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-   -   L92 Casting #'s - what's the diff? (https://ls1tech.com/forums/conversions-swaps/1375681-l92-casting-s-whats-diff.html)

cdig Jan 19, 2011 02:40 PM
L92 Casting #'s - what's the diff?
 
I'm looking at a couple different sets of L92 heads to put on a LQ4 6.0L, just wondering what the difference might be between the casting #'s ? ie. casting # 823 vs. 821 ? Is there a physical or performance difference? Is there a casting I should stay away from for any reason?

Thanks!

Project GatTagO Jan 19, 2011 08:56 PM
Originally Posted by cdig (Post 14383638)
I'm looking at a couple different sets of L92 heads to put on a LQ4 6.0L, just wondering what the difference might be between the casting #'s ? ie. casting # 823 vs. 821 ? Is there a physical or performance difference? Is there a casting I should stay away from for any reason?

Thanks!
I believe that functionally they are all the same.

Andrew

rsz288 Jan 20, 2011 09:02 AM
Originally Posted by cdig (Post 14383638)
I'm looking at a couple different sets of L92 heads to put on a LQ4 6.0L, just wondering what the difference might be between the casting #'s ? ie. casting # 823 vs. 821 ? Is there a physical or performance difference? Is there a casting I should stay away from for any reason?

Thanks!
They are all good. Later heads went to rotocasting method.

bozzhawg Jan 20, 2011 11:33 AM
Originally Posted by cdig (Post 14383638)
I'm looking at a couple different sets of L92 heads to put on a LQ4 6.0L, just wondering what the difference might be between the casting #'s ? ie. casting # 823 vs. 821 ? Is there a physical or performance difference? Is there a casting I should stay away from for any reason?

Thanks!
821= LS3/ Hollow stem intake valve/ yellow beehive springs

823= L92/ Steel intake valve/ stock springs..

Some say the 821's have a smoother finish....

reality both are the same castings, and both had some not so smooth areas but in different locations.... Nothing crazy.... I did not even touch em(port em or polish em), I just popped em on... besides milling and spring kit....

Bozz

Jimbo1367 Jan 20, 2011 04:49 PM
5364 IIRC from my 08 LY6

tsnow678 Jan 20, 2011 09:23 PM
Is it #5364? I was thinking it was #3564. Either way the difference between these and the #823 are the #5364 were cast in green sand and have a smoother finish in the ports and combustion chambers. SLP grabs all of these smoother heads from production. I tried to get a set when I bought my #823's but they looked at me like I was stupid.


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