Why Do Some Intercooler Pipes Have "Breather" Pipes?
 

So I'm looking to buy an intercooler kit for my turbo conversion for my 1.6 NA. From looking at a few different kits, I notice that some kits have "breather pipes both on the turbo inlet pipe and alos the inlet pipe that attaches just before the throttle body.

Any reason for this?

Examples:

No pipes:
http://www.cxracing.com/mm5/merchant...ry_Code=ICKMZD

Pipes:
http://www.universal-intercoolers.co...tomers/Mx5.php

Thanks guys

Well the connection near the throttle body is for your idle air valve. It's pretty necessary since just putting a filter on it won't stop and boost from leaking out if it doesn't close all the way. On that note, I have a breather on mine but I put a huge pcv valve in between the idle air and the filter so that it only sucks air in and lets nothing out. The connection on the exhaust side is pollution control. Venting to atmosphere works as well but horrible smell.