Alright, my friend just swapped a B16A SiRII into his 97 Hatch. Right now it is running with the stock B16 Exhaust manifold and stock DX exhaust system.
He purchased a JDM 4-1 header and an APEX muffler but he's heard different things about this setup on a B16A motor.

I've heard two setups with the JDM 4-1.

1) JDM 4-1 + straight pipe + 2.25" b pipe + APEX N1 Muffler
2) Stock B16A Manifold + straight pipe + 2.25" B pipe + APEX N1 Muffler

What's the best setup, what setup do you guys run as far as headers/exhaust goes? Let me know ASAP because we're going to a muffler shop tomorrow?

 

i had the same motor in my 92 4dr civic. b16a sir2, y21 lsd trans. with a greddy 4-2-1 header, test pipe and tanabe racing medalion exhaust i dynoed at 147whp 102trq. my best 1/8 time was 9.51 @ 75mph. 2.31 60ft. the greddy header wasnt the best, it had a slight dip in torque between 3500 and 4700. maybe a vafc wouldve help tune that out. i also ran a dc 4-1, both the regular colector and the jdm 2.5 collector. the regular 4-1 i liked better then the greddy. the jdm 4-1 i really liked. it made the motor pull really strong during vtec with a slight sacrifice down low. only problem i had with the jdm 4-1 was road clearance. it hung too low to the ground. oh and i ran the test pipe with all 3 headers. well hoped that helped

 

So the gains with the JDM 4-1 on the B16 outweigh the sacrifices? That's what I'm thinking...