2.5 in, 2.5 dual out. Personally, I think the 18" is plenty loud for me. Granted I have the Magnaflow, but it's really inconsequential. It's aggressive on start-up and while accelerating, but bare noticeable once you hit 40mph and the torque converter locks. Get on it, and you'll hear it plenty. The 11" (or 14" for Maggies/Flows) is just plain loud for everyday driving.

 

so the longer the louder or the short the louder?

 

A shorter/small casing= louder. And yeah, staying 2.5" would probably be best. Going to a 3" pipe may cause some loss of low end torque...

 

Shorter the louder. More muffler = less noise haha

 

Perfect situation where people see things different. I have a 14" long 4" round Magnaflow and it isn't loud enough for my daily driving preferences.

 

Agreed. Different strokes for different folks!

 

My long tubes and 9" (?) Borla/Roush isn't loud enough

 

ok awesome. thanks for the info. I want it aggressive sounding but not hill billy loud. I want it to sound like its a v8. its a work truck and we deal with high end clients and don't want them thinking im a redneck lol


well the borla proxs only comes in a 19. so that settles that.

 

Nothing at all redneck about the sound of Borla. Good clean rich tone no matter the volume.

If you want to fiddle with a Y pipe you can make a SI/DO ProXS with a 14" SI/SO case.

 

the proxs that I looked at that have single in and dual out are all 19. also what is the notch on the exhaust? do I want it with it or with out?

 

Anyone know? Notch vs unnotched? Want to order muffler tomorrow

 

Do you mean offset or actually notched? I'd just do center/dual out for the muffler if that's what you mean. I'm not sure what notching is.

 

X2 I don't know what you are speaking of about "notched". Could you post it here?

SI/DO is only in 19" yes. I was saying you could run a 14" and use a Y pipe to achieve dual tails.

 

check it out on this link.
http://www.borla.com/products/proxs_centerdual.html

they list two of each muffler type but one is notched and other is not. I don't know what that means or what kind I should get?

 

I'm not positive, but I think the notched versions are if you plan on using an exhaust clamp to secure the muffler to the pipe, as opposed to welding it. I'd definitely have them welded on.