ChrisBorsheim

iTrader: (3)

I posted this on internal, but I think it's better suited here, c&p.

Just trying to gather as many specs as I can about this motor I purchased and was looking for some help.

Google hasn't really solidified my questioning.

Block Number: 12559378
Heads are 241
Intake: 12561184 (I understand this is the LS6 intake off an FBody)

I mainly curious about the year. Apparently there's enough of a different between the years to require separations for certain parts.

Thanks guys.

ChrisBorsheim

iTrader: (3)

yeah, this was supposed to go under the GEN3 forum. dang it.

uphigh07

iTrader: (48)

i have also been looking to see if my block is 04 or and older one for head studs and i cant find any answers at all. I may call the dealership to see if they would have any idea, just and idea.

j_dover

iTrader: (18)

i ran the numbers for u sorry bro its a ford 289 lol jk

squee

iTrader: (16)

12561168 denotes a LS6 block, so its a LS1 block for sure. What year isn't really possible to tell for sure, but its a 00-02. http://chevythunder.com/LS1%20components.htm

Since it has the F-body LS6 intake, its not a 00 mostlikely. Its a 01-02 LS1 block unless someone changed the intake, which in that case it could very well be a 00. Regardless, there are no differences to worry about. Everything interchanges.

uphigh07

iTrader: (48)

that website is sweet but no i know that there is no way to find out what year my block is to order the studs FML

formula17

iTrader: (4)

The head studs are not determined by the block. They go by which heads you are using. Their are only 2 diff head studs, as far as I know for an LS engine. Early engines prior to 04, Use a longer stud. After 04 they use a shorter stud. You can get the early stud in a 6 point or 12 point, But the later stud I believe only comes in 12 point.

squee

iTrader: (16)

Not true. If you look at the numbers you can determine what years it could be, thus narrowing it down. If its not a LS6 block, than its a 02 or before thus no need to order the shorter studs.

Scoggin Dickey

iTrader: (34)

That is backwards. It is determined entirely by the block regardless of what heads you use.

The early engines used a combination of long and short bolts and the 04+ use all short bolts.





To the original poster, I believe you have an older block and you would need the pre-04 head bolts or studs. If you have any questions feel free to shoot me a message or give me a call.

MillsMotorvation

Great info on that site, thanks!!