New GM HD pickups - Air intake design

[DoubleWasp]

Originally Posted By: supton
Originally Posted By: DoubleWasp
I'm skeptical for a few reasons:

1. No performance data......at all.

2. How do you give "Ram Air" to a turbocharged engine? Isn't the high-speed turbine doing enough of the air-ramming all of its own?

3. What is allegedly going on in that truck's fender that the air coming in from there is heated, unlike the hood scoop air?

4. How does ram air work, when you have a 180 degree turn to create an intentional air-stall?

5. How does ram air work when you having a gaping opening in the fender, ready to bypass any excess air forced into the airbox?

6. How exactly is there so large a difference between ambient air temperature and this superheated air from the fender that the engine is supposed to run cooler? WHat happened to the radiator and transmission cooler? We don't design those to regulate engine and transmission temps anymore?

Last but not least:

This is a turbocharged engine. The air coming into the filter box is going to be compressed and superheated by the turbocharger. Intercooler design is going to play the largest factor in ultimate IAT's.


I'm throwing up the Bravo-Sierra Flag on this one. Obviously a case where they called in the engineers to help make tangible function of something they so clearly added for purely styling purposes.



My two thoughts: they seem to be very interested in dry air also. I'm not sure why. But if they could remove moisture from moist air then they could have the same kind of air going into the engine under all conditions (humid or dry), leading to more consistent engine performance. Alternatively, seems to me that in order to heat up moisture you "steal" from the combustion heat.

Also, wasn't there an issue for Ford Ecoboost owners with condensation buildup in their intercoolers? I think I heard about VW TDi's having it also. Hydrolock is a very bad thing.

Finally, while the intercooler is meant to drop intake temps, it seems like there is only so much it can do. Under the most demanding conditions perhaps they couldn't size the IC large enough. Thus, if they could eek out a few more degrees of drop in the hood, perhaps that helps.

Dunno. The ram air effect on the engine does sound like marketing. I know under load the engine is moving some air, but the turbo is supposed to be doing all that work (and for free).


I think they are over compensating a bit I'm driving home the message that the intake will not be guzzling water from rain or mist.

I must admit that my eyes would pop a little bit if I were watching a ram air scoop just swallow up water during a torrent.

 

[440Magnum]

Originally Posted By: supton


My two thoughts: they seem to be very interested in dry air also. I'm not sure why. But if they could remove moisture from moist air then they could have the same kind of air going into the engine under all conditions (humid or dry), leading to more consistent engine performance. Alternatively, seems to me that in order to heat up moisture you "steal" from the combustion heat.


The effect of moisture in combustion air is a lot more complicated than it might seem. Liquid water does lower inlet temperatures nicely, which is why it works so well as an anti-detonant, but it displaces combustible air/fuel mix at the same time. On the other hand, it also undergoes a LOT of expansion when its heated by combustion, so it is active as part of the working fluid that pushes the piston down.

It really is only a net advantage to have damp or even "wet" (liquid droplets) combustion air when detonation is an issue. Then it suppresses detonation and lowers peak combustion temps so you can run optimal timing and get the benefit of water vapor's expansion rate.

But this is a DIESEL. Detonation is never an issue, so the driest possible air to get the most oxygen into the cylinder at the lowest possible temperature before the fuel is added. Dry is always better in a diesel.

 

[badtlc]

A true advancement in intakes would be one that takes cool air in when needed for heavy loading and when under light load it pulls in hot air to improve MPGs.

 

[440Magnum]

Originally Posted By: badtlc
A true advancement in intakes would be one that takes cool air in when needed for heavy loading and when under light load it pulls in hot air to improve MPGs.


You mean like pretty much EVERY thermostatic aircleaner on American vehicles between 1968 and the end of the carburetor era in the late 80s....

Except that they only forced hot air in when the inlet air was too cold to vaporize fuel. Once the engine is hot, there's no need for the intake air to be hotter than ambient.

 

[Jeff_in_VABch]

Originally Posted By: rideahorse
If you have 2 air intake openings. How do you get any ram air affects.


HA!

Don't spoil it for everybody with your science.

 

[DoubleWasp]

Originally Posted By: 440Magnum

You mean like pretty much EVERY thermostatic aircleaner on American vehicles between 1968 and the end of the carburetor era in the late 80s....


And beyond, at that. My 92 Caprice has such a system. I've seen even later Volvos with the same arrangement.

 

[ls1mike]

Bah, I don't get any water in mine and I live in the Seattle area...
Aside from that...testing over the years has proven that the Ram Air affect on the WS6 really doesn't do anything until you get over 80mph. It seems the only thing it really affects are IATs.

 

[SwampSurvivor]

Originally Posted By: userfriendly
Exactly TT; Is that a truck, bus or locomotive?
I know where this topic came from, dummied down GM Authority.
Oh!! We are losing the torque and horsepower race to Ford and Ram.
Horsepower race in the full size pick up market?
The guys lifting their trucks also delete the DPF and chip the Diesels for what ever horsepower is required to snap the driveshaft and drop the transfer case.
The "off road" suspension package can be ordered with 275/45/22s on the 1500s.
Yeah, I'm going off road with 22s. And how can I service the steering after going off road? Can't, there is only one grease nipple on each side.
Ya gotta love those off-road trucks when they have a load in the box with the headlights pointing at the tree tops.


I'd remove the junk to get a truck that not only is more reliable but gets better fuel economy.

But 22s , especially with a 45 sidewall just seems like a reallllllllllly bad idea.

Pick up trucks are now a fashion accessory or some way to enhance your masculinity.

 

[CarbonSteel]

Originally Posted By: supton
Originally Posted By: Merkava_4
It's still gonna be a smelly suffocating fume belching diesel truck no matter what they try to do.
They're pretty clean today, at least until the owners rip off the stuff.
+1 - mine has ZERO smell or fumes and unless heavily accelerating, one would not even know it is a TDI, modern diesels are pretty quiet.

 

[SwampSurvivor]

Originally Posted By: 2015_PSD
Originally Posted By: supton
Originally Posted By: Merkava_4
It's still gonna be a smelly suffocating fume belching diesel truck no matter what they try to do.
They're pretty clean today, at least until the owners rip off the stuff.
+1 - mine has ZERO smell or fumes and unless heavily accelerating, one would not even know it is a TDI, modern diesels are pretty quiet.


The urea smell on the newer ones gives me a massive headache. I used to love the smell of diesel trucks. Not any more

 

[TiredTrucker]

The urea smell doesn't really seem to bother me, the fun part is getting behind one of the newer commercial semi trucks doing a DPF burn off on a pull. That is some nasty stuff. Kinda hard to imagine that it is safer than a little soot. Soot out stacks of computer controlled non emission diesels (like my 2000 factory remanned Detroit 12.7L S60) not like the old mechanical diesels and N/A diesel of days gone by.

 

[artificialist]

Originally Posted By: badtlc
A true advancement in intakes would be one that takes cool air in when needed for heavy loading and when under light load it pulls in hot air to improve MPGs.
Would a diesel engine benefit from that? I thought that once the glow plugs or grid heaters were shut off, the engine had all the extra heat it needed.

 

[TiredTrucker]

If one really wants to improve the cool air to the intake, then put a turbo blanket on the exhaust side of the turbo. Lots of heat radiates from that side and increases intake side of the turbo air temps. A blanket also keeps the heat off the actuator on these newer VG turbos as well, actuator failure is one of the more common reasons for turbo failure. Far fewer problems with a blanket on the exhaust side. I run blankets on all my turbos now. Got 557,000 miles on one of them. On a previous one, lost actuator at about 325,000 miles. After replacing, put a blanket on the turbo. Took it another 630,000 miles without another turbo actuator failure.

 

[mjoekingz28]

What is the heyday of trucking TiredTrucker?


Would you say 2000? Or earlier before Qualcomm?

I thought equipment was great in 2004. Then I stick my nose back n the industry in 2014 and DPF, no idle/auto shutoff, nanny this ninny that, mandatory stops to do the burnoffs you speak of....no more of that sweet smell. But then, I guess that smell of hundreds of trucks idling in a parking lot overnight wasnt all that healthy anyway.

I AM glad to see generators become commonplace so drivers can keep cool or get warm without running the big diesel all night.

 

[Olas]

Originally Posted By: mjoekingz28
What is the heyday of trucking TiredTrucker?


Would you say 2000? Or earlier before Qualcomm?

I thought equipment was great in 2004. Then I stick my nose back n the industry in 2014 and DPF, no idle/auto shutoff, nanny this ninny that, mandatory stops to do the burnoffs you speak of....no more of that sweet smell. But then, I guess that smell of hundreds of trucks idling in a parking lot overnight wasnt all that healthy anyway.

I AM glad to see generators become commonplace so drivers can keep cool or get warm without running the big diesel all night.


Off topic, and I'm sorry to butt in, but, to me the heyday of trucking was in the 50s 60s 70s when Foden 2 stroke diesels were common round here. I still stay in touch with John, grandson of THE Mr. Foden that gave his name and life to the brand

 

[Olas]

Originally Posted By: DoubleWasp
I'm skeptical for a few reasons:

1. No performance data......at all.

2. How do you give "Ram Air" to a turbocharged engine? Isn't the high-speed turbine doing enough of the air-ramming all of its own?

3. What is allegedly going on in that truck's fender that the air coming in from there is heated, unlike the hood scoop air?

4. How does ram air work, when you have a 180 degree turn to create an intentional air-stall?

5. How does ram air work when you having a gaping opening in the fender, ready to bypass any excess air forced into the airbox?

6. How exactly is there so large a difference between ambient air temperature and this superheated air from the fender that the engine is supposed to run cooler? WHat happened to the radiator and transmission cooler? We don't design those to regulate engine and transmission temps anymore?

Last but not least:

This is a turbocharged engine. The air coming into the filter box is going to be compressed and superheated by the turbocharger. Intercooler design is going to play the largest factor in ultimate IAT's.


I'm throwing up the Bravo-Sierra Flag on this one. Obviously a case where they called in the engineers to help make tangible function of something they so clearly added for purely styling purposes.



All valid points except for number two - after the compressor you're right in that it is doing its own 'ramming', but before the compressor as little pressure drop, and as much static pressure as possible are highly desirable to feed the compressor.
It can only compress what it is fed...

 

[TiredTrucker]

I have been driving HD commercially full time since '82. Started occasionally driving dumps, grain haulers, etc in the early 70's. I still haven't found the heyday of trucking. It all depends on individual perception. But I have a 2013 Freightliner with a pre-emission engine in it. No DPF/SCR nonsense. And the qualcomm, I have no problem with. I still remember very well the having to stop and find a pay phone to call someone. That wasn't fun. Things are better on a number of levels than the "good 'ol days". Billy Joel said it well in a song one time... "the good 'ol days weren't all that good, and tomorrow is not as bad as it seems". I would not want to go back to the 80's and 90's in trucking ever again.

 

[xxch4osxx]

Originally Posted By: Miller88
Originally Posted By: 2015_PSD
Originally Posted By: supton
Originally Posted By: Merkava_4
It's still gonna be a smelly suffocating fume belching diesel truck no matter what they try to do.
They're pretty clean today, at least until the owners rip off the stuff.
+1 - mine has ZERO smell or fumes and unless heavily accelerating, one would not even know it is a TDI, modern diesels are pretty quiet.


The urea smell on the newer ones gives me a massive headache. I used to love the smell of diesel trucks. Not any more
I can't stand the smell either, I don't get headaches from it though.

 

[Silverado12]

Originally Posted By: TiredTrucker
Amazing how GM can find ways to make the front end larger and larger, which is a detriment to those of us that actually have to use these pickups in tight places, work sites, farm stuff, etc. I have a 2015 2500 and curse it now and then for having the front end it does. Now they want to elevate the hood even more with a scoop. Glad I will not be looking at another pickup for quite some time. I haven't cared for the bloated front ends of these newer pickups. Wish I could have the same front end on mine as my '98 2500 did. This stuff seems more catering to the "hey, I have a diesel" crowd looking for bragging rights.


I'm with you on that. My 2012 feels like I have no visibility 10' in front and 25' to the rear. In fact, I can't even see my Cruze if I park it directly behind the truck.

 

[Hootbro]

oh god, more "Ike Gauntlet" tests with worthless comparisons in the future.