IIRC, it is something like 35. But if you have a 12 inch driver, PDT (pretty darn tight) is good enough. I have done three or four of them and never had then come undone or be too hard to change back out when required...

 

Says 26ft/lbs

http://www.clubwrx.net/forums/showthread.php?s=&threadid=49789&highlight=service+manual

 

Meh. Just tighten the bolts, as Matt said. It's a downpipe, low pressure.

 

...and be sure to use high temp threadlocker on EVERYTHING.

Only if you never plan on parting out

 

Scrap that idea above, use anti-sieze on all the bolts/studs if you like the idea of making life easier for you in the future and use the proper torque settings.