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

[Jackpine]

Nice pics, Longshot. I think what you've designed will work just fine. I clamped the bellows on my snorkel tube so that the bellows are nearly fully compressed. That way, if the engine moves, and it will under high acceleration, it won't pull the snorkel out of the fender.

- Jack

[Longshot270]

Thanks, I'm thinking about making some kind of ram but there isn't much space so I'll keep looking at it. I believe that if something didn't have those "stop and scratch head" moments then it's not finished.
Well one thing that is kind of good about the 4.6s is that part of their box is attatched underneath so they dont move at all. But the tube afterwards has enough play to handle any movement the engine makes.

[kennyd]

Hi Jack, thanks for the info on the gotts mod, I think its a logical starting point. Do you think I should also use K+N filter.

Originally Posted by JackandJanet

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

[Jackpine]

Originally Posted by kennyd

Hi Jack, thanks for the info on the gotts mod, I think its a logical starting point. Do you think I should also use K+N filter.

You CAN use a K&N drop in filter. Many people have. I didn't bother because I don't know that it is that much better than the OEM pleated one.

- Jack

[ticopowell]

So i looked at all the intakes that you guys have done, and kinda went my own way to do it. I didnt take any pics while installing it, but i did take a few after so let me know what you all think!

The first is the Y pipe with the 2 flexible hoses coming out.


This pic is of the duct work in front of the tranny cooler


This pic is what the intake looks like from the front. It is kinda hard to see with my cell phone camera, but that is all i had.


Well there it is, it didnt take too long to do, and so far it feel better and the Throttle Response is better at speed!

[Jackpine]

Looks good, ticopowell. I'm not sure that the "ram air" intake part is going to do much (Bill posted something on this fairly recently - talking about the Banks Ram intake), but, if the whole installation seems to be giving you positive results, I suspect it IS. I DO like that flex tubing. Seems a smoother airflow path to me.

- Jack

[ticopowell]

Oh and I forgot that I got a K&N drop in filter in there too
and yeah if the "ram air" does anything it will be at very high speeds, there is a lot of piping to go through and even if it does up the pressure by much the stock hole that it is still hooked up to will dissipate it... well at least those are my thoughts lol. I will have to go see what Bill said about a "real" ram air intake

[Longshot270]

Originally Posted by ticopowell

Oh and I forgot that I got a K&N drop in filter in there too

That will help, I did the same exact thing on my 4.6L

and yeah if the "ram air" does anything it will be at very high speeds, there is a lot of piping to go through and even if it does up the pressure by much the stock hole that it is still hooked up to will dissipate it... well at least those are my thoughts lol. I will have to go see what Bill said about a "real" ram air intake

I have been waiting for someone to notice that bold part on some of the other forums.
I wonder if they make a 3 inch one way flap type valve? (cant think of the technical term right now) If you put that on the stock intake location it would close up if there was a positive amount of pressure, but I dont think it would be worth trying. If you want to see if there is a difference put the MAF and IAT PIDs on the screen with the stock intake and then with the modified. Look at the readings under the same RPM and LOAD(So the 4 you pick would be IAT, MAF, RPM and LOAD).
You would judge improved IATs by degrees from actual temp but the other 3 should be pretty straitforward.
The reason I say both RPM and LOAD is because at 2000 rpm you can have 20 grams/sec of air with minimal load but 70 g/s with increased load. Cruise control will probably be the easiest if you dont want to take a series of datalogs and then stitch them together (not too hard to do though but if your interested but unable you can send them to me).
...hmm maybe I should see the effects of air intake restriction on my intake since there really isn't any info on the 4.6s.

[ticopowell]

Yeah that "might" be worth looking in to, but i think im happy with the cold air from the front of the truck and yeah im too lazy and dont care enough to figure out the differences... my butt-dyno says that they are there so i wont complain and i gotta get my gryphon sent in to be updated to my new truck before i do anything!

[Jackpine]

OK, let's look at the "bold faced" statement:. "if it does up the pressure by much the stock hole that it is still hooked up to will dissipate it.."

Remember, you DO always have constant airflow UP the intake into the engine upstream of the "Y". So, that air HAS to come from somewhere. The amount of air moving is a function of demand by the engine and the supply capacity. If the demand exceeds the supply, the pressure in the tube is reduced. But, having two inlets to the "Y" should effectively add to the supply capability, regardless of "pressure". So, my take on it would be that there would be little to no "restriction" effect. However, any positive pressure provided by the tube going to the "ram" intake is going to be split, and any airflow gain may actually be canceled by turbulent interactions.

I honestly don't know what the effect will be. As I've said before, aerodynamics is a VERY complicated "science", and it's not really that well understood. Most of the "theory" is empirically derived. You would need a lab setup to test the possible gains of this configuration.

- Jack