SS comes with a flex pipe. Hard to see it, on the left.

 

It’s just not the accordion flex pipe like the 2.2 or 2.4 has.

 

In the picture above that flex joint is called a bellows.
The one that looks like a "Chinese finger" is a flex coupling.
Yes the bellows style is more prone to crack than the other one.

 

These are not from an SS , Left one is a flex , right one is a bellows I believe the SS came with the flex and not a bellows

 

Yes, SS is like the one on the left.

 

Actually that’s the one from my 2.2 with the mandrel bends. But I know what you mean the Chinese finger mesh looking one.

 

Are all codes always logged so that I can check them in the garage and not while driving?
do they stay after engine shutoff or need to keep engine running?

i have a trifecta cable and my laptop that I think can read codes.
will have a look Today after a drive now my headliner is back up.

 

It's been a while, such is covid life.

My mechanic says it isn't an exhaust leak.
They tried to scope to see the valves, and his scope got so gunked up he couldn't see anything! So lots of gnarly intake cleaner later, he reports the valves do have a fair amount of carbon on them, but not clear that's the full problem.
Now they have finally found some metal in the oil, so something is definitely degrading, still no codes though so hopefully nothing is too far gone, but it does make it harder to figure out what.
He thinks most likely metal would be from timing chain/sprockets/guides wearing.

He's now recommending pull the head and send it over to the machinist to test for proper operation of all the valves and springs and things, give it a good cleaning, meanwhile they clean the intake really well, and look over all the timing side, replace all that while they're in there.
With labor and parts (very rough estimate, since only assuming what parts) quoting about $2000.
He feels that if they get in there and find some scoring somewhere that indicates it would be a much bigger repair, they can still put it all back together and it will run as well as it does (vibrations and noise some people may just say, "old car", but I'd probably get rid of it).

Any special info on parts or things to look for I should pass along?
It looks like Cloyes makes claims that their timing chain kits have some "improvement" parts over OEM (balance shaft sprokets, latest tensioner) - is that the recommended path?
Anything particularly special about these heads the machinist should know?

 

In all this, you don't say if a compression test or leak down test has been performed. All that gunk, oldblue's very first suggestion is looking correct. Gunk on the intake valves, causing poor compression. It cannot be cleaned simply. Your choices are to remove the head and have it cleaned, or to blast the valves with the intake manifold removed, with walnut shell media. Here is the how-to, there's a link in the how-to for a variation.

I would do the compression test, and then a leak down test.

https://www.chevyhhr.net/forums/www....ad.php?t=56184

 

I’d suggest the Cloyes 9-4201SAWP kit, pull the head and have it cleaned , all the carbon cleaner can damage the catalytic converters. If you’re handsome but not handy, pay the mechanic to do this , if you’re handy , and have some mechanical experience, do the work yourself.

https://www.rockauto.com/en/parts/cl...iming+set,5756

Note, you won’t need the cam phasers or balance shaft gears , the 2.0 crankshaft sprocket is different so reuse the original one. Unless the part number stamped in the sprockets match.