ok, just got the swap all done and installed into 94 civic coupe w/ apexi n1 full catback.. the headers from the b18c1 are about 5 inches to short so i know we need a custom pipe for that..

can i put the o2 sensor on the custom pipe cause the plug is on the bottom of the engine?

 

yup..ive done that on a OB II civic

 

when i dropped a b18 in my 92-95 coupe that i had the header was also very short . i spent $240 for random technologies to custom make me one with a hole for the o2 sensor . two weeks later the cat rattled like crasy and i had to punch it out because all the honey combs broke . dont go this route . have a shop make you a pipe with a fitting for a o2 sensor . hope this helps !

 

Use an Si header..... bolts right in and has a bung for the o2 sensor in it.

Joe