?

Should be good for about 200 hp @ 3200 rpm and 380 lb-ft @ 1600 rpm.

Not bad for a light truck like the Colorado or Canyon, especially if paired with the 6L80 6-speed auto.

With a pair of balancer shafts and given the lowish redline, its probably not even that bad in civility.

[regfootball]

i was thinking of that 4.5 litre duramax v8 diesel with the reverse intake setup?

[dwightlooi]

i was thinking of that 4.5 litre duramax v8 diesel with the reverse intake setup?

The 4.5 IS a reverse flow engine to begin with. It is also a 72 degree V8 -- that rather than the reverse flow setup is a first for a V8. Development on the engine was basically completed in 2008. The introduction was canceled due to the bankruptcy and preceding upheavals.

You can probably make a 150~160hp / 260~280 lb-ft four potter by chopping it in half.

[dado]

These tiny engines are coming! GM has the engines to do something like that today. With the same bore and stroke they could do a lineup like this.

2.0L DI Turbo I4. 260HP 260T.

3.0L DI Turbo V6. 320HP 320T.

3.9L DI Turbo V8. 380HP 380T.

This could be a Cadillac line of engines due to their larger size. Then with differing Bores and strokes they could do a Chevrolet line.

1.5L DI Turbo I4 200HP 220T

2,5L DI Turbo V6 260HP 280T

And so on. Buick could be.

1.8L DI Turbo I4 225HP 240T

2.8L DI Turbo V6 285HP 300T

3.8L DI Turbo V8 345HP 360T.

I would like to see different engine lines for the main stream GM sedans done like this both related yet different from one another. Trucks and Muscle/Sports cars could be larger then these yet smaller with DI and Turbo then today's SB V8's

Yes I4 and v6 are coming. But not V8 with that displacement. Rumors are there will be two displacement of GEN V. 5.3 l and 6.2 l, and only 6.2 l will have forced induction (most probably supercharger). So for 350-400 HP GM will probably use 3.0 l v6 TT (also a rumor to be in development). Too bad . I would like to see a small displacement V8 from GM (something like old 3.5 l v8)

Edited January 11, 2011 by dado

[67impss]

You are remembering the Buick/Olds 215 aluminum sold to Rover right?

[Drew Dowdell]

The 4.5 IS a reverse flow engine to begin with. It is also a 72 degree V8 -- that rather than the reverse flow setup is a first for a V8. Development on the engine was basically completed in 2008. The introduction was canceled due to the bankruptcy and preceding upheavals.

You can probably make a 150~160hp / 260~280 lb-ft four potter by chopping it in half.

Which half of the turbo do I keep? The exhaust half or the intake half? ;-)

[dado]

You are remembering the Buick/Olds 215 aluminum sold to Rover right?

Yup..it had about 145 kg. I mean if we want engine which would make product different enough from others then 2.0l v6, 3,5 T v8, etc wouldn't be such a bad idea. Of course GM probably doesn't have money for such projects.

[regfootball]

hows about an oval pistion "v-4" with 32 valves? (Honda) that would be an interesting small displacment configuration although I am sure that doesn't really adress the smoothness issue.

[67impss]

hows about an oval pistion "v-4" with 32 valves? (Honda) that would be an interesting small displacment configuration although I am sure that doesn't really adress the smoothness issue.

What a machining nightmare that would be, not so bad on a rotary engine as the chambers are sliced sections that are shallow but a block with even 3.5" deck height would be a mess. Hard to comprehend the machining process even from my background maybe dwightlooi has seen something like that HELL I can't even think how to get crosshatch to get the rings seated

[67impss]

Per Wiki

"Honda's NR (New Racing) V-four motorcycle engine series started in 1979 with the 500cc NR500 Grand Prix racer that used oval pistons.[1] This was followed during the 1980s by a 750cc endurance racer version known as the NR750. The oval piston concept allowed for eight valves per cylinder which generated more power due to the increased air/fuel mixture throughput and compression. In 1992 Honda produced around 300 street versions of a 750cc model, the NR (often mistakenly referred to as the NR750), with a 90-degree V angle. Whereas the NR500 had used an oval piston with straight sides, the road going NR750 used an elliptical piston with curved long sides. The bike became the most expensive production bike at the time when it was selling for $50,000 and with the rarity, nowadays they rarely change hands."

Now do you see any make producing 100K units of this type a year? I think not there isn't a business out there to bring this to fruition.

[dwightlooi]

Yes I4 and v6 are coming. But not V8 with that displacement. Rumors are there will be two displacement of GEN V. 5.3 l and 6.2 l, and only 6.2 l will have forced induction (most probably supercharger). So for 350-400 HP GM will probably use 3.0 l v6 TT (also a rumor to be in development). Too bad . I would like to see a small displacement V8 from GM (something like old 3.5 l v8)

I hope they keep it simple and stick to one displacement. A 5.3 will not have significant fuel economy advantage over a 6.2 and the ower bracket servved by the 5.3 is probably better served by a 4.6 90 deg pushrod V6 of (300~315 hp) derived from the 6.2.

[loki]

I hope they keep it simple and stick to one displacement. A 5.3 will not have significant fuel economy advantage over a 6.2 and the ower bracket servved by the 5.3 is probably better served by a 4.6 90 deg pushrod V6 of (300~315 hp) derived from the 6.2.

assuming GM wants to keep a pushrod v6 in anything... if not, your idea is in vain....

but anyway.

[dado]

I hope they keep it simple and stick to one displacement. A 5.3 will not have significant fuel economy advantage over a 6.2 and the ower bracket servved by the 5.3 is probably better served by a 4.6 90 deg pushrod V6 of (300~315 hp) derived from the 6.2.

But then chevrolet Corvette, Cadillac, Holden, Chevy and GMC truck will all have one engine(maybe different in top version where supercharger will be used).IMO not good(not enough difference inside firm). Maybe good for Chevy and Holden. But not for Cadillac.

If they make lower engine (2.0 l v6) to be different from the other carmakers(Mercedes, Audi , Hyundai, Toyota) why not make some special top engines. I mean instead of 2.8 l v6 in Opel Insignia OPC make 2.8 l v8(I'm from Europe and 2.8 l V6 is top engine in Opel cars here and since Opel is division of GM...). Or 5.7 l TT V8 for Cadillac..or smaller 4.5 L v12 TT.

[dwightlooi]

assuming GM wants to keep a pushrod v6 in anything... if not, your idea is in vain....

but anyway.

Well, they are keeping a Pushrod V8 for sure. This leaves three possibilities..

Use a smaller displacement V8 in the 300~330 hp bracket in the entry level big Trucks and SUVs, use a 4.6 liter Pushrod V6 of similar output or use the 3.6 DOHC V6.

The 3.6 DI engine is really ill suited for the role with a 5200 rpm torque peak, only 270~278 lb-ft of twist and probably higher costs. A 4.8 or 5.3 V8 is smoother but also higher consumption. A 4.6 Pushrod V6 will have enough torque, a low enough torque peak and better fuel economy. As far as refinement goes, it'll be OK but not stellar. If the customer cares that much but this, they can order the 6.2 V8 option.

A 4.6 Pushrod V6 is also arguably a better engine for the Caprice PPV or the Camaro V6 than the 3.6 DOHC.

[dwightlooi]

But then chevrolet Corvette, Cadillac, Holden, Chevy and GMC truck will all have one engine(maybe different in top version where supercharger will be used).IMO not good(not enough difference inside firm). Maybe good for Chevy and Holden. But not for Cadillac.

If they make lower engine (2.0 l v6) to be different from the other carmakers(Mercedes, Audi , Hyundai, Toyota) why not make some special top engines. I mean instead of 2.8 l v6 in Opel Insignia OPC make 2.8 l v8(I'm from Europe and 2.8 l V6 is top engine in Opel cars here and since Opel is division of GM...). Or 5.7 l TT V8 for Cadillac..or smaller 4.5 L v12 TT.

This is how I'll position the various versions...

Basically, only the Vette and Cadillac will get the high performance, high compression, independent VVT, premium fuel version. Everybody else will use the Vortec.

[NOS2006]

but if its not better at FE in this CAFE environment then there is no point to it.

i can't see a significant enough NVH benefit that some extra sound dampeners and more sophisticated engine isolation couldn't take care of in stead of making 6 cylinders (more weight and rotating mass) push 2 litres of air.

The rotating mass wouldn't be that much more. The pistons would each be smaller in the 2.0 V6 than a 2.0 I4. Overall, I think the mass of the 6 pistons (+ 2 extra connecting rods) would only be slightly heavier than the I4. Not necessarily negligible, but also not necessarily too much to argue over.

[regfootball]

yeah but at two litres, anything that stifles maximizing the effects of your combustion........