StrokerLS1

iTrader: (14)

I found some 0821 casting heads for fairly cheap. Are these the same as L92 heads? Are they the heads that came off a LS3? Im looking to put them on my 408ci. Thanks

69LT1Bird

iTrader: (1)

821 is from the LS3. L92 and LS3 have the same port shape and combustion chamber sizes. The 821 should have the lighter valves. Originally GM used a different casting process for the Corvette heads which produced smoother ports.

StrokerLS1

iTrader: (14)

Cool so these should be exactly what im looking for. Thanks. It looks like they came with yellow valve springs like the ones that came off the c5 z06. I wonder if they are the same ones

69LT1Bird

iTrader: (1)

I think they are.

Scoggin Dickey

iTrader: (34)

They are what you are looking for, they are L92 heads. Casting number doesn't necessarily indicate what valves are in a new head though. I currently have L92 castings on sale CHEAP for $630 for a set of complete heads.

Jesse

StrokerLS1

iTrader: (14)

if the ones im looking at fall through then im giving you a call. thats cheap! what is the most that can be milled off these heads. my 408 has -28cc pistons in it. i had a blower installed but sold it. im just trying to get as much compression and power out of it without changing the pistons. Thanks

1CAMWNDR

iTrader: (21)

The L92 has a 70-71cc combustion chamber. You would need to mill quite a bit to recover compression from a -28cc dish.

StrokerLS1

iTrader: (14)

yeah i know it is going to need to be quite a bit of milling. i just dont want to mill so much to where i compromise the head strengh. im guessing somewhere around .045 .050 with .042in head gaskets? i know it wont get me stock comp but hopefully somewhere around 9.5-10.0 i would hope.

Tigman

iTrader: (3)

How do they rate compared to the famed 823's?

Scoggin Dickey

iTrader: (34)

Ok, actually casting number can tell you which head it was originally on a stock head. 821s were LS3, the difference between the casting numbers is the valve seat between LS3 and L92. You're not going to have a performance or flow difference based on the casting number, it really is not relevant

patdown

So if the 0821 heads have the yellowish springs and a shiny intake valve, is that an L92 or LS3 head?

SweetS10V8

iTrader: (4)

The difference between an L92 and LS3 head are the valves and springs. The valves are what really matter because you have to match your springs to your cam anyways...

https://ls1tech.com/forums/generatio...omparison.html

Which valve is in the heads your looking at?

Scoggin Dickey

iTrader: (34)

Hey, is this Pat Downey? Glad to see you received your heads. I'm going to send you a pm.

You've got LS3 heads.

-Jesse

patdown

That's me, Jesse. Thanks for clarifying which heads I received. These heads obviously have the valve on the right in SweetSV10V8's link.

I got the long end of the stick for a change.

dmc1400

maybe a dumb question but..... will 821 heads fit a 2000 ls1? any performance increase from that? if they do fit is it a straight up bolt on deal?


thanks in advance
dave,

litle88

iTrader: (20)

Lol noob bringing it from the 3yr old death, no sir you CANNOT use Ls3/L92/L99 heads on an Ls1 because you need a minimum bore size of 4.0 in.

bww3588

iTrader: (49)

Easy asshat...at least he didn't start a new thread.

litle88

iTrader: (20)

Lol YOU CLOWN! Hows it coming bud?