Hi ,
In an attempt to make a relatively quiet ( heavy is ok , loud isnt!) exhaust system , I am thinking two or three BORLA XR1's , one at the back and one or two under the car . Now I know one will fit under there easily , but has anyone got two in there ? if so can you please post pics and say which of the two universals u used ( Case Length 12" ,Case Shape Oval , Inlet Diameter 4" or the one with the 14 " Case Length) ? thanks alot guys .

 

Try www.coastfab.com they sell mufflers. I have one of there 4" round ones and a magnaflow at the end. Everyone says my car is much more quiet now then last year with a 3" exhaust. And i run a bridge port as well this year.

It's abit more expensive then other mufflers but they realy do work to kill the noise.

JT

 

im runn a round instead of oval midpip with the HKS Drager 4'in exhause, alot quiter then my old set up which is a 4in DP, to a 3in mid, to the 4in apex-i GT spec. it is quite esp when crusing.

 

I have ONE Borla XR1 muffler at the end of my 4" turbo back. I have yet to start the car up but I'm very impressed with the quality. I was hesitant at first with the 200ish price tag but I'm very pleased with it so far. I know you're looking for sound information but I figured I would let you know my initial thoughts.

 

CONGRATS ON GOING 4". I WILL START THE INSTALL ON MY 4" SYSTEM THIS WEEK. HERE IS THE LINK
https://www.rx7club.com/single-turbo-rx-7s-23/4-complete-exhaust-system-build-770041/