Topic: how large is the intake tubing?

[Blingah]

simple question guys, just wondering what the diameter of the K&N etc. intake tubing is?  I am trying to peice together a budget intake and I need a few measurements which I cannot seem to attain.  If things come together I will document avec photos, and one more thing since I am peicing this together, I assume the size of the tubing is 3", do you think there would be any benefit to having a 4" intake since the outside diameter of the TB is 4"......OR do think that would mess with the air/fuel sensor thing on the airbox?

[Main One]

If I was at home right now, I'd run out and measure some tubing that I have taken off.

3" sounds about right.

4" might look cool, but if you are going through a 3" MAF sensor, plus a necked down throttle body, I don't think you would see any performance benefits, and with what little I know about fluid dynamics, would suspect that you may take away a little top end power.

[Blingah]

yea thats what ive thought, so I've already sourced out all the appropriate addapters

[russiankid]

Having anything bigger that the diameter of the MAF sensor is pointless. Reason being is because you're not increasing the size of the MAF, so it will still meter the same amount of air that goes passed it. Stick to whatever size the MAF is, but avoid a lot of bends. Also, make sure you use good material that does not absorb heat.