2010 Silverado Air Box Mod

[mtsusa]

So maybe I'm an idiot for this but I'm constantly trying to squeeze the absolute most performance out of a vehicle. Since the nnbs air boxes are so well designed, I figured it'd be futile to spend $250+ on an intake so I decided to cut out a portion of the bottom of the air box. When I removed it, I noticed the platform it sits on has a hole cut out that leads to the top of the rubber guard inside the fender...and this area seemed to draw in cooler air. Thought it was a good idea at the time.

 

My thought now, though, will aerodynamics be adversely effected? Air pulled in through the stock location travels straight through the slanted filter and into the intake tube...but if the bottom is cut out, will rising air disturb the air flow coming in through the fender wall and create turbulence in the air box?

 

Real curious to hear what you guys think/come up with!

[kdixer]

Personally, I think you are over complicating things. It has been stated before that the intake components are the same for the 4.8, 5.3 and the 6.2. If the stock intake can sufficiently feed a 6.2, then it will have no probelms feeding air to the 5.3 liter. When your truck is rated for 315hp, the 5hp peak you might gain from an intake mod will not be felt. Just add a drop in filter and be done with it. There is no wonder intake that will add massive amounts of power. Realistically, the intake flow is established at the throttle body, so how well an intake flows determines performance for one throttle position (WOT) at a certain rpm and up. After all the 5.3 @ 1500 rpm's will not require near the air it will @ 5500 rpm's.

 

As far as cold air intakes, how much difference are they gonna realistically make with the exception of stop and go traffic. In which case you really do not need tire burning power. I would say at speeds of 20 -30 mph and up the intake air temps are going to be within 1-3 degrees of the ambient air temperature anyways. These are daily drivers, not top fuel dragsters where every .1 seconds mean something. If the intake tube gets heat soaked, how long does it take for it to return to ambient temps at highway speeds? I would guess not very long.

 

This is just my opinion and in no way meant to offend anyone.

[mtsusa]

I do agree, like I said, I'm anal when it comes to getting every little gain possible, however unnoticeable it may be

 

However, I guess I should've rephrased that...do you think I'm actually decreasing performance from stock by introducing turbulence into the airbox?

[kdixer]

I do agree, like I said, I'm anal when it comes to getting every little gain possible, however unnoticeable it may be

 

However, I guess I should've rephrased that...do you think I'm actually decreasing performance from stock by introducing turbulence into the airbox?

 

 

No. The air is pulled into the intake, not necessarily pushed. What ever "turbulance" you introduced to the filter box will be dissipated by the filter. Like I said before, the intake flow is dictated by the butterfly valve in the throttle body. So even if you had a ram air intake, the flow would be restricted and/or rearranged at the throttle body except at WOT.

 

But I do not think you necessarily helped anything either.

[Black02Silverado]

I don't think it would make any difference. What might come into play is water entering the air box. I have not taken mine out so I'm not familar with how it looks in that area of the vehicle. Of course you would have to be running through some serious water but just a thought.

[Z45]

For normal driving not even a cold air intake will provide any increase, only at WOT, maybe.

 

So all these mods are fruitless unless you are racing....save your money.

[mtsusa]

Ah that's why I'm saving my money by modding it myself

 

It doesn't appear that water can get in there. I'm only curious of this because my mileage decreased since I did it.

[kdixer]

One thing you need to consider while theorizing about intakes is this:

 

The air flow thru the engine is not constant. It is constantly dissrupted due to the intake valves closing. Each cylinder only draws air every other turn of the crank. And this happens for each of the 8 cylinders. So how do you imagine the flow is inside the intake manifold? You might as well take most of what you know about laminar and turbulent flow and throw it out the window.

 

I had a proffessor in college that believed in open book tests. His theory was "We are not reinventing the wheel" that work has already been done for us. He was not asking us to remember formulas. He simply wanted us to be able to apply them.

 

GM has already designed an intake system that works quite well, the mighty Vortech, and they installed one on your truck.

[mtsusa]

One thing you need to consider while theorizing about intakes is this:

 

The air flow thru the engine is not constant. It is constantly dissrupted due to the intake valves closing. Each cylinder only draws air every other turn of the crank. And this happens for each of the 8 cylinders. So how do you imagine the flow is inside the intake manifold? You might as well take most of what you know about laminar and turbulent flow and throw it out the window.

 

I had a proffessor in college that believed in open book tests. His theory was "We are not reinventing the wheel" that work has already been done for us. He was not asking us to remember formulas. He simply wanted us to be able to apply them.

 

GM has already designed an intake system that works quite well, the mighty Vortech, and they installed one on your truck.

 

 

Kudos on your wisdom there, Eddie.

 

Still wondering why my mileage would go down, though...same trip, same driving habits, etc.

[mtsusa]

Something else I just noticed...it rained this morning so I went out to look at my air box. Now I couldn't see the hole I cut in the bottom of the intake (which is protected from water getting splashed up from the road) but the foam that surrounds the stock inlet is damp. Guessing water could've dampened the filter?

[mxdirtrider56]

Something else I just noticed...it rained this morning so I went out to look at my air box. Now I couldn't see the hole I cut in the bottom of the intake (which is protected from water getting splashed up from the road) but the foam that surrounds the stock inlet is damp. Guessing water could've dampened the filter?

 

It's possible. That's a big reason I don't want a CAI. Many of them aren't sealed as well as the stock box which provides the oppurtunity for more dirt and water to get in. IMO you should just stick with the MIT you installed.

[tanked_darren]

Something else I just noticed...it rained this morning so I went out to look at my air box. Now I couldn't see the hole I cut in the bottom of the intake (which is protected from water getting splashed up from the road) but the foam that surrounds the stock inlet is damp. Guessing water could've dampened the filter?

 

NO ITS FINE, that's just a pre-filter.

 

It is fine mine gets wet all the time from road mist (driving on the freeway)

 

I've never had a airfilter go bad from that getting damp yet, (97,000kms)

 

 

And why the hell would you butcher a perfectly good airbox??!!

Don't you think GM would have done it from the factory if it was better that way?

[mtsusa]

Something else I just noticed...it rained this morning so I went out to look at my air box. Now I couldn't see the hole I cut in the bottom of the intake (which is protected from water getting splashed up from the road) but the foam that surrounds the stock inlet is damp. Guessing water could've dampened the filter?

 

NO ITS FINE, that's just a pre-filter.

 

It is fine mine gets wet all the time from road mist (driving on the freeway)

 

I've never had a airfilter go bad from that getting damp yet, (97,000kms)

 

 

And why the hell would you butcher a perfectly good airbox??!!

Don't you think GM would have done it from the factory if it was better that way?

 

 

 

Well, I will say that this air box has 2 openings leading to the fender with a spacer in the middle, while the GMPP CAI (designed by GM, of course) cuts out the spacer and enlarges the opening. Yes, this is minimal but my point is they did design a "performance" product with a great opening.

 

I thought the hole in the bottom would allow another location to draw in cooler air...similar in concept to the Volant air box for this truck.

 

That's why the hell I did it

[kdixer]

They also make GMPP exhaust tips and I am pretty sure those things do not do anything for performance. Soemtimes companies make stuff because people want it, not because it is really much better. Some people just prefer the looks and sound of an intake system.

 

My stock intake and K&N drop in sounds and performs just fine. There are millions of miles worth of research accounted for on modern vehicles. If there were mpg gains to be had, gm and other manufacturers would be doing it.

 

What is the hp difference between an engined dyno'd on a 40° day and the same engine dyno'd on a 90° day? Anybody know? That should put things into perspective for people wanting big gains from a CAI kit.

 

Edit:

http://www.truckinweb.com/tech/0103tr_proj...ning/index.html

 

"According to Bell, a general rule of thumb is that for every 10 degrees of air temperature (cooler or hotter), there is a corresponding 1 percent of horsepower increase or decrease."

 

So according to this article, if a cai can reduce iat 10° it will be good for 3.15hp on the 5.3 liter. That would be a huge feat for cai to achieve in normal everyday driving.

[mtsusa]

They also make GMPP exhaust tips and I am pretty sure those things do not do anything for performance. Soemtimes companies make stuff because people want it, not because it is really much better. Some people just prefer the looks and sound of an intake system.

 

My stock intake and K&N drop in sounds and performs just fine. There are millions of miles worth of research accounted for on modern vehicles. If there were mpg gains to be had, gm and other manufacturers would be doing it.

 

What is the hp difference between an engined dyno'd on a 40° day and the same engine dyno'd on a 90° day? Anybody know? That should put things into perspective for people wanting big gains from a CAI kit.

 

Edit:

http://www.truckinweb.com/tech/0103tr_proj...ning/index.html

 

"According to Bell, a general rule of thumb is that for every 10 degrees of air temperature (cooler or hotter), there is a corresponding 1 percent of horsepower increase or decrease."

 

So according to this article, if a cai can reduce iat 10° it will be good for 3.15hp on the 5.3 liter. That would be a huge feat for cai to achieve in normal everyday driving.

 

 

That is interesting...good to know my anal nature isn't getting me very far even if I'm ever right

 

I do question one thing though...GM and other manufacturers have to strike a balance between performance, economy, sound, etc for the common driver, so I feel some things are compromised to a degree. Albeit small differences, I still noticed enough of a difference in fuel economy in my truck with my MIT + exhaust to save $180/yr in gas (of course it's because I drive an insane amount of year). Seeing as $180 was about my initial investment, I feel content with my investments...

 

For the record, though...would my cutting a hole in the base of my stock intake box have a similar effect (as I thought) to the hole in the base of the volant filter boxes? I'm not asking if it'd actually give me noticeable increases, just if the concept should function similarly.