Hello, H-T!

My boy has a 100% stock 5-speed 1998 Civic DX hatch and wants to know if his 4-2-1 Header + downpipe combo will bolt directly up to his stock mid-pipe without modification.

I think it might need a reducer to fit but am not sure. It's 2.5 inch on the exit side of it.

Before any flaming starts, this is only to replace a cracked header and inefficient cat which is being deleted. Thank you!

 

The 98 exhaust setup was kind of weird, with cat attached directly to the manifold, so with your header/down pipe an adapter will be needed to go from it to the "b pipe", any good muffler shop should be able to make that for you with the proper ends to fit both the new down pipe and the stock b pipe. 94

 

If it's 100% stock I personally would keep it that way. The manifold/cat combo is expensive but it will bolt right up and work properly.

-Amp

 

Sorry have to flame, do not delete the cat. That car is going to sound like a nest of bees. Just buy an ebay header with the high flow cat and an ebay catback.

I'd prefer you just buy a Dorman replacement manifold with cat for $200 and keep everything stock. Modifications that decrease drive ability from stock, i.e. loud exhaust, greatly reduce the cars resale value. Why bother letting everyone know you're hitting red line to get up to highway speed