m.lion

newbie here, i want to build a aluminum 427. I was thinking of using one of these blocks and have it sleeved accordingly. I have ls3 cylinder heads and edelbrock carb intake. Is this my options other than buying a ls7 block or a aftermarket piece? if anyone has done this please chime in, Im eager to learn what makes big numbers. this is a race application no street stuff here

litle88

iTrader: (20)

You can send either of those blocks to ERL to get resleaved. Or stroke the Ls3 to a 427 and get the appropriate piston for your application if you plan on a Lil dope or boost.

If I wanted a block resleaved by ERL I'd get a junkyard aluminum 5.3 and send it to them.

Steve - Race Eng

iTrader: (1)

The LS2 block is generally the best of the blocks to sleeve. LS3 has factory sleeve mis alignment issues that sometimes interfere with correct placement of the new liners.

The 5.3 aluminum truck blocks and rarer 6L are the strongest of the factory blocks due to their solid main bearing bulkheads. You have to be careful with the 5.3 blocks as some are actually Gen III castings internally - no siamesed bores. You need a block with siamesed bores for dry sleeving.

On the 5.3 blocks, as an option, I drill a breather hole through the block just like the earlier LS1 blocks. This helps with the lack of bay to bay breathing lacking in these castings.

Darton Seal Tight dry liners have a max. bore of 4.185" so you can build a 440" engine with 4" stroke or step up to a 454" with 4.125" stroke. You may however need more head than you have with the larger engines.

I have one of my LS2 dry sleeved blocks holding over 1,200 hp in an HK Enterprises built engine. Another of Erik's customers recently ran 203mph in the Texas Mile. Fastest LS aluminum stock block - stock head speed ever run there.

Steve

litle88

iTrader: (20)

Good info Steve thanks!!!

m.lion

thanks guys! Is there any significant markings or a certain year of 5.3 that is a for sure block to do this with?

86Z28USAF

iTrader: (1)

i dont think there is really they were in the early 2000 yukons and tahoes. you can also boost those beasts as is