I can't tell if the exhaust manifold is leaking at the head or where it meets the Y pipe. What is more common?
I also heard someone mention they tend to crack...this true?

 

I would say probably at the head to manifold is more likely.

 

Just MHO.....

But there is no in this world I would pull the LT1 manifolds and not REPLACE them with a set of headers.....
I would get some headers and forget those crappy manifolds

 

I would love to, but:
1. I'm broke as a joke. gaskets $ < header $
2. I am planning on selling the car (see sig)

 

Manifold to head.. and many times due to a broken bolt[my 94 has the rear drivers side one broken..]
Leaks only on warm start up then goes away.. sounds almost like piston slap..
Charlie

 

it does seem to quiet a little once its warm, though it DEFINITELY sounds like an exhaust leak...

 

Broken rear manifold bolts are pretty common on LT1s. I'd look there first.

 

well, I found one of my AIR tubes was really loose. I am hoping that's what the problem was. The previous owner had douched up the threads on the fitting that goes into the manifold. So I pulled both tubes out and plugged the holes. I haven't run the car yet though, I did a few other things (free mods) too and didn't get it back together before dark.

 

take a white dry paper towel and wipe the head/manifold joint

carbon?