i have searched and searched and no one has an exact answer. some people say 2.5" or 2 1/4". im trying to install a cutout and i just need to know what size reducer i need.

 

You didnt search well you liar! JK

https://www.evolutionm.net/forums/ev...-diameter.html

 

found that thread and no definitive answer in there. is it 2.5 in some spots does that include the short inlet part? it seems to be skinnier then the rest of the system so im not sure if i need a 3" to 2.5" reducer or a 3" to 2.25" reducer.

i just want to be sure and not have to send back parts, my neighbors have been hounding me since i got my gsc s3's installed lol.

 

Someone measured it on that thread and it almost measured 2.5", just order a 2.5" it'll work.