Serious Concerns Over Parts Availability

[XfireZ51]

Where did u find liners and rings? Was it recent?

[tnova]

Jerry’s of course. About two years ago. Liners were no problem but I think I bought the last complete set of rings that he had. At the time I was rebuilding the engine with passing CA smog in mind. I no longer live in SoCal so I should have gone with the kit he now sells that use aftermarket pistons, rings, and rods. Heads, IP, IH, and TB are ported by GVD.


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[gtcollins@maxnet.co.nz]

That's what happened to my LT5 left hand catalytic converter collapsed and destroyed the liners cat material was all the way over on the right hand side no damage to the liners on the thought but the left were totally worn away my car is 1990 0308 with 24000 miles on it some said it was early 1990s that have that problem a friend has just just brought 1990 0549 the catalytic converters were checked before he purchased the ZR-1 all ok my ZR-1 always had white streaks or a grayish appearance in the left exhaust were the other side was always black when the catalytic converter failed the exhaust was totally white so maybe if you so now knowing about the catalytic converter problem if I see a ZR-1 with the same symptoms it's not a big job to remove the 02 sensors and check the catalytic converter material it should be white looking and flat across the surface with no pitting

Glen


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[KJL]

Just out of curiosity did you do the engine work yourself? I know it takes some special tools and know-how to to work on these things.
Did you put new converters on or just delete them?

[A26B]

Here is what catalytic dust does to the LT5 oil control ring.

https://www.jerrysgaskets.com/cataly...mage-to-rings/

The damage to the Oil Control Ring occurs AFTER the catalytic dust has gone past both compression rings.

[KJL]

Originally Posted by A26B

Here is what catalytic dust does to the LT5 oil control ring.

https://www.jerrysgaskets.com/cataly...mage-to-rings/

The damage to the Oil Control Ring occurs AFTER the catalytic dust has gone past both compression rings.

What is the solution? I have a 1992 with original cats with only 25000 miles on it. My 95 has new aftermarket cats and headers.

[EvanZR1]

Originally Posted by KJL

What is the solution?

Long tubes with no cats?

[A26B]

Exhaust design change in 93 incorporated moving the catalytic converters further away towards the rear, along with making the converter separate instead of integral with the exhaust header.

FOR THE MOST ORIGINAL APPEARING MODIFICATION
There are several different things that can be done. I would recommend removing the manifold/cat assembly and gut the cats. Then if necessary, install a metallic substrate catalytic converter behind the original.

[gtcollins@maxnet.co.nz]

Originally Posted by KJL

What is the solution? I have a 1992 with original cats with only 25000 miles on it. My 95 has new aftermarket cats and headers.

This is my solution and I got a second engine for my ZR-1 and will be rebuilding the original I bought tools and will make some as well

Glen Collins 20170814_105141_001.jpg

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[tnova]

I did the rebuild myself. I've rebuilt several engines transmissions over the years and didn't find the LT5 that unique conceptually to work on. The FMS engine manual and Net have oodles of information on procedures and tips to work specifically on the LT5. As for special tools I have a hodge-podge of self made, adapted, and purchased from others (Phil) except for the cam retainers which I borrowed. Now Marc has drawings of the cam retainers to have machined and even easier, Jerry sells complete sets. Jerry also has drawings of simple tools on his site. Only problem i had was the tool to set the pilot bearing depth but adapted and measured for that. Discovered that the crankshaft turning socket used during assembly is very close to one on the self at local autoparts store for a Chrysler.

Regarding cats, I had an initial plan since I still lived in SoCal to replace the manifolds with cats with a low mileage set I bought from Marc which are still on a shelf in my home shop. Once I moved I put on a set of headers and was going go install them with a set of C6 cats. But now I have no smog requirement so the headers go directly into an X-pipe that replaced the first sound damper (muffler? resonator?). I'm holding onto the C6 cats incase I ever have to get it smogged again and will have them integrated in the header to X-pipe tubing.

If you must have the original exhaust manifolds in your state, I'd gut the cats if they're failing and run it that way. I'm in support of reasonable requirements to reduce pollution, especially since more efficient engines with little pollution are really just engines ringing out HP and torque as never before. Modern engines with computer controls and high flow intakes and exhausts, including cats, really make better performance that our smogged choked engines of the 70's, 80's, and 90's. Happy to move my LT5 forward a decade or so.