I know that w/ the new 60mm collector, I'll need an after market cat. But which after market cat is out there for this application? I tried fabricating a custom mid-pipe, but it isn't a clean job. The donut makes it all the more difficult. Help!

 

go here --> http://store.hybridgarage.com/
then click on the exhaust link. You'll see the 2.5" cats for the JDM 4-1. There's a few so choose the one that's right for your application.

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