V-6 head casting numbers help

[fastback4]

Here is the casting numbers from a set of v-6 heads i have. How much information can you get from this?

10218170 with rollers......Tom

[SappySE107]

how much information do you need?

[fastback4]

size of engine, year, model GM vehical......Tom

[pocket-rocket]

I believe all you are going to get is the engine size (unless it falls in the years the 3100 and 3400 used the same heads) and year range. They don't change part numbers for each year and vehicle model.

[SappySE107]

Its for large port 3100 and 3400 engines. Not the latest casting but still good. 10mm rockers only. 487 castings are newer and can be 10 or 8mm rockers.

[fastback4]

V-6 head casting numbers

Its for large port 3100 and 3400 engines. Not the latest casting but still good. 10mm rockers only. 487 castings are newer and can be 10 or 8mm rockers.

What does the 8 or 10mm mean? Never heard this mentioned here at 60deg. before

[bszopi]

In ~2004, GM went to 8mm studs for the rocker arms. Prior to that, they were 10mm studs. 8mm, IIRC, is what the LSx engines use, so it was a shift to limit the number of different parts and whatnot between various engine families.

[SappySE107]

02 is the transition year. All 03+ are 8mm, 02 can be either.

[Superdave]

1996-1999 3400 V6 and 00-01 3100 V6

It is interchangeable with the 487 heads (24507487)