6literc10

was looking into boring the cast iron 5.3 to a 5.7 bore but was concerned about 2 things. one, boring out this far does it make the sleeves too weak? two, is there a hardening surface that gets lost boring out that far?

gagliano7

Thompson motorsports does this all the time so i am sure you will be fine. They also do it with the 5.3 aluminum blocks.

thompson

iTrader: (4)

It works but it must be done by someone who has done many of them before. You need to see where the cylinders are more thin and bore accordingly. If done properly you should have no problems.
Thank you,
Kyle
Thompson Motorsports

Tuskyz28

I have seen a 3.902 bore on a LM7 iron block....

Burken01

iTrader: (88)

My turbo build in my Sig below I did the same thing your asking.. Punched a 5.3 out to 5.7 so I could reuse my rotating assembly from the previous engine..

It worked great!! Don't skimp out on who you get to do the work..

ATK Engines

iTrader: (1)

No big deal, we will be offering these bare blocks for sale very soon in a 3.903 bore.