Should GM build a "Premium" version of the LT1 for Cadillac?

[dwightlooi]

LT5 Premium V8 (hypothetical)

The LT1 is a more than competitive engine for the Corvette and other GM vehicles. But, certain feature decisions pertaining to the LT1 were made to strike an optimal balance between costs and benefitsfor a wide array of applications – decisions which may or may not be optimal for Luxury Performance cars which are less price sensitive. Should a premium version of the LT1 be developed – every much like the LS6 was the to LS2 and the LS7 was to the LS3? Such an engine may fit well into the Cadillac lineup.

Features Added over LT1

• 104.8 mm bore x 102 mm stroke (7.0 liters displacement)
  
• Cam-in-cam independent intake & exhaust VVT
  
• 2-stage valve lift control via concentric intake and exhaust lifters
  
• Titanium intake valves
  
• Titanium pushrods
  
• Titanium connecting rods
  
• Double wall 4:1 headers
  
• Magnesium Structural Oil Pan
  
• Magnesium valve covers
  
• Trumpeted velocity stacks in air box with 8 linked throttle butterflies
  
• Dry Sump lubrication (standard)
  
• Raised Compression Ratio (12.2:1)
  
• Increased Maximum Engine speed (7100 rpm)
  
• Premium 91 Octane Fuel Required
  

Features Deleted from LT1

• AFM Cylinder Deactivation (AFM lifters replaced by VVL lifters)
  

Performance

• 550 bhp @ 6800 rpm
  
• 512 lb-ft @ 4800 rpm
  
• Redline @ 7000 rpm
  
• Fuel cut @ 7100 rpm
  

Porsche Variocam Plus lifters -- the VVL pushrod lifters will be similar in design except for the location of the camshaft.

Edited October 26, 2012 by dwightlooi

[CanadianBacon94]

Unfortunately, you drive to make engines 91 octane standard doesn't pan out it the real world, as the manufacturers are scared of what happened with that Caddy SRX 2.8, and other uninformed buyer.

[FAPTurbo]

NOT DOHC. NOT CARING. 0/10000 GM.

SIGNED,

- TEH INTERNETS

[Z-06]

Unfortunately, you drive to make engines 91 octane standard doesn't pan out it the real world, as the manufacturers are scared of what happened with that Caddy SRX 2.8, and other uninformed buyer.

LS7 is premium required.

[dwightlooi]

91 Octane required does not mean the engine will blow up if you pump 87 octane in the tank. It practically never happens.

What happens is that the engine losses a significant amount of power, will probably fail emissions tests and may go into a limp mode (limiting throttle opening) if you pump 87 octane in the tank. Knock usually happens at high load, low rpms. And, the immediate remedy by the ECU is usually to go rich on the fuel-air ratio. Go rich enough and you can run 14:1 compression on 85 octane. It just means that power goes down, fuel consumption goes up and hydrocarbon emissions can go through the roof. If you do it for years on end you plug up the cat converter too, but this won't happen even with a few tanks of gas and when you lean back up the stuff tends to burn away in over time anyway.

There is no EPA or CARB requirement that a vehicle pass SMOG on the wrong fuel, so the emissions part is a non issue for certification purposes.

Edited October 27, 2012 by dwightlooi

[smk4565]

Premium fuel and synthetic oil is no big deal for a luxury car, all the German cars require it and people keep buying them.

What would you put this engine in though? CTS-V? A Cadillac flagship sedan has to register around 60 dBA at 70 mph, hard for a pushrod engine to do that. Even the Bentley Mulsanne and Brooklands with all their sound deadening run 65-67 DBA, while Rolls Royce Ghost is 63 and the Phantom is 59. The CTS-V is over 70 dba at 70 mph, too noisy to go head to head with an S-class.

Bentley is dropping the pushrod also in favor of DOHC for all models. That would leave Cadillac with the engine out of a Corvette/Camaro or Charger, while every other luxury car has something else. Hard to convince the masses why Cadillac is right and 12 other car companies that people pay high premiums for are wrong.

[dwightlooi]

Premium fuel and synthetic oil is no big deal for a luxury car, all the German cars require it and people keep buying them.

What would you put this engine in though? CTS-V? A Cadillac flagship sedan has to register around 60 dBA at 70 mph, hard for a pushrod engine to do that. Even the Bentley Mulsanne and Brooklands with all their sound deadening run 65-67 DBA, while Rolls Royce Ghost is 63 and the Phantom is 59. The CTS-V is over 70 dba at 70 mph, too noisy to go head to head with an S-class.

Bentley is dropping the pushrod also in favor of DOHC for all models. That would leave Cadillac with the engine out of a Corvette/Camaro or Charger, while every other luxury car has something else. Hard to convince the masses why Cadillac is right and 12 other car companies that people pay high premiums for are wrong.

I don't believe the Pushrod configuration or the DOHC configuration affects the noise level. The valve train doesn't make any more or less noise. If you want to cut down on noise and improve refinement you may want to consider doing things like going back to port injection or better yet carburetion, or dropping compression ratio. If you pull all the cost and complexity concerns out of the equation, you may do what Lexus does --use both Port Injection and Direction Injection. Port injection for a quiet idle and cruise refinement, Direct injection cutting in at when maximum power is called for.

Dropping displacement makes the engine less noisy at any given rpm. But it also increases you minimum cruising rpms due to reduced torque.

Edited October 27, 2012 by dwightlooi

[hyperv6]

This is nothing new here. Many of us have already stated GM needs a specail V8 for the new flag ship sedan and what ever variation they may come up with.

At this point it really matter little if it is a DOHC or based on the LT1 The one key element is that it can not just be some engine plucked from the Pick up trucks or Corvette As I have stated here many times it needs to have it's own tune and set up. Also it needs to be dressed up and with real polished/powdercoated aluminum and stainless bits and not just have some plastic cover slapped over it.

If you want a car to be more you have to give it more. Also you want Cadillac to be more than a fancy Chevy you need to give them more or something different. So far the cars have been doing that with the ATS and CTS now it is time for the engines to start doing the same starting with the LTS.

Anything less than a specificCadillac tuned and dressed engine in the LTS will be a mistake. If you want the car to be special then damn well make it special.

I think they dropped the ball on the Eco Turbo in the ATS as they should have given it more power and torque vs the GS.

[Carguy]

Interesting idea! But if you are to change out all those parts who not just develope some DOHC 4VPC DI heads? Or even better yet just take the Altra V8 off the shelf and Turbo Charge it for modern Cadillac use! Cadillac truly needs and deserves its own DOHC V8!

[dado]

If GM doesn't offer DOHC v8 (or maybe 3 valve heads on LT version for Cadillac) than this is a least they should offer in premium cadillac model. But i doubt we will see a 7.0 LT version. A 6.2 l supercharger is probably the best and biggest LT GM will have in their LT portfolio.

[smk4565]

What Cadillac really needs is a new transmission. 6-speeds are old news in the luxury market, they should have 8-10, that makes you not need huge engine for quiet highway cruise. Especially in the wake of them pulling the 6-speed manual since every car magazine bashed it. They need a new manual, might as well replace the automatic too. And the 2.0T ATS is slow, not sure if that is the transmission's fault of not, probably is.

I still believe Cadillac needs their own DOHC V8, and they should have a Cadillac only turbo or supercharged V6. Audi and Jaguar both have 3.0 liter supercharged V6s, Hyundai is working on a twin turbo 3 liter V6, BMW has a twin turbo six, so it seems like the boosted 3 liter with low end torque paired with an 8-speed is the hot item for mid-range luxury cars. On the top end, you need a V8 though.

[hyperv6]

The transmissions are coming as GM and Ford have joined forces for them. The TT V6 will mostly be used in the Cadillacs for the most part. As of now I would be suprised if they are used in anything else than the Camaro and maybe a C8 or later Vette.

The TT V6 will not be in the Impala or Malibu or any other Buick at this point. That could change but GM is not saying any more.

[dwightlooi]

Interesting idea! But if you are to change out all those parts who not just develope some DOHC 4VPC DI heads? Or even better yet just take the Altra V8 off the shelf and Turbo Charge it for modern Cadillac use! Cadillac truly needs and deserves its own DOHC V8!

The LT1, for all it's merits, is already over weight. 211 kg vs 183 kg for the LS3 (15% gain in mass). If you switch to DOHC heads the engine gets even heavier (possibly around 240 kg). DOHC heads also make the engine taller and wider. Most importantly though, DOHC heads make the engine less fuel efficient by increasing the internal friction -- four times as many camshafts, twice as many lobes and much greater bearing surfaces in the valve train.

As far as the new autos go, they won't arrive for another 2~3 years.

Edited October 28, 2012 by dwightlooi

[dado]

Interesting idea! But if you are to change out all those parts who not just develope some DOHC 4VPC DI heads? Or even better yet just take the Altra V8 off the shelf and Turbo Charge it for modern Cadillac use! Cadillac truly needs and deserves its own DOHC V8!

The LT1, for all it's merits, is already over weight. 211 kg vs 183 kg for the LS3 (15% gain in mass). If you switch to DOHC heads the engine gets even heavier (possibly around 240 kg). DOHC heads also make the engine taller and wider. Most importantly though, DOHC heads make the engine less fuel efficient by increasing the internal friction -- four times as many camshafts, twice as many lobes and much greater bearing surfaces in the valve train.

As far as the new autos go, they won't arrive for another 2~3 years.

Twin turbo 5.5 l,560+ hp, v8 DI DOHC v8 from Mercedes (m 157)- 204 kg

6.2 l v8 DOHC v8 from Mercedes , 570 hp (M159)- around 200 kg.

BMW 4.4 v8 DOHC twin turbo DI ,from 400- 550+ hp- around 220 kg

Viper v10 8,4 l 640 hp, ohv-around 220 kg

Coyote v8, 440 hp, DOHC -around 200 kg

Now put a supercharger on the LT1 (i doubt GM will increase displacement on this one) to have competitive HP&torque rating and you have an engine with over 220 kg and more. Now when small block has lost advantage on weight and if i have read correctly it is getting bigger in dimensions too (but still not as big as DOHC competition) ,i think GM should think about special engine for Cadillac premium vehicles.

I can see even a coyote v8 with supercharger or twin turbocharger having less weight than a LT1 (LT4).

Edited October 28, 2012 by dado

[smk4565]

The transmissions are coming as GM and Ford have joined forces for them. The TT V6 will mostly be used in the Cadillacs for the most part. As of now I would be suprised if they are used in anything else than the Camaro and maybe a C8 or later Vette.

Weren't the transmissions for FWD cars only? Or was there to be a rear drive version as well?

[hyperv6]

The transmissions are coming as GM and Ford have joined forces for them. The TT V6 will mostly be used in the Cadillacs for the most part. As of now I would be suprised if they are used in anything else than the Camaro and maybe a C8 or later Vette.

Weren't the transmissions for FWD cars only? Or was there to be a rear drive version as well?

From my understanding there were going to be both.

[G. David Felt]

I think this could work for Caddy once they address the other needs in the product line.

[ZL-1]

Well, GM did this with the current Z06 engine, right? IIRC it's a 7.0L hand built version of the smallblock... So doing it for Cadillac could be achieavable. Can't comment on the technical aspects of the engine though...

Edited October 30, 2012 by ZL-1

[dwightlooi]

The transmissions are coming as GM and Ford have joined forces for them. The TT V6 will mostly be used in the Cadillacs for the most part. As of now I would be suprised if they are used in anything else than the Camaro and maybe a C8 or later Vette.

Weren't the transmissions for FWD cars only? Or was there to be a rear drive version as well?

Both.

[dwightlooi]

Interesting idea! But if you are to change out all those parts who not just develope some DOHC 4VPC DI heads? Or even better yet just take the Altra V8 off the shelf and Turbo Charge it for modern Cadillac use! Cadillac truly needs and deserves its own DOHC V8!

The LT1, for all it's merits, is already over weight. 211 kg vs 183 kg for the LS3 (15% gain in mass). If you switch to DOHC heads the engine gets even heavier (possibly around 240 kg). DOHC heads also make the engine taller and wider. Most importantly though, DOHC heads make the engine less fuel efficient by increasing the internal friction -- four times as many camshafts, twice as many lobes and much greater bearing surfaces in the valve train.

As far as the new autos go, they won't arrive for another 2~3 years.

Twin turbo 5.5 l,560+ hp, v8 DI DOHC v8 from Mercedes (m 157)- 204 kg

6.2 l v8 DOHC v8 from Mercedes , 570 hp (M159)- around 200 kg.

BMW 4.4 v8 DOHC twin turbo DI ,from 400- 550+ hp- around 220 kg

Viper v10 8,4 l 640 hp, ohv-around 220 kg

Coyote v8, 440 hp, DOHC -around 200 kg

Now put a supercharger on the LT1 (i doubt GM will increase displacement on this one) to have competitive HP&torque rating and you have an engine with over 220 kg and more. Now when small block has lost advantage on weight and if i have read correctly it is getting bigger in dimensions too (but still not as big as DOHC competition) ,i think GM should think about special engine for Cadillac premium vehicles.

I can see even a coyote v8 with supercharger or twin turbocharger having less weight than a LT1 (LT4).

Dimensionally I don't believe it has grown. If anything the runner in box plenum is shorter in height than the current runner design. The engine is heavy though compared to the LS3 183-> 211 kg represents a 15% weight growth. That's a lot considering that there is no displacement growth and no bore spacing changes.

[hyperv6]

The transmissions are coming as GM and Ford have joined forces for them. The TT V6 will mostly be used in the Cadillacs for the most part. As of now I would be suprised if they are used in anything else than the Camaro and maybe a C8 or later Vette.

Weren't the transmissions for FWD cars only? Or was there to be a rear drive version as well?

Both.

Is there an echo in here? LOL!

[dado]

Would this premium V8 LT1 be top engine for Cadillac?

Even if we are looking at a present V8 engines this "premium" version of LT1 is behind in torque,HP and weight. Just take a look at 5.5 l v8 TT (m157) from Mercedes. This type of a engine is what will future engine in Cadillac compete against. And not just in flagships. GM can make a DOHC v8,v12,v10 etc. but if it isn't better or equal to a engines from competition GM would be wasting time and money for nothing.

I also think LT1 version like 6.2 l v8 with turbochargers (maybe even a different displacement) would be a better choise for premium Cadillac. Also more important question is will GM be able to show this premium v8 as genuine Cadillac engine and not something which is shared with cheaper cars and trucks.

Edited November 1, 2012 by dado

[dwightlooi]

Would this premium V8 LT1 be top engine for Cadillac?

Even if we are looking at a present V8 engines this "premium" version of LT1 is behind in torque,HP and weight. Just take a look at 5.5 l v8 TT (m157) from Mercedes. This type of a engine is what will future engine in Cadillac compete against. And not just in flagships. GM can make a DOHC v8,v12,v10 etc. but if it isn't better or equal to a engines from competition GM would be wasting time and money for nothing.

I also think LT1 version like 6.2 l v8 with turbochargers (maybe even a different displacement) would be a better choise for premium Cadillac. Also more important question is will GM be able to show this premium v8 as genuine Cadillac engine and not something which is shared with cheaper cars and trucks.

An engine like this will fit in as the "Standard V8" for Caddy. Probably as the top engine on the ATS and the run of the mill V8 for the SLS or whatever they chose to call the large sedan. The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

[dado]

The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

Don't forget what top engine does the S class has.It is a twin turbo v12. So this supercharged v8 (if cadilac flagship will go against s class) must not be noisier (no supercharger whine in cabin) than the engine in the S class,Or at least is must not be heard in a cabin .Actually NVH should be on same level.

[smk4565]

Audi, BMW and Mercedes all sell 12 cylinder in their top end car. Porsche, Jaguar and Maserati go with a V8 though, so Cadillac could go the V8 route. Thing is, notice that the M3 V8 isn't used in a 5-series, the M5 V8 not used in the 7-series, the C63 AMG engine not found in an S-class, etc. The current CTS-V engine lacks the NVH needed for a flagship sedan, a CTS-V at 70 mph cruise is louder than the base V6 model. So it isn't as simple as saying the ATS-V or CTS-V engine can be put into a flagship sedan, Cadillac almost needs 2 different V8s.

[balthazar]

>>"CTS-V at 70 mph cruise is louder than the base V6 model"<<

So is the M3 over the base model, and the M5 over the base model. That is how this class is engineered, purposely.

Non-point.

[G. David Felt]

The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

Don't forget what top engine does the S class has.It is a twin turbo v12. So this supercharged v8 (if cadilac flagship will go against s class) must not be noisier (no supercharger whine in cabin) than the engine in the S class,Or at least is must not be heard in a cabin .Actually NVH should be on same level.

Why do you and so many others think everything has to go against and be equal to the S class. I have not been that impressed myself with the over all quality of Mercedes. I think right now both MB and BMW have over bloated images. It proves in the JD quality reports and so many times in the real world, not the auto motive blind journalism.

I would be more focused on what high end customers really want than to say MB or BMW is our check list. Are we equal to or better than them?

Use a customer input list and build to what the customer wants, if it really ends up being equal to MB or BMW, then so be it, but at least then GM is building to the customer. Once built, then compare and see how you stack up.

>>"CTS-V at 70 mph cruise is louder than the base V6 model"<<

So is the M3 over the base model, and the M5 over the base model. That is how this class is engineered, purposely.

Non-point.

Totally agree, people who are buying the AMG, M series or V series are wanting the performance rumble. They do not want these cars to be quiet non noticable cars.

[dado]

Why do you and so many others think everything has to go against and be equal to the S class. I have not been that impressed myself with the over all quality of Mercedes. I think right now both MB and BMW have over bloated images. It proves in the JD quality reports and so many times in the real world, not the auto motive blind journalism.

I would be more focused on what high end customers really want than to say MB or BMW is our check list. Are we equal to or better than them?

Use a customer input list and build to what the customer wants, if it really ends up being equal to MB or BMW, then so be it, but at least then GM is building to the customer. Once built, then compare and see how you stack up.

And what do you think high end customer wants? Cars that are worse than s class, A8,7 or better than S class, A8, 7?

Few days ago GM announce that it will rise price and prestige of Cadillac cars to be better align with german cars. Why do you think they will do that? Why does GM wants Cadillac to go against Germans cars in luxury class if there are better cars out there? If Cadillac wants to be taken seriously in luxury car market they will have to be better than other cars in that market..And that cars are coming from Mercedes, BMW, Audi. Not Volvo, Lincoln, Acura.

Also Cadillac is way behind on image in Europe. And it seems that it lack in image in USA too. Does Mercedes and BMW have over bloated image..Yes. But this is something Cadillac will go against on most markets in the world. So maybe if they build cars that are better than S class or A8 (but i think S class is still being considered king in its class...not to mention there is new one coming soon..but maybe i'm wrong), their image will go up. And maybe after time Cadillac will be considered Standard of the world again.

Regarding J.D quality report...there is also J.D. Power 2012 Vehicle Ownership Satisfaction Study and according to this study Mercedes-Benz drivers are the most satisfied. I found this by just typing mercedes benz and J.D. Power.

I'm curious is there any category where Cadillac has taken first place in J.D power regarding their cars(best premium cars, most reliable or anything regarding their cars)?

Edited November 5, 2012 by dado

[dwightlooi]

Audi, BMW and Mercedes all sell 12 cylinder in their top end car. Porsche, Jaguar and Maserati go with a V8 though, so Cadillac could go the V8 route. Thing is, notice that the M3 V8 isn't used in a 5-series, the M5 V8 not used in the 7-series, the C63 AMG engine not found in an S-class, etc. The current CTS-V engine lacks the NVH needed for a flagship sedan, a CTS-V at 70 mph cruise is louder than the base V6 model. So it isn't as simple as saying the ATS-V or CTS-V engine can be put into a flagship sedan, Cadillac almost needs 2 different V8s.

A Pushrod engine is not inherently louder than a DOHC engine. The CTS-V is loud because it was decided that a pretty loud exhaust is OK, perhaps even desirable.

[smk4565]

My point to the CTS-V being loud, is that the CTS-V engine can't be used in a flagship sedan. So Cadillac needs a V8 for performance, and a different V8 that is quiet. Just like the M3 V8 wouldn't work in a 7-series. So taking the CTS-V or ZR1 engine or slapping a turbo on the LS1 I don't see as a viable plan for a big luxury sedan.

To dfelt's point as to building what the customer wants, the S-class has been the best selling large luxury car in the world over the past 30 years, so it seems like that is what they want.

[Z-06]

Why do you and so many others think everything has to go against and be equal to the S class. I have not been that impressed myself with the over all quality of Mercedes. I think right now both MB and BMW have over bloated images. It proves in the JD quality reports and so many times in the real world, not the auto motive blind journalism.

I would be more focused on what high end customers really want than to say MB or BMW is our check list. Are we equal to or better than them?

Use a customer input list and build to what the customer wants, if it really ends up being equal to MB or BMW, then so be it, but at least then GM is building to the customer. Once built, then compare and see how you stack up.

And what do you think high end customer wants? Cars that are worse than s class, A8,7 or better than S class, A8, 7?

Few days ago GM announce that it will rise price and prestige of Cadillac cars to be better align with german cars. Why do you think they will do that? Why does GM wants Cadillac to go against Germans cars in luxury class if there are better cars out there? If Cadillac wants to be taken seriously in luxury car market they will have to be better than other cars in that market..And that cars are coming from Mercedes, BMW, Audi. Not Volvo, Lincoln, Acura.

Also Cadillac is way behind on image in Europe. And it seems that it lack in image in USA too. Does Mercedes and BMW have over bloated image..Yes. But this is something Cadillac will go against on most markets in the world. So maybe if they build cars that are better than S class or A8 (but i think S class is still being considered king in its class...not to mention there is new one coming soon..but maybe i'm wrong), their image will go up. And maybe after time Cadillac will be considered Standard of the world again.

Regarding J.D quality report...there is also J.D. Power 2012 Vehicle Ownership Satisfaction Study and according to this study Mercedes-Benz drivers are the most satisfied. I found this by just typing mercedes benz and J.D. Power.

I'm curious is there any category where Cadillac has taken first place in J.D power regarding their cars(best premium cars, most reliable or anything regarding their cars)?

That is the European study. Cadillac was behind Lexus and Toyota for 2009 U.S. long-term vehicle reliability ahead of all the Germans.

[dwightlooi]

My point to the CTS-V being loud, is that the CTS-V engine can't be used in a flagship sedan. So Cadillac needs a V8 for performance, and a different V8 that is quiet. Just like the M3 V8 wouldn't work in a 7-series. So taking the CTS-V or ZR1 engine or slapping a turbo on the LS1 I don't see as a viable plan for a big luxury sedan.

To dfelt's point as to building what the customer wants, the S-class has been the best selling large luxury car in the world over the past 30 years, so it seems like that is what they want.

Actually, the CTS-V V8 is quite suitable for a flagship -- if it is fitted with the appropriate exhaust system that does not make a lot of noise. The LSA is a smooth and tractable engine with a 6100 rpm redline. The M3 V8 on the otherhand is not suitable because it is an edgy, high strung engine that needs to be wound out to 8300 rpm to deliver its goods. You can quiet both engines down with an exhaust system appropriate for a luxury saloon, you cannot make an edgy 8300 rpm engine appropriate for an S-class.

[G. David Felt]

My point to the CTS-V being loud, is that the CTS-V engine can't be used in a flagship sedan. So Cadillac needs a V8 for performance, and a different V8 that is quiet. Just like the M3 V8 wouldn't work in a 7-series. So taking the CTS-V or ZR1 engine or slapping a turbo on the LS1 I don't see as a viable plan for a big luxury sedan.

To dfelt's point as to building what the customer wants, the S-class has been the best selling large luxury car in the world over the past 30 years, so it seems like that is what they want.

Actually, the CTS-V V8 is quite suitable for a flagship -- if it is fitted with the appropriate exhaust system that does not make a lot of noise. The LSA is a smooth and tractable engine with a 6100 rpm redline. The M3 V8 on the otherhand is not suitable because it is an edgy, high strung engine that needs to be wound out to 8300 rpm to deliver its goods. You can quiet both engines down with an exhaust system appropriate for a luxury saloon, you cannot make an edgy 8300 rpm engine appropriate for an S-class.

Correct, there are many noise canceling exhaust systems that would allow the CTS-V V8 to be in a world class ultra luxury sedan that would not only compete but beat the MB S class and BMW 7 or 8 class.

[smk4565]

Correct, there are many noise canceling exhaust systems that would allow the CTS-V V8 to be in a world class ultra luxury sedan that would not only compete but beat the MB S class and BMW 7 or 8 class.

The S-class is as quiet as the Volt at 70 mph and beats it at 50 mph. With either the diesel or the V8 it is 66 dba at 70 mph, and perhaps the next year's model beats that since Lexus and Rolls are lower. So they have the quiet the engine down a lot, then the S-class gets 25 mpg highway, the CTS-V gets 19 mpg, so they need to find another 6 mpg there. Not to mention the S-class is getting a 9-speed transmission next year so fuel economy will likely go up. And Cadillac does not have a V12 (or W12) like Audi, BMW and Mercedes have. It is hard to beat the S-class, Lexus has spend billions over 20 years and all they have is a car that even priced $30k cheaper sells half as many.

[G. David Felt]

Correct, there are many noise canceling exhaust systems that would allow the CTS-V V8 to be in a world class ultra luxury sedan that would not only compete but beat the MB S class and BMW 7 or 8 class.

The S-class is as quiet as the Volt at 70 mph and beats it at 50 mph. With either the diesel or the V8 it is 66 dba at 70 mph, and perhaps the next year's model beats that since Lexus and Rolls are lower. So they have the quiet the engine down a lot, then the S-class gets 25 mpg highway, the CTS-V gets 19 mpg, so they need to find another 6 mpg there. Not to mention the S-class is getting a 9-speed transmission next year so fuel economy will likely go up. And Cadillac does not have a V12 (or W12) like Audi, BMW and Mercedes have. It is hard to beat the S-class, Lexus has spend billions over 20 years and all they have is a car that even priced $30k cheaper sells half as many.

Cadillac has not yet optimized the use of quiet steel, insulation and blue printed a powerful V8 to meet the needs of a Ultra Luxury sedan. They can and eventually will do this I believe. In regards to gas mileage, there are many ways to optimize this also and we have not seen how the new V8 GM built or even the current CTS-V engine would perform with a 8 or 9 speed tranny. It is possible with the new V8 and supercharged or twin turbocharged even just normal but performance tuned, the V8 could do what is needed for the Ultra Luxury segment and with mid 20's to higher gas mileage.

In regards to V12, old school thinking and due to world wide changes, no longer a game changing need. Like the dinosaurs, the V12 will go away.

In it's place as Auto Makers learn how to build Performance high output electric motors, you will have an ubber quite High Compression generator that will be whisper quiet driving the vehicle to over 200mph while giving a cocoon world of peace and tranquility to the passengers.

[hyperv6]

V12's and 10's will all fade away accept from the highest end sports cars like a Enzo replacment.

Turbo V6 and V8 and TuRbo V8 engines will be more common in the low volume flagships of most makes.

What Cadillac has to do is make a car of the highest qulity in class. It needs to be as quiet as they can make in inside. Styling needs to set it appart not only from the other makes but also from the standard Cadillacs. Power needs to be more than it needs in the top option. Ride and handling needs to be the best it can be. Weight needs to be cut to give added perfromance and better handing. Technology also needs to be perfect and no goofy pain the ass things. It should be leading and usable.

Flagships are to make a statment and Cadillac needs to lead in all these areas.

The one thing this car needs to do is offer things to level the others don't and not share much of anything with other common models. Little as possible needs to be seen or noticed coming from any other lesser GM car.

[Drew Dowdell]

The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

Don't forget what top engine does the S class has.It is a twin turbo v12. So this supercharged v8 (if cadilac flagship will go against s class) must not be noisier (no supercharger whine in cabin) than the engine in the S class,Or at least is must not be heard in a cabin .Actually NVH should be on same level.

Even on the ZL-1 there is nearly zero supercharger whine... so I'm not sure what tree you think you're barking up here...

[Drew Dowdell]

My point to the CTS-V being loud, is that the CTS-V engine can't be used in a flagship sedan. So Cadillac needs a V8 for performance, and a different V8 that is quiet. Just like the M3 V8 wouldn't work in a 7-series. So taking the CTS-V or ZR1 engine or slapping a turbo on the LS1 I don't see as a viable plan for a big luxury sedan.

To dfelt's point as to building what the customer wants, the S-class has been the best selling large luxury car in the world over the past 30 years, so it seems like that is what they want.

The CTS-V engine could absolutely be used in a flagship. The "noise" is entirely from exhaust tuning.... The old F-body LT-1 powered Firebird was a lot louder than the LT-1 powered Fleetwood.

[Drew Dowdell]

Correct, there are many noise canceling exhaust systems that would allow the CTS-V V8 to be in a world class ultra luxury sedan that would not only compete but beat the MB S class and BMW 7 or 8 class.

The S-class is as quiet as the Volt at 70 mph and beats it at 50 mph. With either the diesel or the V8 it is 66 dba at 70 mph, and perhaps the next year's model beats that since Lexus and Rolls are lower. So they have the quiet the engine down a lot, then the S-class gets 25 mpg highway, the CTS-V gets 19 mpg, so they need to find another 6 mpg there. Not to mention the S-class is getting a 9-speed transmission next year so fuel economy will likely go up. And Cadillac does not have a V12 (or W12) like Audi, BMW and Mercedes have. It is hard to beat the S-class, Lexus has spend billions over 20 years and all they have is a car that even priced $30k cheaper sells half as many.

The S600 does NOT get 25mpg highway, it gets 12/19 and has a 50hp on the CTS-V. The only gasoline S-class to get 25mpg highway is the V6 Hybrid which is not a proper comparison to the CTS-V engine. The Cadillac XTS V6 already does 28mpg highway with more power than the S400 Hybrid and without any of the Hybrid stuff. So as far as engines are concerned, Cadillac seems to be more than safe.

I see you've taken your troll pills this morning.

[ZL-1]

Also more important question is will GM be able to show this premium v8 as genuine Cadillac engine and not something which is shared with cheaper cars and trucks.

[dado]

The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

Don't forget what top engine does the S class has.It is a twin turbo v12. So this supercharged v8 (if cadilac flagship will go against s class) must not be noisier (no supercharger whine in cabin) than the engine in the S class,Or at least is must not be heard in a cabin .Actually NVH should be on same level.

Even on the ZL-1 there is nearly zero supercharger whine... so I'm not sure what tree you think you're barking up here...

There is supercharger whine heard in cts-v. And that is a lsa engine. Nobody said it is loud. But you can hear it.

[Drew Dowdell]

The CTS-V and Top engine for the SLS will probably need to be a supercharged version of the LT engine pulling in 600~700 hp, probably retaining the 6.2 liter displacement for the cylinder wall thickness. Supercharging is easier than turbocharging from a packaging standpoint -- less intake piping and less exhaust plumbing. It will be less efficient, but in that price and performance bracket nobody is actually concerned about fuel costs and "green fashion" buyers would be shopping at Tesla anyway.

Don't forget what top engine does the S class has.It is a twin turbo v12. So this supercharged v8 (if cadilac flagship will go against s class) must not be noisier (no supercharger whine in cabin) than the engine in the S class,Or at least is must not be heard in a cabin .Actually NVH should be on same level.

Even on the ZL-1 there is nearly zero supercharger whine... so I'm not sure what tree you think you're barking up here...

There is supercharger whine heard in cts-v. And that is a lsa engine. Nobody said it is loud. But you can hear it.

Maybe I was enjoying it too much, but I hardly noticed it.

[hyperv6]

Why bother buying a LTS is you can get the same engine in the CTSV?

It needs something more or different.

The new Gen 5 engine with a SC or Twin Turbo'd to 750 HP would be nice. It also is do able since the present ZR1 engine has already been tested to 725 HP. The new engine should have no issues. The lower volume of this car will let them move the power up more too. It is not like they are going to sell a ton of these.

But the bottom line is you can not use the same engine in the LTS that could be had in any other model GM car. At the very least it needs it's own tune and it own look even if it just a Gen 5.

[Drew Dowdell]

Because the LTS is a completely different kind of car.... and you can get the AMG63 in C, E, and S sizes.... so if Benz can do it, why can't Cadillac?

[smk4565]

Correct, there are many noise canceling exhaust systems that would allow the CTS-V V8 to be in a world class ultra luxury sedan that would not only compete but beat the MB S class and BMW 7 or 8 class.

The S-class is as quiet as the Volt at 70 mph and beats it at 50 mph. With either the diesel or the V8 it is 66 dba at 70 mph, and perhaps the next year's model beats that since Lexus and Rolls are lower. So they have the quiet the engine down a lot, then the S-class gets 25 mpg highway, the CTS-V gets 19 mpg, so they need to find another 6 mpg there. Not to mention the S-class is getting a 9-speed transmission next year so fuel economy will likely go up. And Cadillac does not have a V12 (or W12) like Audi, BMW and Mercedes have. It is hard to beat the S-class, Lexus has spend billions over 20 years and all they have is a car that even priced $30k cheaper sells half as many.

The S600 does NOT get 25mpg highway, it gets 12/19 and has a 50hp on the CTS-V. The only gasoline S-class to get 25mpg highway is the V6 Hybrid which is not a proper comparison to the CTS-V engine. The Cadillac XTS V6 already does 28mpg highway with more power than the S400 Hybrid and without any of the Hybrid stuff. So as far as engines are concerned, Cadillac seems to be more than safe.

I see you've taken your troll pills this morning.

The S550 V8 with 429 hp and 516 lb-ft gets 25 mpg highway. The S63 AMG gets 15/23 mpg and has 563 hp and 664 lb-ft, so that is a better engine to compare to the CTS-V, except for the torque difference. I have no doubt that GM can crank a ton of horsepower from an engine, but can they do it efficiently and quietly. The Corvette gets good mileage because it is 3300 lbs, GM has to figure it out how to translate that to a 4500 lb sedan.

Plus a lot of this is irrelevant as the S-class is getting redone next year. The current car is entering it's 7th model year and it is still outselling much newer cars from BMW, Jaguar, and Audi. I hope Cadillac does enter this segment, but they have to do it right, and "old GM" thinking won't work. The XLR was supposed to challenge the Mercedes SL and the XLR bombed, they can't repeat those mistakes of cutting corners on powertrain, interior, etc.

[smk4565]

I think ultimate power is not the goal here anyway, the Lexus LS has sold well over the years (usually 2nd or 3rd in the class) and it never was a performance car. And the V12 BMW and Mercedes are selling in tiny numbers, in most cases you have to order it from the factory since they aren't even in dealer stock.

I think engine choice is key, the Cadillac flagship needs at least 4 engine options, diesel V6, turbo gas V6, gas V8 (maybe 2 levels of power) and a hybrid or plug-in green option. Mercedes already has a 40+ mpg S-class for Europe and China, and a plug-in S-class is coming, so they can market to the environmental crowd and the performance crowd.

[ZL-1]

Because the LTS is a completely different kind of car.... and you can get the AMG63 in C, E, and S sizes.... so if Benz can do it, why can't Cadillac?

I think it's basically because GM doesn't want to do it; there appears to be no long-term drive except to cater to the ATS/CTS/Escalade crowd... It's a management option to go the way they've gone at it for the last 10 years, but an option without any major opportunity for the Cadillac brand to really restablish itself as a world-class reference.

[dwightlooi]

There is supercharger whine heard in cts-v. And that is a lsa engine. Nobody said it is loud. But you can hear it.

Right and if you try really hard you can hear the turbocharger whistle in ANY turbocharged car. So, you point is?

There is a reason why the LSA (14/19 MPG -- Camaro ZL1) has notably worse fuel economy numbers compared to the LS3 (16/24 -- Camaro SS). I am citing Camaro numbers for a fairer and more accurate comparison since we are comparing engines not chassis weight and aerodynamics.

The reason is that like all supercharged systems, it consumes power to make additional power. Additional effort is made and fuel is burned to turn the supercharger connected to the crankshaft and force feed additional air into the cylinders. This means that superchargers are always less efficient than turbochargers which gets "free" energy from otherwise wasted exhaust heat and pressure. This means that in addition to burning more fuel because it is ingesting more air, the engine is also consuming additional fuel to ingest the additional air. Many supercharged engines have an electro-magnetic clutch which decouples the supercharger from the crank when it is not being called on to make extra power. This partly defrays the efficiency penalties. The 1987 Toyota MR2 (1st Gen) has one, the C230 Kompressor had one, the Audi 3.0T cars have one. The LSA does not so it suffers from the extra drag all the time.

There are a few reasons you do this. When the engine gets to a certain power level, you tend to forgo that clutch because it is a source of failure. When a high capacity supercharger is used, the engagement and disengagement tend to cause the clutch to fail (slip) over time unless it is sufficiently larger and robust. A sufficiently large and robust clutch may not fit. The other reason is that clutch tends to engage only with a reasonably deep throttle application and can cause smoothness issues with power delivery unless properly managed -- which get harder as the engine gets tremendously powerful. In the end, the compactness, reliability and lower cost of a directly driven supercharger won out over the increased fuel efficiency of a clutched supercharger.

The reduction in compression, drag from the supercharger and the lack of a decoupling clutch assembly amounted to a 2 mpg (city) / 5 mpg (hwy) difference in fuel economy in exchange for 154 additional horses and 136 lb-ft more twist. Could they have done better? Yes, perhaps 1 mpg / 2 mpg better if they adopted a clutch assembly, but 14/19 was deemed good enough for the LSA powered cars like the CTS-V or the ZL1 because their owners typically didn't care about that extra fuel economy and GM can do without the potential reliability issues and increased costs.

[hyperv6]

Because the LTS is a completely different kind of car.... and you can get the AMG63 in C, E, and S sizes.... so if Benz can do it, why can't Cadillac?

I think it's basically because GM doesn't want to do it; there appears to be no long-term drive except to cater to the ATS/CTS/Escalade crowd... It's a management option to go the way they've gone at it for the last 10 years, but an option without any major opportunity for the Cadillac brand to really restablish itself as a world-class reference.

The fact is till they get the ATS and CTS best in class why would anyone pony up big money on a LTS?

BMW was built pretty much from the 3 series up. They earned a rep on the lower priced cars and then expeanded it and moved the customers up that could afford it. Today Cadillac has the ATS almost there with only a need for some better engines. The new CTS also should prove to be class leading or right at that point. Once the public gets a good feel for these cars the LTS will be ready to be set upon the market.

People will risk $40K on an ATS to see how they like it but few will risk $70-100K on a LTS only to find it not of their liking. Please them with the ATS and CTS beyond the others in the market and they will be willing to take the plung on the LTS. The key though is it much not just be a expensive and more expensive Super Sport sedan.

[G. David Felt]

Because the LTS is a completely different kind of car.... and you can get the AMG63 in C, E, and S sizes.... so if Benz can do it, why can't Cadillac?

I think it's basically because GM doesn't want to do it; there appears to be no long-term drive except to cater to the ATS/CTS/Escalade crowd... It's a management option to go the way they've gone at it for the last 10 years, but an option without any major opportunity for the Cadillac brand to really restablish itself as a world-class reference.

The fact is till they get the ATS and CTS best in class why would anyone pony up big money on a LTS?

BMW was built pretty much from the 3 series up. They earned a rep on the lower priced cars and then expeanded it and moved the customers up that could afford it. Today Cadillac has the ATS almost there with only a need for some better engines. The new CTS also should prove to be class leading or right at that point. Once the public gets a good feel for these cars the LTS will be ready to be set upon the market.

People will risk $40K on an ATS to see how they like it but few will risk $70-100K on a LTS only to find it not of their liking. Please them with the ATS and CTS beyond the others in the market and they will be willing to take the plung on the LTS. The key though is it much not just be a expensive and more expensive Super Sport sedan.

I would agree with this, have GM spending money on building the worlds best ATS/CTS/SRX/Escalade in all versions. 4dr, 2dr, convertible, etc. In 3-5 years you can build an LTS.