I just finishd a custom dual 3" into 4" Y pipe and single inlet/outlet bolra xr-1 with 4" in/out and 16 oval case.

this set up is so loud that a cop hear it from inside hes car at about 1300ft from me when I was 50% throttle!!

I want to lower the sound as much as I can, dont plan on paying 400 for the corsa diesel muffler

found these options :
dynomax ultraflow 22572 = 4"/4" , 20" case 9"round .
dynomax race bullet 24233 = 5"/5"., 16" case 6" round
dynomax race bullet 24217 = 4"/4"., 12" case 5" round
vibrant 1154 = 4"/4" ,15" case 5x9 oval

as for magnaflows , the 4/4 in out has a 3.5 core .so its baiscly a 3.5"
any input is much apprieciated
my goal is quite and doesnt sacrifice the flow, this will be my turbo exhaust

 

Those Borla's sounds good but ever clip I have heard it sounded 10x louder than other mufflers. If you can fit that "dynomax ultraflow 22572 = 4"/4" , 20" case 9"round" that would probably quiet it down the most since it has the longest case out of the 3 you listed.

 

what kind of exhaust do you have?

 

Im running a 14" case magnaflow on my 4" system and its not too bad. But I've been thinking about going to a 20" magnaflow. if you go with the Dyno max let us know how it turns out.

 

Stock manifolds and exhaust. I just had the stock muffler replaced with some local special the muffler shop sold me on and dumped it under the bed.

It worked fine when I was NA, it's a huge bottle neck now with the Procharger and all the other mods.

 

TSP recommended two magnaflow to quiet mine down, using the specs listed in my sig line. I can give the P/N if you need it.

 

yes please , note that im going turbos

 

The Dynomax is the BEST sounding muffler I have ever ran. I have them on pretty much everything I own. They diffenately won't hurt your exhaust flow.

 

Where are you getting your information? I have 24"x7" round Magnaflow and it is 4" all the way thru. 12772 I would have gone with the 30" but I didn't have the room under a rcsb. Mine is fairly quiet in cruise mode but gets loud with any input from the skinny pedal.

 

this is the one I looked at 12773

MagnaFlow Exhaust Products - For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles