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Will GM’s New 2.7-Liter Turbo Gas Engine Pull Stronger Than Its 2.8-Liter Duramax Diesel?

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Colossus Senior Enthusiast

Colossus

Posted
Posted

Sadly I fear we'll eventually reach a point where there will no longer be V8s in trucks, but rather turbocharged 4s and 6s.  And there will be nothing we can do about it.  Other than not buying them. 

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Daly
Daly

The 2.7 looks like it'll be a nice little engine. Doubtful I'll ever own one in a full-size, call me old school (I'll gladly take that moniker by the way), but full-size trucks should have v8's IMO. B

newdude
newdude

The big difference is the HP.  That 2.7 Turbo gas makes near double the HP of the 2.8 Duramax.  The 2.8 is a sweetheart of a powerplant, but as you break 3000rpm, she starts to steam off due to the to

Epsilon Plus
Epsilon Plus

The 2.7 should be in future ZR2s. The diesel and it's sub 200hp and meh torque has been a disappointment from the beginning.

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Colossus Senior Enthusiast

Colossus

Posted
Posted

When it comes to trucks and towing and working, torque is more important than HP.  High HP numbers are great for racing and sports cars, but torque is what gets the job done. 

Colossus Senior Enthusiast

Colossus

Posted
Posted

As hard as it is, I have decided to not put down the little turbo 4 until I get the chance to test drive it to decide for myself. 

DONWT15 Enthusiast

DONWT15

Posted
Posted
8 hours ago, Colossus said:

As hard as it is, I have decided to not put down the little turbo 4 until I get the chance to test drive it to decide for myself. 

:thumbs:

hizzo3 Enthusiast

hizzo3

Posted
Posted
Cite all the data you want, there is no replacement for displacement... Turbo charged v6's in trucks don't seem like a good recipe for long term durability...
I will argue that point wholely.
1) how does NA vs Turbo handle atmosphere?
NA) by losing 3% every 1,000 ft
Turbo) keeps same Max HP. Turbos spin faster in the less dense air keeping the intake pressure at the same level. This is the same concept used in turbo-prop/turbofans used in planes and helicopters.

2) how does NA vs Turbo handle changing engine loads
NA) it can only create negative pressure in the manifold for lower demands. The displacement stays the same, AFM ignored (which is why GM uses it, but parasitic losses)
Turbo) by using a smaller engine and a compressor, most the time the engine manifold pressure is positive. By increasing pressure, a smaller engine can actually move MORE air than an NA engine 2x it's size. More air + more fuel = more power

So why all this talk of turbo now when the small block V8 has been king? Well simple... Computers. Better modeling, better programming, better engine computers, better understanding of the physics.

Did you know that the first year of F1 moving to the newest set of turbos, tire manufacturers had problems? Yeah, coming out of the turns, the turbos spooled via an electric motor essentially acting as a procharger (on intake and exhaust mind you). The stresses were too much and teams had to dial down the new systems to avoid killing off their tires.





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Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

Since HP is simply a mathematical number based on torque and rpm it would make complete sense that the HP is higher when the torque is also higher at a set rpm. With the torque line the way it is, who cares about the hp number. 

 

This gas engine is undersquare.  Been a long time since we had an undersquare gas engine in a car or truck.  That explains the low redline.  Running what I think is going to be the first "living" camshaft gives the high flat torque line.  Can't really call it a torque curve now.  By essentially giving the engine a unique camshaft profile for each and every rpm is something that has been dreamt about. If they can control lift and duration, as well as cam timing, you can have optimal valve action instantly.  If this engine gives a good life, I can see it removing the 5.3 from the lineup.  A pickup running tp 60mph in under 7 seconds, doubt a 6.2 can do that now, and for sure a 5.3 can't. 

Wonder if they will come up with an undersquare inline 6 with the same camshaft technology and make that an optional engine? 

Dixon700 Enthusiast

Dixon700

Posted
Posted
On 5/22/2018 at 6:39 PM, Daly said:

but full-size trucks should have v8's IMO.

I'll just leave this here......

Hardest working pickup engine out there.

 

67l_cummins_turbo_diesel_engine-300x300.jpg

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted
24 minutes ago, Dixon700 said:

I'll just leave this here......

Hardest working pickup engine out there.

 

67l_cummins_turbo_diesel_engine-300x300.jpg

Some think that since trucks have come with v8s since the 30s that it must be the best engine.  As long as GM has done the proper real life stress testing on this new engine it may very well be a major advancement.  They aren't revving the snot out of it, it may surprise a lot of skeptics. 

hizzo3 Enthusiast

hizzo3

Posted
Posted

And to my point earlier... NA V8's suck in the mountains. That is when you need the most power anyway. A force fed engine is much better.

 

Also, everyone knows that they do make NA diesels, right... They are even worse than NA gas engines on paper, but cheaper to manufacture.

 

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Daly Senior Enthusiast

Daly

Posted
Posted (edited)
1 hour ago, Dixon700 said:

I'll just leave this here......

Hardest working pickup engine out there.

 

67l_cummins_turbo_diesel_engine-300x300.jpg

I'm not talking about diesel's, but nice try. I'll gladly take the 3.0 duramax in the 1500. But in gas form, IMO, it's a V8. 

Edited by Daly
hizzo3 Enthusiast

hizzo3

Posted
Posted

Please, someone get the I4, tune it and to an axle pull with a V8 so we can put this to rest.

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Daly Senior Enthusiast

Daly

Posted
Posted

And to prove what? That a modified 4 Cyl can be as good as a stock V8?

 

 

michigan2500hd Senior Enthusiast

michigan2500hd

Posted
Posted
The 2.7 EB will humiliate and small block and any LT.  The 3.5 EB crushes the LT 6.2.  The new GM GTDI 2.7 will sell like crazy, and should have an excellent tow rating.  It will also outshine any V8, especially when it comes to passing a gas station.
I don't see how the egoboost crushes the 6.2. I've never had one able to hang with me yet. As for the 2.7 it's just downright silly when they line up and think they have something cool. One of my favorite things to do is dust the blue kool-aid drinking crowd who listens to Fords oral crap.

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michigan2500hd Senior Enthusiast

michigan2500hd

Posted
Posted
Since HP is simply a mathematical number based on torque and rpm it would make complete sense that the HP is higher when the torque is also higher at a set rpm. With the torque line the way it is, who cares about the hp number. 
 
This gas engine is undersquare.  Been a long time since we had an undersquare gas engine in a car or truck.  That explains the low redline.  Running what I think is going to be the first "living" camshaft gives the high flat torque line.  Can't really call it a torque curve now.  By essentially giving the engine a unique camshaft profile for each and every rpm is something that has been dreamt about. If they can control lift and duration, as well as cam timing, you can have optimal valve action instantly.  If this engine gives a good life, I can see it removing the 5.3 from the lineup.  A pickup running tp 60mph in under 7 seconds, doubt a 6.2 can do that now, and for sure a 5.3 can't. 
Wonder if they will come up with an undersquare inline 6 with the same camshaft technology and make that an optional engine? 
The 6.2 is good for mid 5 second 0-60 mph runs stock. Not arguing, just thought you may have had a typo there.
I've actually run as low as 5.1 seconds and that's with 33" tires. ( And a tune)

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Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted
7 minutes ago, michigan2500hd said:

I don't see how the egoboost crushes the 6.2. I've never had one able to hang with me yet. As for the 2.7 it's just downright silly when they line up and think they have something cool. One of my favorite things to do is dust the blue kool-aid drinking crowd who listens to Fords oral crap.

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Just how many of the yet to be released 2.7 4cyl trucks have you had "line up and think their cool"?  

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