2.25" is the diameter. You can buy the HFCs from Kinetix that are 2.5" though. I don't and don't plan on switching up the entire exhaust so I went with the 2.25". Thanks for the compliments. The rasp issue has been a non issue for about a month now. I really have to push it right after a cold start to hear anything at all.

 

Where is the best place to buy these?

 

good write up and love the sound

 

Check out the supporting or registered vendors to this forum.

 

Great info.Just a couple tips; aerokroil is the best creeping oil,try a little tightening Nuts and Bolts before trying to loosen them and you might not break them as easily.t he O2 sensor nut size is 22mm.