Actually Hammer did a test of metal versus non metal tubing and found only a couple of degrees difference and nothing that would be noticeable

 

Made another CAI for my 3.7 to 4.7 swap.

 

Looks good, I plan on making one similar but haven't got around to it

 

Hi Guys, I am new so don't beat on me too bad. I just want to offer advice or suggestions to the DIY crowd.
These DIY intakes and some of the aftermarket are cool looking but really miss the point of a CAI.
90* angles kill flow. You are reducing flow and causing turbulence.
If I recall correctly I think 90* bends reduce airflow by 25-30%. It is a matter of friction for the air, less friction = more flow.

Think of a car driving home full speed with no brakes. When the car comes to a 90* turn, what happens? It smashes into the wall and eventually gets turned in the right direction to get home.
That is what air does, it slams into the 90*, farts around and then heads in the right direction.

There has got to be a better route for the tubing. Maybe one 45* heading straight for the fender or like that Ram guys design with a nice long curve. The less acute the angle the better the flow.
And, I don't understand why you would make a "CAI" with no heat shield. Sucking in heated engine air with a 90* bend is hurting performance over stock.

While I am new to Rams, I am not new to the design of DIY CAIs, I have hashed this out and researched a lot with my Buick as I made my own CAI for the supercharger.

And I am a DIY guy, eventually I will visit my local plumbing store to start my own project too.

 

Well when you get around to making your CAI take some pics and post em up! I'm open to making a new one myself

 

Good info dodgebluto. I don't think (for most of us anyways) its a lack of understanding about airflow as to why people do the 90 bends and no heat shield. After lots of reading on the forum, there are several things I would summarize. 1: The hemi hat is so restrictive that removing it and putting 90's in DOES increase airflow. There's a couple pics somewhere of the inside of it, it's got bends and u turns all over the place. 2: Proven power gains (or mpg for that matter) are hard to come by, and most guys aren't heading to the track, so the pleasure of making their own intake, the sound of the hemi sucking up air and any incremental gains they get are good enough for most. 3: Sure sucking engine air isn't exactly "cold", but if you are doing your own cai it's a lot easier to not design a heat shield, and just glue some pvc and a filter together.

All that said, if you come up with a good design using 45's or some other less restrictive system of tubing and integrate a good heat shield into it, you will gain a cult following on this site. Most of the guys will agree that would be an improvement over what a lot have done. Be sure to post up a diy if you do, there will be lot's of interest in it (including me)!

 

I hear you on the feeling of accomplishment and the smile when you hear that cone sucking air through your own DIY intake. While I am LH (lacking Hemi) I see the hat on my 5.9 is restrictive as well. I will report back when I piece together something

 

Can't hear any sucking but it gets the job done.

 

that engine bay looks fantabulous SLT8

 

I just installed an Airaid system on my truck. It now has a C.A.R.B. sticker for us guys in California.
The intake works terrific, along with cat back Magnaflow system.
Before I put the air intake on I was getting 20mpg on the highway. I have now made two trips, one 210 mile and one 285 mile...............and I usually drive 65/70mph. Well................on both trips I got 23mpg. I was totally amazed.
I will see what it does pulling my race car.............before I was getting 10mpg hauling the 4000lb trailer/car.