Might consider a header, I installed an LC Engr. header and it has 2" tubing from the collector back to the cat:
http://www.4crawler.com/4x4/CheapTricks/EngineMods/index.shtml#Exhaust

I then made up my own cat-back exhaust, cutting off the stock pipe after the post-cat bend and using sections of straight and flexible s/s tubing:

http://www.4crawler.com/4x4/CheapTricks/TailPipe.shtml

Or just keep the stock downpipe and go bigger after the cat. I did that initially and it seemed to work fine.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
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