I am swapping out my turbo D-series for a stock JDM B16 for reliability, my catback is for a turbo car and it's 3". I was looking into getting a high-flo cat and an Inexpensive quiet catback for the car that matches with the stock JDM exhaust manifild. Is the Exhaust Manifold on a JDM B16 2-1/2" (the same as a 99SI?) Also, would a cat/catback designed for a 99SI fit properly on a swapped 99EX? Basic questions, but I just am not sure, Thanks

 

I was also thinking of keeping the 3" Thermal catback, but the neck-up from a stock size cat to 3" would be a problem.

 

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