Hey all.....I just got back from Home Depot in my search for plumbing to replace the entire stock intake system from the filter to the turbo. I realize that bigger is better, however it has to eventually reduce to 3 inches to go into the turbo. Why not go as follows....Filter outlet immediatly reduce to 3 inch via rubber adapter from 4 to 3 inch. It completely slides over the filter outlet ensuring NO leaks. Go from the 3 inch side of the reducer (bell type reducer) into the 45* white PVC pipe and slide 3 inch pipe onto that "street elbow" as they call it. Purchase and cut to length 3 inch PVC and use a rubber 3 inch to 3 inch connector directly to the turbo!! Simple, straight and it totally eliminates the factory plastic "bellows" looking system and allows you to continue and do the CCV mod shortly therafter...Please anylize this and let me know any flows in my thinking.....Oh and I will be putting the filter minder on the end of the filter.....Thanks, Dave

 

Two things. First, I wouldn't want to restrict it down until you got as close to the turbo as possible. I'm no expert in fluid dynamics, but I'd think that a 3" reduction right after the filter would have more of a restriction that a 3" reduction right before the turbo. Second, I'm not too sure about using PVC under the hood for your intake. Schedule 20 (thin walled) is designed to resist crushing, but I don't know how it waould stand up to the under hood temps. I'd be afraid that it would become brittle and develop a hairline crack that would leak w/o you knowing it. Then you've got a dusted turbo. Schedule 40 (thick walled) might fare better, but then you're talking more of a restriction due to the wall thickness.

Why not try this. Use 4" exhaust tubing with some 45* connectors. The exhaust tubing is quite thin walled, and will definately stand up to the underhood temps. It also fits directly into the end of the 6637 filter. I've got 2 pieces of the 4" exhaust tubing in my intake (one to connect the filter, second to replace the CCV intake), still utilizing the factory rubber connectors. It works quite nicely.

Just my $0.02.

 

PVC becomes pretty soft and pliable at under-hood temperatures.

Soft plastic isn't something that I'd want to depend upon to keep the dirt out of my intake air system.

Pop

 

So I should get a piece of 4 inch, have a 45* bent in it, and run it from the end of the filter directly down to the reducer that connects to the turbo? Just looking to eliminate any connections and the chance of leaking...Thanks again...Dave

 

yes, that would be correct, but im going to use a 22* elbow instead of 45*

 

Don't know about you guys trucks, but it seems to me that there is a lot of plastic under the hood of my F-350 that's holding up just fine. What's the stock intake tube made out of? I don't think it will be a problem.

Ajd jtharvey is right, keep it as big as possible for as far as possible.

 

The stock intake bits are made of HDPE, which is an altogether different animal than PVC. Its thermal stability characteristics are far greater, and is much stronger in general. You definitely don't want PVC for that intake tube - unless you don't mind sucking it through the inducer.

 

Here is a picture of how I did mine with a piece of 22* 4" exhaust pipe and rubber connector.


http://i26.photobucket.com/albums/c1...D/9cf6f6cc.jpg

 

HDPE does have a 20* advantage over PVC in continuous operating temperature, but PVC is much stronger. HDPE's main advantage is that it is "slicker". But PVC shouldn't be a problem.

http://www.machinist-materials.com/c...r_plastics.htm

 

[QUOTE=kilapapipa]Here is a picture of how I did mine with a piece of 22* 4" exhaust pipe and rubber connector.


http://i26.photobucket.com/albums/c150/kilapapipa/2000%20PSD/9cf6f6cc.jpg[/QUOTE]

Hey Kilapapipa: I called around looking for 4" exhaust tubing (harder to find than I expected). The folks who do have it asked what type of tubing I want (stainless, aluminized or some other I don't recall). What did you use?

Also, they all ask how long I want the overall pipe and where I want the 22 degree bend - any help or just make it long with the bend in the middle and cut down the ends later?

Thanks!

 

two things... first.. you want to be careful when clamping OVER the end of the filter, it CAN be crushed which allows it to COME OFF of the intake tube... it happened to me, that's why i am getting a 4" piece of exhaust pipe to put on the inside of the 6637 AND the inside of the intake tube and clamping onto a PIPE that WILL NOT CRUSH no matter how tight you get the clamps...! also... i used pvc to replace the stock piece when i did my CCV mod, it actually got SOFT under towing conditions and was NOT ROUND when i took it out to inspect it..! i do not think it leaked, but i put the stock setup back on till this spring when i have some time and warmer temps to work in... i'll get something together that is METAL and will stand up to the conditions under the hood..!

 

I actually found a 22* pre-made aluminized fitting for $25 at the shop I went to and it had a beveled end where you would use it in the exhaust system. I brought it home, put it in place and cut a few inches off both ends until it would fit. I had to cut off of both ends to make it work though. It fits but the angle could be a bit better. You might want to fabricate a model with some dryer flex hose or something so they can get it perfect. Hope this helps.

 

I came from a Subaru WRX with a lot of power. In that car under hood temps were a major issue. The problem was heat soak, the metal aftermarket intakes and the top mount IC's would build up heat in traffic resulting in a signifigant loss of power. I am not sure if the same type of problems occur in the diesel world but it is something to keep in mind when building a metal intake. Also with the reduction of the intake from 4" to 3" do it as close to the turbo as possible. Turbos are designed to push air not pull it so the longer you keep the diameter of the intake wide the better.

 

Well I "exhausted" all of my lunch hour on the phone to every muffler shop and big truck place here in Charleston SC and NO place for the exception of one hot rod shop even carries 4 inch exhaust tube. I picked up a single piece with a 45* in it so I will be attempting to fabricate something later this week and see where I stand. As for the CCV mod, I know that is an entirely different animal too, but I have seen 1/2 inch and 3/4 inch hose used. The 1/2 went inside the elbow and if I remember correctly the 3/4 connected to it with a barbed union I believe....any suggestions on the use of 1/2 or 3/4...I know bigger is better, but I just wanted to see which size would connect to the little elbow on the dog house with the least trouble? Thanks for the help and I am still searching...Dave

 

I got my exhaust tubing from my local International dealer. There should be some big rig dealers somewhere in your area. They'll have the 4" exhaust tubing. I used 3/4" heater hose for my CCV mod -- I just went and checked the hose size to be sure. It fit right onto the factory elbow.