Cold Air Intake (CAI) on 2013 6.2L - worth doing?

[Nautilus571]

Ok, let's talk about facts and unreasonable mileage/power gains "claimed" by the manufacturers and users of aftermarket filters.

CAFE, Corporate Average Fuel Economy, requirements by the US Government have essentially killed the low-hanging fruit of easy power gains. In the never-ending quest to improve economy of their fleets, the manufacturers have done/investigated all the easy things. And the manufacturers have billions of dollars they spend on R&D and testing. And hopefully we can all agree that increasing MPG is the same thing as increasing power, right? You're either making more hp while using the same amount of fuel or you're making the same power while using less fuel.

Therefore, there's nothing out there for a modern engine that's going to substantially improve power or efficiency that's cheap and/or easy. It's all been tested and rejected.

Example: The Chrylser/Fiat/Stellantis corporate 3.6 motor was originally designed to use 5w30 oil. Always chasing MPG improvements, testing revealed that 5w20 provided the same protection but the thinner viscosity oil was easier to pump and improved mileage by a tenth or two. So guess what? Stellantis now recommends 5w20. Why? Because when you build 500,000 engines, and can improve their MPG by a fraction, it makes a difference in your CAFE.

If there was an air filter that could improve mileage by a huge amount, say 2 MPG, don't you think the manufacturers would all be using it? And given their buying power and the sheer numbers of units, wouldn't they be able to buy them much more cheaply than in the aftermarket? Stellantis changed oils for a few tenths of a percent increase in MPG. You think they wouldn't JUMP at a chance to increase their fleet MPG by 14%?

CAIs are snake oil. Sure, they make the engine sound better, but that's all they do.

Just providing my personal experience using the CAI unit. About 2mpg improvme y in city. Again, just my personal observation.

 

[Marky Dissod]

Just providing my personal experience using the CAI unit.
About 2MpG improvment in city. Again, just my personal observation.

What year make model and engine size (since it's not in your sig)?
Which cold air intake, specifically?
Are you using the OE air filter, or the filter that came with the cold air intake?
Any other variables we should know about?

 

[Doubeleive]

my results of a CAI are it makes a nice ruimble so it sounds good so I push the pedal more because I like the rumble = decreased mpg. just how it goes.
95% of how many miles per gallon you get are based on how you interact with the big pedal
I can take your rig getting 25 mpg and bring it down to 8 mpg by simply driving it and making no other modification of any kind......
and if you want to bet on it i will take anyones money

 

[Marky Dissod]

my results of a CAI are
it makes a nice rumble so it sounds good so I push the pedal more because I like the rumble = decreased mpg. just how it goes.
95% of how many miles per gallon you get are based on how you interact with the big pedal
I can take your rig getting 25 mpg and bring it down to 8 mpg by simply driving it and making no other modification of any kind ...
and if you want to bet on it i will take anyone's money

It's so funny, because it's so true.

 

[Doubeleive]

things you can do to increase mpg are
lower it, as much as possible
run really hard tires, infltated properly
increase aerodynamics-any way possible, remove roof rack, etc
decrease weight-remove seats, run aluminum wheels etc
drafting
ease up on the big pedal and roll as much as possible

 

[intheburbs]

Just providing my personal experience using the CAI unit. About 2mpg improvme y in city. Again, just my personal observation.

Specs on a 2021 Denali:
14 MPG city
420 hp

You're saying you saw an MPG increase of 2. So 2/14 is a 14.3% increase in efficiency. That may not be easy to visualize, so let's look at it another way....

Improving the efficiency of an engine means it's doing more work for the same fuel usage, or the same work for less fuel usage. So instead of an efficiency gain, let's pretend it's a power gain of 14.2%. A 14.2% increase on 420 hp is 480 hp. So if I said, "I put this CAI on my truck and now it's making an extra 60 hp!" would you believe me?

I see two possibilities:
1) It's such a crappy filter that it basically has zero restriction and all kinds of crap is getting into your engine
2) Because you're hoping for a mileage gain, you've changed your driving habits.

 

[Marky Dissod]

things you can do to increase mpg are
lower it, as much as possible
run really hard tires, inflated properly
increase aerodynamics-any way possible, remove roof rack, etc

'Lower it as much as possible' @donjetman, did you ever bother to record any MpG improvement?
I won't lower my Z71. I like being able to have enough room to change my oil just by driving onto some 2x4s.

'Run really hard tires, inflated properly'
My tires actually wear pretty well @ 40psi.

'Increase aerodynamics any way possible, remove roof rack, etc'
Hypermiler aficionados attest that the 05-06 front underbumper (with the pill-shaped foglights instead of the previous round ones) reduces drag.
How much it improves MpG, I don't know - but GM obviously did it for some reason.

I recently affixed a rather large coroplast sheet to my Tahoe's underbelly (think plastic impersonation of cardboard) with the express purpose of reducing undercar turbulence.
If it improves MpG, I'll let you know - but since I always drive like I'm in a bit of a rush, it's probably just a partial defense against rust.

 

[Marky Dissod]

You're saying you saw an MPG increase of 2. So 2/14 is a 14.3% increase in efficiency.
That may not be easy to visualize, so let's look at it another way....

Improving the efficiency of an engine means it's doing more work for the same fuel usage, or the same work for less fuel usage.
So instead of an efficiency gain, let's pretend it's a power gain of 14.2%. A 14.2% increase on 420 hp is 480 hp.
So if I said, "I put this CAI on my truck and now it's making an extra 60 hp!" would you believe me?

No, because you skruewd up the maths.

The following statement is true
"A 14.2% increase on 420 hp is 480 hp"
at or over 5000RpM.

Comparing overweight housecats to jaguars, or MpG gains to power gains, is not like comparing oranges to tangerines.
More like oranges to lemons.

Since MpG gains typically occur UNDER 2400RpM, a gain of 6 horses would be difficult but not impossible to believe.

 

[donjetman]

@Marky Dissod , I never said anything about lowering?

Over the yrs I've posted here all my mpg findings trying 87, 89, and 91/93.
I may have eeked out a little more mpg running 0w-20 oil.

I haven't tried anything else in search of mpg.

 

[Doubeleive]

'Lower it as much as possible' @donjetman, did you ever bother to record any MpG improvement?
I won't lower my Z71. I like being able to have enough room to change my oil just by driving onto some 2x4s.

'Run really hard tires, inflated properly'
My tires actually wear pretty well @ 40psi.

'Increase aerodynamics any way possible, remove roof rack, etc'
Hypermiler aficionados attest that the 05-06 front underbumper (with the pill-shaped foglights instead of the previous round ones) reduces drag.
How much it improves MpG, I don't know - but GM obviously did it for some reason.

I recently affixed a rather large coroplast sheet to my Tahoe's underbelly (think plastic impersonation of cardboard) with the express purpose of reducing undercar turbulence.
If it improves MpG, I'll let you know - but since I always drive like I'm in a bit of a rush, it's probably just a partial defense against rust.

Ya doing all those things is not for everyone but for those that want to hyper it sure it works, I noticed a huge drop in mpg on my Silverado when it went from a 4/6 drop to a 4.5 lift.
I push the gas pedal too much so mpg goes out the window, my average is probably 9 lately, regardless of the vehicle driven
silverado right now is probably at 8.1 and the yukon is around 9, nothing wrong with either one, they run perfectly, it's the driver......