I own 89' crx D16A9 (130 hp) and planning to upgrade my exhaust. Is 2 1/2" not too big? 2" too small? Not going to swap fot B16A or mess with turbo, but chiptuning and stuff is on the way. I plan about 150hp. So - how big exhoust should it be without cat, only one free flow resonator?

 

well more power more air flow needed...but again it a D16 so 2 1/4 should be fine.

 

If your going to put a b-16 in it later just not do you exaust yet. Put the b-16 in then go with a 2 1/2in if your not going turbo.

 

I would almost say that 2" would be fine for your setup, even on my turbo setup I only ran 2 1/2" and when I was N/A it was very boggy (On a stock B16).

 

yeah i got 2 1/2 as well and it is kinda boggy like stated above but when you race or just get on it, it works well and i think it gives you a little bit at the top, but at the bottom i guess not so good. light weight cars like ours dont need a lot down there but it cant hurt. especially if your tryin to break your time or something

 

2" is fine, good gains all around, no more than 2 1/2".