looking for a little advice for an intake tube size

[mntb]

I'm looking for a little guidance.
Our TB has the 5.3l V8.
I'm looking to make my own intake/ replace the factory intake tube while keeping the filter box.
I'm not sure if a 3in or a 4in tube would be better. I have the pieces to make an intake in both sizes. It's abs plastic tubing.
I have searched and can't find any recommendations or best size to use.
I don't feel like paying $100+ for something I can put together myself. I already have the filter and pieces to make my own. I just need to find out which size is best.
I'm just looking to help the engine breathe a little better.

Any help is appreciated.
Thank you

 

[Wooluf1952]

Welcome

In case you haven't heard:
http://gmtnation.com...eres-the-story/

Try looking at the Pro made CAI's and use their sizes.

 

[dmanns67]

All aftermarket intakes I have seen for the 5.3L and 6.0L are 4" intakes. What is the size of your OE intake tube?

 

[Capote]

3" for 4.2, 4" for 5.3/6.0

 

[Mooseman]

This post will help you. I used the same thing.

http://gmtnation.com/forums/threads/ascender-limited.11731/page-2#post-342533

 

[mntb]

Thanks for the help.

I believe the factory intake is 4" on the throttle body side and 3.5" on the mass air flow sensor side. But it changes to an oval in the middle.

I'm assuming those pieces were all rubber elbows plus a hard piece between the two pieces. Correct?

I have a 4" 90 degree elbow, a 4" 45 degree elbow, and a few 4" rubber couples. The elbows are abs plastic.

Would these pieces still work? I imagine that the clearance between the intake and the fan is an issue, correct? And that's the reason for the trimming?
I've had the intake off before, however I don't remember seeing a vacuum line connected to it. I'll have to look again.

I'd like to delete the resonator inside the air box as well.
How have you guys plugged the hole between the filter and the mass air flow sensor? Can I replace that tube or just put the filter directly on the mass air flow sensor?

Again, thank you for the help.