LSXRX7

ok i bought a lm4 = aluminum 5.3... bored it out to 3.905 and put ls6 heads on with a ms3 cam. my compression is low(compression test) so i was wondering if i need to mill the blocks deck ??? any ideas would be great thanx

LSXRX7

any suggestions

cavmattz24

iTrader: (7)

....um.... I thought that the LM4 aluminum 5.3l engines could only be bored a max of .010.

I know that the iron 5.3l engines can safely be bored to 3.905 but some still recommend getting the block sonic tested for that.

I hope I am wrong for your sake!

PETE180

iTrader: (1)

I have a book that said the cylinder liner is an LS1 99 mm liner just not bored out to the ls1 size.

It does look pretty thick on my lm4....

NemeSS

iTrader: (127)

hmmm...
makes sense, sort of
id be weary, i dont think the lm4 5.3 aluminum block was designed to
be bored to a ls1 bore size but i may be wrong