GM's new 4.2L DOHC twin turbo V-8 !!

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peejay
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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by peejay » Sun Dec 02, 2018 2:38 pm

Brian P wrote:
Sun Dec 02, 2018 1:06 pm
Ford 2.7 Ecoboost.

https://www.caranddriver.com/features/l ... 2015-f-150
Interestingly, Ford has gone back to a setup like a separate cylinder block and crankcase with the 2.7.

Alternatively, they put the pan rail up against the bottom of the water jacket and use a very, very deep structural aluminum oil pan.

The 2.7 does make more torque/displacement than this 4.2l V8, and it is a truck engine so it is expected to run at heavy power all the time, unlike a passenger car engine. Corvettes don't weigh 6000lb and get expected to tow 16' enclosed trailers. (Or maybe they do as part of the C8 product development, I don't get the press releases :D )

The 3.5 Ecoboost is all-aluminum.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Brian P » Sun Dec 02, 2018 4:42 pm

Yeah, the 2.7 Ecoboost is a pretty interesting design. The structural load path is made of CGI and then it has a bolted-on external aluminum crankcase and oil pan (and the cylinder heads are aluminum). This is an engine in which the forced induction was designed in from day one. It may have parts that could loosely be described as "made of cast iron" but it is a thoroughly modern design with modern design features and construction methods.

I'm sure the external aluminum crankcase design was selected to minimize the amount of CGI that the engine is made of. The crankcase just needs to keep the oil inside and perhaps give someplace to attach the engine mounts.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Bazman » Sun Dec 02, 2018 5:10 pm

Great to see the GM release. I think the motor will be pretty epic for a mass production engine. I've owned 3 AMG 6.2's and can honestly say of all V8's I've ever owned, nothing topped them for all round reliability, usability, and power band. They'd pull from 1000rpm as well (or better) than any OHV that could rpm past 6.5k but these would flatten off and make the same power from 6500 to 7500rpm. Did over 200,000km on one and it was still running perfect.

It's laughable to bash all aluminum motors today. Yes - in an all out pump gas effort, there's 20+hp between a good alloy block and a good cast block... but that deficit can be reduced or near eliminated via careful reinforcing/redesign... and trust me, NASCAR run cast graphite blocks because they HAVE TO run iron. If they had the chance to take 60lb off the front of their cars they would or lose to those that did!

Only those that don't care about corners want cast iron in anything designed as a performance road car. I actively track and road race a twin turbo LS3 and have the turbos about mid-car (where the back seats used to be). For a front engine car it turns in pretty good. Thank you GM for the light 6.2...

Yessir - big hats off to GM for taking that weight off the front 20 years ago. That and decent heads were the greatest step forward in the Chev evolution IMO. Anyone says the LS platform is unreliable has rocks in their head. For everyone that had reliability issues (out of 5 million they're be some) there are hundreds and thousands that had none. A normal LS1 is so tight at 100,000 miles you can still add power adders and it'll be happy to take it and shift to 6500rpm daily (for a while).

The old SBC were iron, and their castings were complete crap in many cases, as were most Ford V8's, Mopar were better as they used more nickle - but still responded well to blue printing. The only reason the older motors lasted 200,000 miles was because they seldom saw over 5000rpm. Tolerances were all over the place... which was why you had good ones and bad ones, and why blueprinting the older Chev's was (is) a massive thing... all the old motors need blueprinting and better parts to make a decent performance engine. An LS is a decent performance motor (for street and weekend fun)
by anything from a simple tune to bolt ons, unless you want to get serious.

So.... relax guys that are worried - this GM engine will be a beauty IMO.

I am sad about the displacement drop - but they may have left some meat in there like they did with the LS - it went from 4.8 to 7.... though I doubt for emissions reasons they will ever make another 7L... leaving the aftermarket to do it, if feasible. Having said that I've experienced the new AMG twin turbo V8, and at only 4L it's friggin epic. Was ridiculous around a track for an OEM that could be daily driven.

These are good times - better than the old muscle car days

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by iadr » Sun Dec 02, 2018 9:09 pm

Bazman, I don't even know where to start-

200,000 km is half what we expect from a modern car here in Canada (and the US I'd assume). I don't know where you live, Holland maybe? But you just don't get the need in other parts of the world, for durability.

We who are critical, are not talking faults in an evolutionary design like the LS, but the complete crap like the "High Feature" 3.6L engine in GM SUV's.
Recently, I was tasked- I work in the service industry- with finding a good used replacement motor. Through all searches, the nearest one that was worth buying was 3,100km away. And even then, with 101,000km on it the dealer parts guy strongly recommended doing a "front end rebuild" (his words) with revised components, re-engineered after approx 1.5 million of these motors had been foisted on the customers.
Because of demand, the motors are worth more than the 5-6yo vehicles they are found in.

That is the GM we speak of- a company so badly managed as to lose market share year after year, take 11.2billion dollars net government funds, and produce vehicles with half the life expectancy they rightly should have.

Go on Bob is the oil guy and read the hundred+ post mortems of these V6 motors. Buy one yourself, and you will see our point. You and Newold are consumers. Armchair observers, honestly. Don't arrogate your expertise to think it on the level of those of us on this board who do service work for a living.
And yep, I worked for an MB dealer and have replaced 6.3 and 5.0 V8's for failures.

Currently, I work for Mazda, and if their 2.3 DI turbo from back in 2007 is what the industry is facing, I will be forced to leave said industry. Daily calls of failure. We'd rather the clients gave up and junked the CX7's.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Olds455 » Mon Dec 03, 2018 2:26 am

Truckedup wrote:
Sun Dec 02, 2018 1:01 pm
peejay wrote:
Sun Dec 02, 2018 12:31 pm
Truckedup wrote:
Sun Dec 02, 2018 11:55 am
Are the engine blocks of the latest PU truck Diesel engine cast iron or aluminum?
Neither. They use compacted graphite, which is technically "cast iron" in a broad sense, but is closer to steel or nodular iron in composition than the brittle cheeselike material that we think of as "cast iron".
Is this material used in any spark ignition engines?
You've never heard of CGI, called compacted graphite iron, engine blocks? Wow. That's crazy. Dart uses it to make blocks and so does GM in their DRCE engines for sure. Possibly more. CGI was patented at the same time as ductile iron back in 1949.
While ductile iron became a manufacturing staple, CGI never was seriously utilized despite possessing some very interesting properties. While not quite as strong as ductile iron, CGI is 75 percent stronger and up to 75 percent stiffer than gray iron.

The thermal and damping characteristics of CGI are midway between ductile and gray iron. It is five times more fatigue resistant than aluminum at elevated temperatures, and twice as resistant to metal fatigue as gray iron.

The nodularity and tensile strength of the material also increases as wall-section decreases.

These properties have most recently been found to make CGI ideally suited for engine manufacturing, where lighter and stronger materials are needed which can absorb more power.

An assembled automotive engine can be made nine percent lighter with CGI. The engine block weight alone can be reduced by 22 percent. This corresponds to a 15 percent reduction in length and a five percent reduction in height and width.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by exhaustgases » Mon Dec 03, 2018 2:44 am

iadr wrote:
Sun Dec 02, 2018 9:09 pm
Bazman, I don't even know where to start-

200,000 km is half what we expect from a modern car here in Canada (and the US I'd assume). I don't know where you live, Holland maybe? But you just don't get the need in other parts of the world, for durability.

We who are critical, are not talking faults in an evolutionary design like the LS, but the complete crap like the "High Feature" 3.6L engine in GM SUV's.
Recently, I was tasked- I work in the service industry- with finding a good used replacement motor. Through all searches, the nearest one that was worth buying was 3,100km away. And even then, with 101,000km on it the dealer parts guy strongly recommended doing a "front end rebuild" (his words) with revised components, re-engineered after approx 1.5 million of these motors had been foisted on the customers.
Because of demand, the motors are worth more than the 5-6yo vehicles they are found in.

That is the GM we speak of- a company so badly managed as to lose market share year after year, take 11.2billion dollars net government funds, and produce vehicles with half the life expectancy they rightly should have.

Go on Bob is the oil guy and read the hundred+ post mortems of these V6 motors. Buy one yourself, and you will see our point. You and Newold are consumers. Armchair observers, honestly. Don't arrogate your expertise to think it on the level of those of us on this board who do service work for a living.
And yep, I worked for an MB dealer and have replaced 6.3 and 5.0 V8's for failures.

Currently, I work for Mazda, and if their 2.3 DI turbo from back in 2007 is what the industry is facing, I will be forced to leave said industry. Daily calls of failure. We'd rather the clients gave up and junked the CX7's.
GM ? They got rid of their best divisions years ago, is that when the big down fall hit GM? EMD and Detroit Diesel the best of the best of GM, (Allison? I'm talking WW2 days) Euclid? . CGI ? Not needed in disposable engines, and Mercedes falls into that category as well.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Newold1 » Mon Dec 03, 2018 8:19 am

iadr wrote:
Sun Dec 02, 2018 9:09 pm
Bazman, I don't even know where to start-

200,000 km is half what we expect from a modern car here in Canada (and the US I'd assume). I don't know where you live, Holland maybe? But you just don't get the need in other parts of the world, for durability.

We who are critical, are not talking faults in an evolutionary design like the LS, but the complete crap like the "High Feature" 3.6L engine in GM SUV's.
Recently, I was tasked- I work in the service industry- with finding a good used replacement motor. Through all searches, the nearest one that was worth buying was 3,100km away. And even then, with 101,000km on it the dealer parts guy strongly recommended doing a "front end rebuild" (his words) with revised components, re-engineered after approx 1.5 million of these motors had been foisted on the customers.
Because of demand, the motors are worth more than the 5-6yo vehicles they are found in.

That is the GM we speak of- a company so badly managed as to lose market share year after year, take 11.2billion dollars net government funds, and produce vehicles with half the life expectancy they rightly should have.

Go on Bob is the oil guy and read the hundred+ post mortems of these V6 motors. Buy one yourself, and you will see our point. You and Newold are consumers. Armchair observers, honestly. Don't arrogate your expertise to think it on the level of those of us on this board who do service work for a living.
And yep, I worked for an MB dealer and have replaced 6.3 and 5.0 V8's for failures.

Currently, I work for Mazda, and if their 2.3 DI turbo from back in 2007 is what the industry is facing, I will be forced to leave said industry. Daily calls of failure. We'd rather the clients gave up and junked the CX7's.
The Older I Get, The Dumber I Get :wink:

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Newold1 » Mon Dec 03, 2018 8:42 am

ladr:
You need to get a grip dude! You work in such a narrow isolated service sector that you can't see the forest thru your rotten trees! You need to do some math and understand the meaning of percentages. As I stated, there are no perfect vehicles or perfect engines. The rediculous belief that engines in today's vehicles should all last 250,000 miles is not a valid argument. Consider that the far largest percentages of car purchasers today drive about 15K miles per year that would mean this massive percentage would be owning and driving it's cars over 15 years!! That will not and does not happen in the vast massive majority of owners! Study car time ownership numbers.
Your statements and judgements are so slanted because you work in a business where you try and find solutions for small percentage failures that when compared to the total quantities of production and use are in the single digits or lower ranges.
Your argument in my opinion is seriously flawed by the perception you have that engines must be perfect! Yet your very career and paycheck depends on the fact they are not and never will be!

As for me being an armchair observer, I can guaranty that I have wrenched on, repaired and built more engines than you clean hands have ever actually slaved over!
The Older I Get, The Dumber I Get :wink:

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Schurkey » Mon Dec 03, 2018 9:13 am

Brian P wrote:
Sun Dec 02, 2018 11:48 am
To my knowledge, Honda has NEVER built an engine with a cast iron block. Honda does have a reputation for building pretty good engines ...
1980 1500cc Civic CVCC had iron block, as did others in the CVCC model line before and after that time. I was jealous of the 1500cc Civics.

My 1980 1300cc Civic CVCC blew the #3 rod at 58K, knocked the front out of the aluminum block. Three beautiful rod bearings, five beautiful main bearings, and one rod in four pieces (the rod bolts were not broken) Happened at steady ~70 mph, Interstate, 5th gear.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Truckedup » Mon Dec 03, 2018 10:42 am

Schurkey wrote:
Mon Dec 03, 2018 9:13 am
Brian P wrote:
Sun Dec 02, 2018 11:48 am
To my knowledge, Honda has NEVER built an engine with a cast iron block. Honda does have a reputation for building pretty good engines ...
1980 1500cc Civic CVCC had iron block, as did others in the CVCC model line before and after that time. I was jealous of the 1500cc Civics.

My 1980 1300cc Civic CVCC blew the #3 rod at 58K, knocked the front out of the aluminum block. Three beautiful rod bearings, five beautiful main bearings, and one rod in four pieces (the rod bolts were not broken) Happened at steady ~70 mph, Interstate, 5th gear.
I've heard many stories of short engine life in early Civics...And the porous blocks? and oil consumption issues about 10-15 years ago.Same for Honda bikes,a few bad ones.. Every manufacturer makes mistakes, some more than others...What important is it's corrected early on with minimal cost to the consumer..
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Brian P » Mon Dec 03, 2018 2:23 pm

I didn't know about the iron-block Honda engines. It appears that it was a one and only situation, though, because everything they've built before and since has used aluminum.

I had a 1978 Honda Civic 1500 (Canadian market model) and that had an aluminum block. This would have been the ED engine. I had to change the water pump in that engine 5 times. (Obviously that's unrelated to it having an aluminum block ... just a crap accessory design.) Valve stem seals were an issue (again unrelated to block material). Carbon buildup was an issue (CVCC system). Carburetion in general was an issue (CVCC system ... and too many vacuum hoses).

Wikipedia (only source I can find) suggests that it was the 1600cc CVCC EF engine used in US market Accords 1976-1978 that had the iron-block engine. It doesn't say anything about the block material of other E-series engines. Canadian market models got the non-CVCC EG engine at the same time. Our family also had a 1983 Canadian-market Accord with a non-CVCC 1600 engine at that time (this was different from US models and different from the earlier 1600 engine) which would have been an EL engine, and I'm pretty sure that one had an aluminum block as well.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by peejay » Mon Dec 03, 2018 10:34 pm

iadr wrote:
Sun Dec 02, 2018 9:09 pm
Bazman, I don't even know where to start-

200,000 km is half what we expect from a modern car here in Canada (and the US I'd assume). I don't know where you live, Holland maybe? But you just don't get the need in other parts of the world, for durability.

We who are critical, are not talking faults in an evolutionary design like the LS, but the complete crap like the "High Feature" 3.6L engine in GM SUV's.
Recently, I was tasked- I work in the service industry- with finding a good used replacement motor. Through all searches, the nearest one that was worth buying was 3,100km away. And even then, with 101,000km on it the dealer parts guy strongly recommended doing a "front end rebuild" (his words) with revised components, re-engineered after approx 1.5 million of these motors had been foisted on the customers.
Because of demand, the motors are worth more than the 5-6yo vehicles they are found in.

That is the GM we speak of- a company so badly managed as to lose market share year after year, take 11.2billion dollars net government funds, and produce vehicles with half the life expectancy they rightly should have.

Go on Bob is the oil guy and read the hundred+ post mortems of these V6 motors. Buy one yourself, and you will see our point. You and Newold are consumers. Armchair observers, honestly. Don't arrogate your expertise to think it on the level of those of us on this board who do service work for a living.
And yep, I worked for an MB dealer and have replaced 6.3 and 5.0 V8's for failures.

Currently, I work for Mazda, and if their 2.3 DI turbo from back in 2007 is what the industry is facing, I will be forced to leave said industry. Daily calls of failure. We'd rather the clients gave up and junked the CX7's.
The Bob Is The Oil Guy forum is full of frickin' morons who think stupid things like "oil doesn't wear out" and don't change their oil until an oil analysis tells them that the oil is used up. Of course people on their forum will have a lot of problems.

In the real world, that has people who aren't complete idiot spendthrifts, if you have a High Feature and change the oil every 3-5000mi, they last a good long time. I have a few in my care that are well, well beyond 200k km on the chainsets that GM installed on the assembly line. The common link with them all is REGULAR OIL CHANGES with GOOD OIL, period. None of this 15-20k mile ridiculousness.

The biggest problem I see with the High Feature engine is people who believe the "Oil Life Monitor" and drive the car until the monitor reaches zero, or the oil pressure light comes on because the engine is five quarts low in a six quart system, which ever comes first. If you actually maintain the cars, instead of training them to run low on oil that is half contaminants because the oil life monitor says it isn't due yet, then the engines have no problem at all.

The "oil life monitor" system is mostly a way to make people who lease a vehicle feel good about low maintenance costs. What do they care, they will be turning it in after 3 years, after that it's someone else's problem. Almost as bad as the apparent German attitude of, don't maintain a car, you should replace it with a new car instead because new cars are more efficient than the two year old junk you are driving.

The DISI engine is a typical Mazda somewhat-underengineered problem child, and I say this as someone with a long history with Mazda. (Currently own two RX-7s and a twin distributor RX-3, have had three other RX-7s, always at least one in my life since 1998) The biggest issue with the DISI is that Mazda tuned the engine to the knife edge of what the high pressure fuel pump could keep up with when everything is new and in perfect working order. After some entropy happens in the HPFP, you find yourself getting some rod-shattering detonation at low RPM because the tiny little turbo can spool up faster than the fueling can keep up. Notice that Ford, who uses the sam architecture but Bosch direct-injection components and less specific output, has no problems from their 2.0 Ecoboosts.

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by Bazman » Tue Dec 04, 2018 12:36 am

Most of the 6.3 AMG motors that got replaced were due to the known head bolt problem from 07-11... again - a small % of them. I had 2 from that era - never a problem nor did I ever meet anyone that did. Of course there are stories all over the internet.... but the 99% with no problems have no reason to post or took advantage of the factory warranty head bolt upgrade.

My last one was a late 13 and it laid down 432rwhp stock, 485rwhp with headers and a custom tune on pump gas. It could also get mid 20's mpg easily highway. On road courses it took more than a chipped GTR with big bore or a Gallardo 560-4 to pull away from me at any speed and in any gear (I had good tires lol). Those hand built motors are the stuff of hall of fame. Mine saw 9300rpm due to a missed shift, never missed a beat and car still runs as strong now as back then in 14. Anyone bags the 6.3 is not being accurate

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by digger » Tue Dec 04, 2018 4:39 am

Bazman wrote:
Tue Dec 04, 2018 12:36 am
Most of the 6.3 AMG motors that got replaced were due to the known head bolt problem from 07-11... again - a small % of them. I had 2 from that era - never a problem nor did I ever meet anyone that did. Of course there are stories all over the internet.... but the 99% with no problems have no reason to post or took advantage of the factory warranty head bolt upgrade.

My last one was a late 13 and it laid down 432rwhp stock, 485rwhp with headers and a custom tune on pump gas. It could also get mid 20's mpg easily highway. On road courses it took more than a chipped GTR with big bore or a Gallardo 560-4 to pull away from me at any speed and in any gear (I had good tires lol). Those hand built motors are the stuff of hall of fame. Mine saw 9300rpm due to a missed shift, never missed a beat and car still runs as strong now as back then in 14. Anyone bags the 6.3 is not being accurate
Mercedes-AMG couldn't even calculate the displacement correctly

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Re: GM's new 4.2L DOHC twin turbo V-8 !!

Post by peejay » Tue Dec 04, 2018 7:14 am

digger wrote:
Tue Dec 04, 2018 4:39 am
Bazman wrote:
Tue Dec 04, 2018 12:36 am
Most of the 6.3 AMG motors that got replaced were due to the known head bolt problem from 07-11... again - a small % of them. I had 2 from that era - never a problem nor did I ever meet anyone that did. Of course there are stories all over the internet.... but the 99% with no problems have no reason to post or took advantage of the factory warranty head bolt upgrade.

My last one was a late 13 and it laid down 432rwhp stock, 485rwhp with headers and a custom tune on pump gas. It could also get mid 20's mpg easily highway. On road courses it took more than a chipped GTR with big bore or a Gallardo 560-4 to pull away from me at any speed and in any gear (I had good tires lol). Those hand built motors are the stuff of hall of fame. Mine saw 9300rpm due to a missed shift, never missed a beat and car still runs as strong now as back then in 14. Anyone bags the 6.3 is not being accurate
Mercedes-AMG couldn't even calculate the displacement correctly
There's a twin turbo 4 liter (?) that they are sticking 63 suffixes on. This is not the same as the actual 6.3 that Mercedes discovered why socket-head bolts need to have tall heads.

Kind of like how BMW adds a whole lot to the number for turbo engines. That newer 330 or 530 really has a turbo two-liter in it, but the older 330s and 530s had 3 liter sixes. Or 3 liter V8s, depending on year.

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