[whoaduck]

I thought only the JDM ITR headers had the 2.5" collector. I thought that is why it couldn't pass smog. But in order for the USDM ITR to pass smog, wouldn't it require a smaller collector? I'm not sure, could someone please clear this up for me.

Thats what I always thought. Doesn't the Type R header hang down lower too? Just wondering.