ls3 intake rocker failure has anyone seen anything like this before??
 

Did you send them your GM rockers to upgrade or did you just get the trunions and swap them yourself? Or buy assembled rockers from them?
1st thought is rockers weren't hardened correctly.
Hopefully you can flush all the debris out, put new rockers on, and hit the streets.

Those are chinese rockers thats why.
You can clearly tell from the enlarged hole on the valve end.

Investment cast rockers arent hardened. they are poured into a mold. Those are an inherently weak rocker because of that large hole in the casting snd break there often.

The factory ones are investment cast also yes.
They are poured into a mold that originally had a wax duplicate of it, the wax melts out and the metal fills the void that is why they have that rough texture. Then they are machined.

OE suppliers have much more rigorous QC also. Typically.

It seems with so many things LS related, OE is best, especially when it comes to sensors and highly stressed small parts LIKE rocker arms. You don't want the short end of the stick with that kind of stuff. The LS is state of the art when it comes to pushrod OHV engines. The surrounding parts MUST live up to that...

Just some more info,, I worked a consulting gig with a couple companies in CA,, while there I got to know a guy who was staying at the same hotel and worked for an engine parts, manufacturer. They had to move most of the manufacturing of their products overseas due to US regulations choking them to death.. Ane he learned a few hard lessons along the way.

In the process one of the main issues they came up with was the Asian companies that could do castings, would not police their metal supply. So one of the costs of having their billets cast and forged over there was they had to hire a bird dog to follow the metal, from the scrap processing through shipping back to the US for final machining.. They kept finding un-melted scrap like hardened bolts embedded in the billets when they tried to machine them, kept tearing up some expensive tooling.
I would bet that's part of the problem on the cast rockers.. Not enough material QC to insure consistent results of the final products.

I'd say you got EXTREMELY LUCKY that all the valves are still in the head. By the looks of the broken rocker pressing on the retainer only, the locks should have come right out and dropped a valve into the cylinder.

Yes, you get what you pay for with off-shore components. Not that ALL are bad, but there is risk with ANY component like that.

Do yourself a favor and get a set of new OEM intake and exhaust rockers, a CHE trunion kit and install them yourself. All it takes is simple hand tools and a bench vise.

Here's some more info on the CHE kit.

https://ls1tech.com/forums/generatio...nion-kits.html

Stock springs? what poundage? dual springs? seems like somethings to tight or heavy too much lift spring bottoming

From the pics you can clearly see the BTR double springs and Titanium retainers

Its the casting design of that rocker. it has a very thin area due to the large oil hole drain opening.