Considering running mandrel bent true duals with Borla mufflers behind high flow dynatech cats from my shorty's. I might have a deal on the setup I cant refuse. X-pipe is a given.

Do you think 2 1/2" is right for my setup? This should reduce back pressure and drop boost very little, right?
I know it will sound badass.

 

Nobody is running dual exhaust behind the Radix? Is 2 1/2 right or should I go 3" all the way back with X?

 

2 1/2 should be plenty true dual 3" wouldl be too much i would think

 

I ran true dual 2 1/2 with an X no cats and dual cutouts right after the X, it ran alot better then the single exhaust up top. I didnt notice down low since I had a 3K stall. I had bullets for mufflers and it sounded decent, it had a little pop to it that I didnt like but your borlas probably would do away with that. Why are you going with dynatechs? There are those metallic magnaflows out that look damn good and flow well. Why dont you just go ahead and put some LTs on there and make the exhaust for it? I know you live in Cali but you dont have smog for a long time and even then it would only take two extra little pieces of pipe and your shorties to be legal for smog. You would be amazed at the difference a set of LTs will make with cutouts directly off the colletor, you would drop a # or two of boost but you would pick up 30 or mroe rwhp, I would be willing to bet

 

Bill - I have true duals. A custom stainless steel 2.5" y-pipe with magnaflow metallic cats going into an x-pipe. It is mandrel bent all the way out into a dual in/dual out x-flow muffler. I lost about a pound of boost from this.

 

Yeah, I'm gonna go with dual Borlas.
How did it affect your low end around 3-4Krpm's?