B18C swap in 99 EX Civic Header to Cat to Exhaust Help!!! Please!!!

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The Drew

New Member
I ordered a JDM B18C swap from HMO and the motor is a 96. The motor sits perfect but my problem is the following:

- The collector on the JDM B18C exhaust manifold is to big to fit my EX Cat. I think the outlet is 2.5.

what year USDM GSR Exhaust manifold/header do I need to bolt up to my EX cat?

Would it be better for me to get a GSR cat. Which year will fit the 99 EX and bolt up to an aftermarket header?

From what i have seen the 94-97 GSR Exhaust Manifolds/headers are longer and have an o2 bung for the primary o2 sensor in the header. The 98-01 GSR are shorter and the primary o2 is located on the GSR Cat.

PLEASE HELP!!!!!
 
Nevermind... just cut the flange off the aftermarket header bolted it up to the cat and welded a piece of pipe from the flange to the header and tapped in for the primary o2...
 
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