Intake Diamater
 

Im getting a bypass valve for my 95 civic ex, i already have the aem cold air intake installed, i need to know the pipe diameter so i know what size bypass valve to buy

get out a measuring tape, remove the filter or a rubber piece, measure the pipe.

depends on the cai that you bought but I think its 3" but dont call me on it if im wrong...mines 3"...then again I have RS Akimoto

Nope. 2.5" for the 92-95 EX's.....
http://coximport.com/store/20-401s

My intake is a 2.5". I want to get the 3.0, but it's not CARB approved.

The bypass valve is a waste of money. Use the money and take your girl out instead.

Waste of money? Not hardly. I can speak from experience. My car got hydrolocked in less than 7" of water. It doesn't take the 15" that AEM claims on the sticker. And yes my fenderwell inserts were in place.

i was waitin for you to say that

yeah and i live in pa, where weather is eratic