The kd4crs/Power Hungry/Gotts Mod (revisited - and with pictures)

[Jackpine]

OK - I've been reading about this approach to a CAI mod long enough that I decided to try it. Here's what I did - and I take no credit at all for any of this, it was just my implementation of the excellent ideas put out by people that came before me.

In the 2004-2008 trucks, the intake snorkel has only a 2" diameter at the end where it goes into the fender well. Other than that, it's a Cold Air Intake - so, the goal is to increase the intake opening.

We start with the intake ducting. Remove the holddown bolt (red circle) in the picture below and pull the snorkel out of the fender wall (red arrow). Once you do that, you can pull the duct away from the filter box. It will make a lot of noise that sounds like something is breaking - just smile and ignore the bad sounds.



Now that you've got the intake duct out, turn it over and you'll see two rectangular "bumps" at each end of the bellows that look like they might be "release tabs". They aren't! Instead, they sit over raised areas on the inside tube that act sort of like "tire irons" to separate the bellows from the other parts of the ducting. I separated the bellows from the duct using the circled "bump" in the picture below. (Notice I like to work on the tailgate of my truck). :o



To do this, I put the duct between my knees and then twisted the base of the bellows (where I'm holding it with one hand) all the way around, and it comes right off. (I had to use two hands to do this, but in the picture, one hand was holding the camera).



Now that it's off, you can see the duct opening, which is 3" wide here and the little square bump at the top that was the "tire iron".



Compare the 2" flared opening of the snorkel that fits inside the fender with the 3" opening of the duct upstream of the bellows and you see why the engine might have trouble getting enough air at WOT.



I went to Home Depot and bought a 2 ft length of 3" ABS pipe and a 3" to 3" rubber coupler. I wanted to make sure my new duct went into the fender as far as the original snorkel, so I marked my new 3" tube with a white line to match the gasket position.



Now we have a complication. The hole in the fender is an oval, about 3 1/8" high by 3 1/2" wide. There's actually a small "lip" inside this oval too and I got rid of that lip with a Dremel grinding wheel. The resultant hole is now closer to 3 1/4" high and 3 1/2" wide. (Ignore the dirty fender wall). :o



The hardest part: I had to reshape the end of my new snorkel tube back to the white line to match the 3 1/4 x 3 1/2 oval opening. I used a "Mouse" sander, pictured here with the end of the tube that I shaped.



Here's the finished tube, looking straight down the intake end. The outer surface is cut down so it will just fit into the fender opening. The inside opening is a true 3" intake.



The new snorkel tube will have to be angled slightly from the rest of the intake to fit into the fender properly. (It needs to enter the fender at close to a right angle), so, the other end of the tube was cut at an angle try to match the truck's tube opening angle. The length of the new snorkel on the long side is 12 1/2 ". The length of the short side is 12".



Here, I've joined the two pieces with a 3" to 3" rubber coupler. Leave the "hose clamps" loose for now.



I put my new snorkel into the fender (at a right angle) and it goes in right up to the line where I stopped shaping it. It's actually through the second hole in the inside of the fender at this point. It fits quite tightly through the opening, so I'm not worried about it getting "warm" engine air.



Next, I reinserted the stock intake into the filter box opening and reinserted the hold down bolt. This pulled the new snorkel out of the fender a bit.



I worked with the snorkel to redirect it back into the opening as far as possible. It's not quite perfect, but I think it's good enough. (A "bellows" connector would be ideal here). Once I got the snorkel in place, I tightened the hose clamps.



This is the finished assembly. A true 3" CAI for about $13. Best of all, I can return it to stock in just a few minutes if I want to.



I've disconnected the battery overnight so the PCM will learn a new LTFT strategy and whatever else it has to learn.

So now, Bill: is there any thing wrong with this setup and, I don't need new tunes, right?

And please, this was not an attempt to one-up anyone. I have not seen a pictorial for the 2004-2008 models and this is my feeble attempt to put into practice what other, brighter people have been talking about for my model truck.

I hope it can be useful.

- Jack