LSX Block Decking?

[70TWO NOVA]

I have a 5.3 im building. Im using a set of 317 heads that i got milled .030" to get the chambers to 66cc. With the stock dish pistons (which i dont want to change) this only gets me to like 9.2:1 Compression ratio. I want to squeeze a little more compression out of it and was thinking of getting the block decked a little maybe. Is this safe of an LS motor? Is it going to cause my intake not to line up with the ports at all? Never done it and wanted to get some insight.
Thanks

[jasonsnova]

might want to do some measureing...most lsx engines stock pistons stick out of the bore .005-.010 , you'd be better off getting some cometic head gaskets, stock head gaskets are .054, cometics come as thin as .030, but try to keep the quench to a minimum of .015 on a street engine.

[LSx_88_Ciera]

Just curious what is the reason you want to keep the stock dished pistons. If it is a cost issue one solution would be find a set of stock 4.8 pistons they are the same as the 5.3 other than they are flat top. The 4.8 uses a longer rod which allows the piston compression height to be the same as the 5.3.
Since you are concerned about intake alignment did the machine shop also mill the intake side of the heads for proper alignment.

[70TWO NOVA]

Just curious what is the reason you want to keep the stock dished pistons. If it is a cost issue one solution would be find a set of stock 4.8 pistons they are the same as the 5.3 other than they are flat top. The 4.8 uses a longer rod which allows the piston compression height to be the same as the 5.3.
Since you are concerned about intake alignment did the machine shop also mill the intake side of the heads for proper alignment.

I have been looking for a set of decent priced 4.8l pistons but havent come up with anything yet. Know of any good sources? I know there is not issue with intake alignment on a .030" mill cause ive done that before on another ls engine.

[LSx_88_Ciera]

Best source I know of is http://car-part.com/ and search for engine for something that the 4.8 came in and then go to the page that has an asterisk next to it, look for a core motor and get on the phone to see what the deal is. Depending on what is good you could end up getting the pistons for free.

[70TWO NOVA]

thanks that is a good resource for sure. I appreciate the help

[CarlC]

0.015"? That's pretty thin.

[SatisTraction]

why not get some ls1 pistons and bore it to a 5.7l.

[LSx_88_Ciera]

0.015"? That's pretty thin.

Agreed especially since most everything I have ever read says that .037 is the ideal quench, I have been out of performance for a few years though so opinions may have changed

[SatisTraction]

there is a set of ls1 pistons in the classifieds.