how tight should it be at the flanges where the manifold meets the downpipe and where the midpipe meets the cat-back?

I had to remove the exhaust to mess with the tranny today and now that I put it back together it is leaking again.

I thought i had it tight enough. could it be too tight?

I noticed it wasnt very tight when I took it off but it wasnt leaking either

 

check the gasket..
u may need new gasket.

 

As tight as you can make it without breaking or stripping the studs/nuts.

 

^^good way to break stuff

the manual calls for 32.5-39.7 lb/ft, but since it's all used, i like to add an extra 5-10 lbs to account for stretch.
a good trick to keep your dp bolts from coming loose is to get a really thin washer and bend part up over one of the flat sides of the nut....you just created a locknut--works every time.

only hard part is finding a washer thin enough to bend easily. auto-bone usually won't have them. try napa or a bolt shop.

 

Here comes mr. know-it-all...better move out of the way for him...

What did I just say? I said as tight as you think you can make it WITHOUT breaking stuff. Fasteners have stretched and flanges have warped and disfigured a bit on these old cars, so you need a lot more than what the manual calls for in many cases. Also once everything heats up the dimensions change so being extra tight when cold is not as bad as you may think.

Perhaps you just have to have a feel for it...I almost never break anything, and almost never have leaks at flanges.

 

wuzzup with being all bitchy?