Exhaust pipe for 4905

[chris4905]

Bryan,

I'm not an exhaust specialist but I don't think you want to create back pressure......just the opposite, you want unrestricted flow.

Check out this website, I think it will have all the specs, measurements, and parts you will need:
http://www.walkerheavyduty.com/catalog/catalog_default.asp

The 5" is a standard for the large vehicle industry, and it is probably larger than the OEM currently on your bus.  I used 5" exhaust piping and muffler inlet/outlet on my 4905 with the 6V92, and the DD mechanic gave me a thumbs up. (for what that's worth).

Have fun looking at the site, buy the way it also has "backpressure" specs.

Chris