Looking for some opinions on my up coming exhaust purchase for my '01 SC. I already know I'm going with a Ravin R33 (Yep, minds made up, no opinions needed there). Question is do I go with 2 1/2" (stock diameter, right?) dual or 3" single (3" from cat back)?

 

Most people are saying single 3" will give you the most torque with Magnaflow compared to duals. I would guess that its the same for ravin as well. Somebody else will probably verify this.

 

Call Gibson, Magnaflow or Borla's 1-800# (yes, I did in fact call them all), ALL OF THEM say that a single 3" exhaust makes more power than duals. Since their dual systems cost more and they're telling me to buy the less expensive one, I'm inclined to believe them. My friend who's a vehicle mechanic for the state of NJ said the same. I've never owned duals and see no reason to start now.

KC-10 FE out...

 

In determining the pipe size, it's important to factor in the size engine you have:

For example:

5.4L SI/SO =3" diameter piping or SI/DO =2.5" diameter piping

4.6L SI/SO= 2.5" diamter piping or SI/DO=2.25" diameter piping

4.2L SI/SO= 2.25" diameter piping

Note that these are just examples. Just know that trucks with larger engines can get away with larger pipes as opposed to trucks with smaller engines if you want to maintain your low end torque. I've been thru all this in the past.