Getting LS6 blocks yes,
Getting LS6 engines NO.

RPO coded & spec'd per GM as LS1 engines. Those engines are LS1 engine's using an LS6 block.

All LS powered fbody from GM had RPO codes for LS1 and therefore had LS1 engines. In 2001 & 2002 some of those LS1's used an LS6 block. The fbody cars with factory LS6 blocks had 241 heads. GM spec'd those motors as LS1 engines (heads etc) and RPO coded them as LS1 engines despite having an LS6 block.

Simple way to think of it - if it had 241 heads it's not an LS6 engine from the GM its an LS1 engine.

FWIW after all of that - If tomorrow I slap a set of LS6 heads (243 heads with LS6 sodium filled valves) & an LS6 cam into my LS1(RPO code LS1) 263,000 mile 2002 Z28 that came from GM with LS6 block, LS6 rods bolts etc for all practical purposes it's now a "defacto LS6 motored" car.

 

Sorry, I understood we were purely talking LS1 vs LS6 blocks. I just shortened it as I thought we all understood that. So, after LS1 or LS6, I should have typed block each time to avoid confusion.

​​​​​ I just wanted to know how they allocated the engines with the LS6 blocks on the Camaro etc, if the LS1 blocks were also still in the mix The other poster then indicated ALL Camaro blocks after a certain date were LS6?

Corvette was only car to get the actual LS6 engine, right? As I said above, we in Australia never got it. Acknowledging that an LS1 with an LS6 block and manifold is still an LS1. Which is what I think was catching out the OP.
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What ever makes you happy.

Just spelled it out in detail to help ensure you didn't have the issue confused or make it the issue extra confusing for others that might see the thread later.

The 2004-2005 Cadillac CTSV also got the LS6 engine and of course the C5Z06 2001-2004.

No idea how GM determined the mix of LS1 & LS6 blocks that ended up in fbody's.

Probably last block in was first block out. One can definitely see why the LS1 block was discontinued due to duplicate effort etc.

 

Ok, basically random it seems.

Ah, ok, the CTS-V was also an LS6 in those years. Cadillac doesn't get a lot of air time in Aus, unlike the Corvette.

Interestingly, HSV here wanted the LS6 for their top dog GTS back in 2000, however it couldn't happen. So, for their 400 HP (300 kw) LS1, they used Callaway to whip up a Heads and Cam setup to meet their requirements. It also had a bigger TB and I think it was still the only Mafless factory/ mass produced LS ever made. Engine was designated the C4B.

Unfortunately, the valve springs go bad in these and many of them have been lost. There was not many made, it was nearly exclusively used in the limited edition HSV GTS sedan and coupe.

 

Back in that era, GM made a lot of bad decisions. In 1999, I wanted a V8 Holden far more than I wanted a V8 fbody...lol.

Sounds like folks in Australia wanted the LS6. GM alwaya found ways to disappoint loyal customers everywhere in 1999-2002.

 

Ha! I did want an LS6 engine back in those days. I sort of ended up buying one with my 2004 Monaro. I thought of importing and installing proper LS6 243 along with my LS6 style baby cam, to basically make an "LS6" but my reading on here made me change my mind about utilising the sodium filled valve 243 heads. I instead just had my 241s ported.

With my reading on the Pontiac GTO, I assumed that the majority of US car fans hate Holden's.

 

Old schoolers hated the GTO because it was a badge engineered Monaro, it didn't look like what a GTO should have looked like ( according to them ). However, people who actually own and drive them seem to love them. Me, I dig all Holdens and even like some of the odd looking Aussie Fords and Chryslers. Like, it's amazing how different an Aussie Charger looks!