snkeh8tr

Whats the story with these? What motor are they stock for? Why are people putting them on LS1's? Do they lower compression ratio? whats the internal numbers on these heads?

I am totally confused about why these heads benefit these engines.
Any help is appreciated.

Taspeed

iTrader: (1)

They are from a 5.3L Gen III engine. they come in cars from GTP's to trucks. They have smaller combustion chambers and raise the compression about 1/2 a point. Internal # are the same as regular LS1 heads except the intake valve is 1.88 or something and the ls1 has a 2.0 intake valve. There is a thread somewhere that depicts all of the different head castings and the differences in them.....search is your friend, and will likely keep people from beating you down

conan

iTrader: (5)

The 5.3L head has a smaller combustion chamber (CC) than the 5.7L head the smaller CC increases compression ratio thus increasing HP. Puting a 6.0L head on a 5.7L block does the oposite decreases compression ratio.

snkeh8tr

thanks man.

Taspeed

iTrader: (1)

exactly...no problem.