Yes, I agree that Subaru CATs are very restrictive, but the original post is not talking about the stock tbe. I'm refering to a downpipe with a high-flow CAT vs. a catless downpipe. The difference between high-flow cat and catless in hp gains/loss is very insignificant.Originally Posted by Silentdawn
Please read the thread carefully.AP = AccessPORT. It's a type of engine management.Originally Posted by project_skyline
downpipe + catback = turboback exhaust (refer to the diagram below).
You have an option of running a turboback exhaust with or without high-flow CAT. It does not neccessarily mean catless.