CT5-V and CT4-V BLACKWING -- Return to Big Power

[dwightlooi]

With the new CT4-V and CT5-V, Cadillac has returned to big power:-

• CT4-V Blackwing gets 474 bhp / 445 lb-ft Twin-Turbo V6 (LF4)
• CT5-V Blackwing gets 668 bhp / 659 lb-ft Supercharged Pushrod V8 (LT4)

This is definitely welcomed news for Cadillac V-Car fans who were completely underwhelmed by last year's CT4-V and CT5-V that boasted a whopping 10~25 hp gain over ordinary CT5 cars and base model Silverado pickups. The return to Pushrod power is encouraging, showing that GM is finally playing to it's architectural strength rather than chasing after other manufacturer's design weaknesses.

Still, it begs the question as to why Cadillac (or GM in general) decided to downgraded the 3.0TT (LGY) engine for the CT5 from 404 bhp to 335 bhp (360 bhp in the CT5-"V*") which saved no money, gained no compression, gained no torque and gained no mpg over the same engine in the CT6 (LGW). It also represents a missed opportunity to evolve the promising 2.7T engine. The 2.7T -- as I have previously articulated -- could easily have made 420 bhp @ ~5300 rpm / 420 lb-ft @ ~2800 rpm with about 20~22 psi of boost from properly sized turbocharger like a G25-550D while providing markedly better drivability than any AMG 2.0T engine of similar output by virtue of its 36.5% greater displacement. It would have been a fitting powerplant for the CT4-V Blackwing and it would have captured the 4-cylinder performance crown for GM.

This also confirms the abandonment of the hot-Vee 4.2L twin turbo DOHC V8 (LTA) used in the short lived CT6-V and which GM had declined to employ in the new Escalade, CT5-V Blackwing or any other suitable vehicle -- a total waste of R&D and tooling dollars.

https://www.cadillac.com/future-vehicles/blackwing-reservation

https://www.youtube.com/watch?v=dg_hh8A78kM

 

[David]

Happy to see the new V's, good for Cadillac to embrace this and also continue to offer 6 speed manual transmissions in the auto's on top of the 10 speed auto's.

While many were excited by the TT 4.2L DOHC V8. I stand by my past comments that DOHC engines do not really gain you much of anything except complexity, weight, High Horsepower with little Torque and a high pitch annoying sound. Glad to see the push rod V8 Supercharged is back!

[dwightlooi]

The "fake" V CT5 and CT4, as well as the abandonment of the CT6 got me from the CTS VSport into an Audi A8L 4.0T in Dec 2019. That and the absolutely dismal value retention of Audi flagship Sedans in this age of SUV stupor. It came down to a 4 year old A8L 4.0T with the flagship B&O audio system for $31.6K or a 3.5 year CT6 3.0T Platinum for 35K which didn't even have the rare Panaray system. Both cars had 32~37K mileage on the clock. It was no contest.

[dwightlooi]

9 hours ago, David said:

While many were excited by the TT 4.2L DOHC V8. I stand by my past comments that DOHC engines do not really gain you much of anything except complexity, weight, High Horsepower with little Torque and a high pitch annoying sound. Glad to see the push rod V8 Supercharged is back!

Actually, they NEVER got any more horsepower than their contemporary pushrod engines of the same mass or external dimensions. This is because they are as big, and weigh as much as, a push rod engine of ~50% greater displacement. They achieve simply achieve the same power output using less displacement, less torque and the ability to maintain higher torque outputs above 6000 rpm. While lower displacement gives them a theoretical edge in fuel economy by operating at a larger throttle opening for any given torque demand, this does not usually pan out in real life because twice as many valves and four times as many cams also incur higher frictional losses. At the same time, lower torque means that their powerband is less accessible in daily driving. To combat this, many resort to low pressure turbocharging to bolster the torque output and bring it lower into the rev range. This incurs additional efficiency losses from back pressure due to the turbine(s) and reduced static compression.

Case and point:

Audi 4.0T 32-valve Hot-Vee bi-turbo DI V8 (CEU)

• Engine Mass: 219 kg
• 435 hp @ 5100 rpm
• 445 lb-ft @ 1,500~4,500 rpm
• 18 mpg (City) / 28 mpg (Hwy) (RS6)
• Crate Engine Price: $30,800

GM 6.2 16-valve Pushrod DI V8 (LT1)

• Engine Mass: 211 kg
• 455 hp @ 6,000 rpm
• 460 lb-ft @ 4,600 rpm
• 16 mpg (City) / 27 mph (Hwy) (SS)
• Crate Engine Price: $8,400

[Drew Dowdell]

On 2/2/2021 at 3:46 PM, dwightlooi said:

The "fake" V CT5 and CT4, as well as the abandonment of the CT6 got me from the CTS VSport into an Audi A8L 4.0T in Dec 2019. That and the absolutely dismal value retention of Audi flagship Sedans in this age of SUV stupor. It came down to a 4 year old A8L 4.0T with the flagship B&O audio system for $31.6K or a 3.5 year CT6 3.0T Platinum for 35K which didn't even have the rare Panaray system. Both cars had 32~37K mileage on the clock. It was no contest.

That sounds like a sweet deal on the A8L!

[ykX]

17 minutes ago, Drew Dowdell said:

That sounds like a sweet deal on the A8L!

Until he needs to repair something on it, which he will.

[Drew Dowdell]

4 minutes ago, ykX said:

Until he needs to repair something on it, which he will.

He doesn't seem to keep his cars long enough to require major repairs... and with that mileage, it maybe was a CPO.

[ccap41]

On 2/2/2021 at 1:54 PM, dwightlooi said:

The 2.7T -- as I have previously articulated -- could easily have made 420 bhp @ ~5300 rpm / 420 lb-ft @ ~2800 rpm with about 20~22 psi of boost from properly sized turbocharger like a G25-550D while providing markedly better drivability than any AMG 2.0T engine of similar output by virtue of its 36.5% greater displacement.

That sounds like a recipe for lots of lag. 

Also, it's a truck engine and most reviews speak of how unrefined and lack of smoothness it has for a Cadillac. 

[dwightlooi]

21 minutes ago, Drew Dowdell said:

That sounds like a sweet deal on the A8L!

70.7% depreciation over four years... that's why you should never buy them new!

The car stickered for $108K new in 2015. By Dec 2019, it's worth $31.6K with 36K miles on the clock. And, that is Certified Pre-Owned with an additional year of Audi Warranty, no accidents and no major blemishes. It's the first year of the facelifted D4 A8 (2015-2017 of 2011-2017) with the revised LED lights, trunk contour and MMI. Comes with active air suspension, massage seats and the "rising mushroom" B&O audio system. The 4.0T (CEU) engine makes 435 bhp @ 5100 rpm with 445 lb-ft @ 1500 rpm (up 15 hp from the 2013~2014 cars; 2011~2012 had 367hp NA 4.2L V8). You can bump that to ~ 500hp / 550 lb-ft if you don't care about the 70K extended warranty with a software flash. Window sticker lists 18 / 28 mpg, although I find that about 15 / 23 is more typical in real world driving.

[dwightlooi]

1 hour ago, ccap41 said:

That sounds like a recipe for lots of lag. 

Also, it's a truck engine and most reviews speak of how unrefined and lack of smoothness it has for a Cadillac. 

Not really... should be about the same as the 472hp 3.6TT V6 (LF4) and definitely less than the 382hp CLA45 2.0T (M139). V6 bi-turbos have a built-in inefficiency with regards to turbocharger responsiveness. This stems from the fact that the exhaust pulses from each bank of three cylinders are "interrupted" and there are significant gaps where the turbine receives no driving force from the engine (see illustrations below). A 150 hp/liter 4-potter is not too similar in responsiveness to a 132 hp/liter 3-cylinder engine -- all else being equal.

Edited February 5, 2021 by dwightlooi

[dwightlooi]

1 hour ago, ykX said:

Until he needs to repair something on it, which he will.

LOL... we'll see. A fair bit of warning for anyone looking at the Audi A8, S8, S7 or RS6 with 4.0T engine. It comes with a bonafide example of totally retarded German engineering!

The two turbos in the Vee of the engine is fed by an oil line with an inline strainer. This strainer is beneath the turbos, intake plumbing and air-water intercooler. It is supposed to keep the oil supply to the turbochargers "cleaner" and extend their lives. The problem is that a "strainer" is by definition a filtration device which traps gunk. Like a filter that never gets replaced, it'll eventually clog and cut off all oil flow to the turbos causing them to grenade! At best, this destroys the turbos. At worst, the fragments get past the intercooler into the cylinders scoring the walls and junks the whole engine. A new engine from Audi is $30K not including labor to install it putting the car beyond economical repair.

The strainer is NOT listed as a service item and according to maintenance schedules you never replace it. But if you don't, it is a question of when not if your engine blows up. 4.0Ts have been blowing with as low as 40,000 miles.

If you do replace it, it's a 10 hour job ($2850 labor @ $285/hr at the dealership) that requires the removal of the front bumper, radiator, front support beam, intercooler and intake plumbing. The strainer itself is a $28 part and many owners simply remove it (although you'll need to find an independent shop to do that as the dealer will NOT do it without reinstalling a new filter).

The turbochargers are covered by a 10-yr / 70,000 mile extended emissions warranty so I am going to run them up to 70K then pay an independent shop to service the strainer (or just remove it). Good thing about the A8 (vs the RS6 or S7) is that it is designed for the W12 engine and there is enough room to remove the IC without removing the front bumper, radiator or support beam. This cuts the job down to ~6 hours or approximately $1000 at $165 / hr (California labor rate) at a reputable independent shop familiar with these Audi engines.

Only the Germans are capable of designing an engine with a filter that costs thousands or dollars and 10 hours to get to which "protects" your engine by causing it totally destroy itself!

Edited February 5, 2021 by dwightlooi

[ykX]

@dwightlooi

Exactly.  There is a good reason why very expensive German sedans loose over 60-70% of their value after 3-4 years.  They are great when you are leasing them and that's about it.  You have CPO and probably will replace it before the warranty expires, but I wouldn't come close to those cars no matter how good the deal is.

[dwightlooi]

23 minutes ago, ykX said:

@dwightlooi

Exactly.  There is a good reason why very expensive German sedans loose over 60-70% of their value after 3-4 years.  They are great when you are leasing them and that's about it.  You have CPO and probably will replace it before the warranty expires, but I wouldn't come close to those cars no matter how good the deal is.

I am fine with spending a thousand dollars to deal with a known issue when I get $76,000 off on the car!

[surreal1272]

Personally, I like not having to take my car for expensive repair after expensive repair, regardless of how much I paid for the car but hey, I guess some folks have time to deal with that non-sense. 

[David]

1 hour ago, dwightlooi said:

I am fine with spending a thousand dollars to deal with a known issue when I get $76,000 off on the car!

I can respect that, but as you said, a $28 dollar part with a $1,000 labor bill. That right there is a deal breaker for me, would rather support an American company with much cheaper parts and usually able to do the work myself or still way cheaper labor for Cadillac over Audi.

I respect your choice and agree with the huge discount that is a great deal, but my GM V8's have proven to be far more durable than dealing with a ticking Grenade of German engineering design.

Take a Pushrod V8 over over rev'd DOHC German V8 any day.

I find it interesting that we do not find German V8's with 200,000 to 300,000 miles on the road unlike Ford and GM trucks, SUVs and cars. It makes me question that superior German engineering attitude.

[dwightlooi]

39 minutes ago, David said:

I can respect that, but as you said, a $28 dollar part with a $1,000 labor bill. That right there is a deal breaker for me, would rather support an American company with much cheaper parts and usually able to do the work myself or still way cheaper labor for Cadillac over Audi.

I respect your choice and agree with the huge discount that is a great deal, but my GM V8's have proven to be far more durable than dealing with a ticking Grenade of German engineering design.

Take a Pushrod V8 over over rev'd DOHC German V8 any day.

I find it interesting that we do not find German V8's with 200,000 to 300,000 miles on the road unlike Ford and GM trucks, SUVs and cars. It makes me question that superior German engineering attitude.

LOL... I would too. But there was no CT6 with an LT1, LT2 or LT4. Heck the ATS-V didn't have the Pushrod V8 either. The CT6-V was new then and I don't buy new cars. The CTS-V held their values surprisingly well and was $60K -- almost twice as much as the Audi A8 and I already had the CTS Vsport which apart from the engine is the same car. The same can be said of the "fullsize" M or AMG cars.

It came down to the CT6 3.0TT, the 740, GS F, Genesis 5.0 and the A8L 4.0TT.

BTW, the 4.0T is anything but over revved. As a matter of fact, it is so under revved one ponders why it bothers with a 4-valve head at all! The engine's rev limit is 6000 rpm. Its 435hp peak power is delivered at 5100 rpm. The two tiny turbos deliver a peak of 12 psi of boost tappering off to 8 psi at the upper reaches to produce a very mild 445 lb-ft from 4.0 liters. Which begs the question... why all the complexity with 4 cams, variable vale timing, variable valve lift, twin turbos, air-to-water intercooler, direct injection, etc. to make... well... the same power as a port injected LS3 V8? And do so with less reliability, way more money and more weight???

Edited February 5, 2021 by dwightlooi

[David]

20 minutes ago, dwightlooi said:

LOL... I would too. But there was no CT6 with an LT1, LT2 or LT4. Heck the ATS-V didn't have the Pushrod V8 either. The CT6-V was new then and I don't buy new cars. The CTS-V held their values surprisingly well and was $60K -- almost twice as much as the Audi A8 and I already had the CTS Vsport which apart from the engine is the same car. The same can be said of the "fullsize" M or AMG cars.

It came down to the CT6 3.0TT, the 740, GS F, Genesis 5.0 and the A8L 4.0TT.

BTW, the 4.0T is anything but over revved. As a matter of fact, it is so under revved one ponders why it bothers with a 4-valve head at all! The engine's rev limit is 6000 rpm. Its 435hp peak power is delivered at 5100 rpm. The two tiny turbos deliver a peak of 12 psi of boost tappering off to 8 psi at the upper reaches to produce a very mild 445 lb-ft from 4.0 liters. Which begs the question... why all the complexity with 4 cams, variable vale timing, variable valve lift, twin turbos, air-to-water intercooler, direct injection, etc. to make... well... the same power as a port injected LS3 V8? And do so with less reliability, way more money and more weight???

Awesome info Dwight, and Yes, TOTALLY AGREE with you on the questions you ask about the German V8. I did not know that it did not rev like the other german V8's which does beg the question why?

[dwightlooi]

53 minutes ago, David said:

Awesome info Dwight, and Yes, TOTALLY AGREE with you on the questions you ask about the German V8. I did not know that it did not rev like the other german V8's which does beg the question why?

This question is best answered chronologically...

(1) They went to DOHC 4-valves to produce screamer engines like the BMW (E90) M3's S65 4.0L V8 (414 hp @ 8,300 rpm, 290 lb-ft @ 3,900 rpm, 8,400 rpm rev limit) and the Audi (B7) RS4's 4.2L V8 (414 hp @ 7,800 rpm, 317 lb-ft @ 5,500 rpm, 8,250 rpm rev limit)

(2) They found that these engines kinda sucked in daily driving and had horrible fuel economy (14/20 mpg for the M3 or 14/21 mpg for the RS4 vs 16/25 for the 6.2L Camaro SS of the same period). Why? Because these 8000+ rpm engines had massive amounts of valve lift and overlap, which is tamed by variable cam phasers that open the exhaust way early and closes the intake really late to dial out the overlap at lower rpms. While this made the engines civil and smooth (if lethargic) for daily driving, venting the exhaust early wastes a good amount of energy from the combustion while driving up hydrocarbon emissions, while closing the intake really late costs you effective compression and reduces realized displacement.

(3) When stricter emissions and fuel economy targets came around, the Germans abandoned the screamers and went to turbocharging, but they kept their complex valve train designs -- 4-valve heads, multiple overhead camshafts and advanced valve timing implements. This makes for much more drivable engines, better emissions and better fuel economy, but also complex and expensive engines that no longer utilize the airflow advantages their complex valve train theoretically affords. Of course they cannot resist throwing in deeply buried fuel strainers that clogs up oil flow and grenades engines!

(4) Engines like the 4.0T (CEU) do not rev high because the tiny turbos that gave 1500 rpm torque peaks also run out of breathe at 5100 rpm and there is nothing "up there". They were given a low red line because the cars will be slower if they revved to 7000 or 8000 rpm instead of shifting at 5,900 rpm.

Edited February 5, 2021 by dwightlooi

[Guest Vcaddyman]

On 2/5/2021 at 3:17 PM, dwightlooi said:

This question is best answered chronologically...

(1) They went to DOHC 4-valves to produce screamer engines like the BMW (E90) M3's S65 4.0L V8 (414 hp @ 8,300 rpm, 290 lb-ft @ 3,900 rpm, 8,400 rpm rev limit) and the Audi (B7) RS4's 4.2L V8 (414 hp @ 7,800 rpm, 317 lb-ft @ 5,500 rpm, 8,250 rpm rev limit)

(2) They found that these engines kinda sucked in daily driving and had horrible fuel economy (14/20 mpg for the M3 or 14/21 mpg for the RS4 vs 16/25 for the 6.2L Camaro SS of the same period). Why? Because these 8000+ rpm engines had massive amounts of valve lift and overlap, which is tamed by variable cam phasers that open the exhaust way early and closes the intake really late to dial out the overlap at lower rpms. While this made the engines civil and smooth (if lethargic) for daily driving, venting the exhaust early wastes a good amount of energy from the combustion while driving up hydrocarbon emissions, while closing the intake really late costs you effective compression and reduces realized displacement.

(3) When stricter emissions and fuel economy targets came around, the Germans abandoned the screamers and went to turbocharging, but they kept their complex valve train designs -- 4-valve heads, multiple overhead camshafts and advanced valve timing implements. This makes for much more drivable engines, better emissions and better fuel economy, but also complex and expensive engines that no longer utilize the airflow advantages their complex valve train theoretically affords. Of course they cannot resist throwing in deeply buried fuel strainers that clogs up oil flow and grenades engines!

(4) Engines like the 4.0T (CEU) do not rev high because the tiny turbos that gave 1500 rpm torque peaks also run out of breathe at 5100 rpm and there is nothing "up there". They were given a low red line because the cars will be slower if they revved to 7000 or 8000 rpm instead of shifting at 5,900 rpm.

On 2/2/2021 at 12:01 PM, David said:

Happy to see the new V's, good for Cadillac to embrace this and also continue to offer 6 speed manual transmissions in the auto's on top of the 10 speed auto's.

While many were excited by the TT 4.2L DOHC V8. I stand by my past comments that DOHC engines do not really gain you much of anything except complexity, weight, High Horsepower with little Torque and a high pitch annoying sound. Glad to see the push rod V8 Supercharged is back!