JoeNova

Didn't some of the 5.3 aluminum blocks have the breathing windows in them?

JakeFusion

iTrader: (7)

L33 did... but nobody sleeves those. Unless it's the MID stuff.

Che70velle

iTrader: (6)

Jay, I was searching for a manifold test over on CF and saw your N/A thread. Geesh man. Reminded me quickly why I don’t go over there much. There’s more drama over there than both of the soap operas my wife records combined! Absolutely ruined your thread.

Double06

If you are doing something like this (sleeving a GM block), is there any difference between LS2 vs LS3. I thought I read the LS3 they beefed / changed things up in a few areas?

JakeFusion

iTrader: (7)

I've always heard the LS2 block was the strongest aluminum block that wasn't the 5.3L (because of smaller bore and lack of bay windows) or LSA/LS9.

KCS

iTrader: (20)

If I remember correctly, GM revised the bay windows on the LS3 blocks. They made them bigger without reducing strength, supposedly.

Steve - Race Eng

iTrader: (1)

The Gen V 5.3 blocks are windowed. Also all of the front drive 5.3 blocks.

Steve - Race Eng

iTrader: (1)

GM put a larger radius at the bottom of the bores at the main bearing bulkhead. However, when the blocks are sleeved for a larger bore that radius has to be cut away for honing stone clearance.

Any of the blocks with breather holes can crack between the breather holes and cam bearing bores. This happens when the blocks are used for pedal to the metal racing, desert race trucks, for miles and miles. The 5.3 blocks hold up much better with the solid main bearing bulkheads.

Steve - Race Eng

iTrader: (1)

I sleeve both. As I mentioned earlier the LS3 has a larger radius at the bottom of the bores, similar to the LS7 blocks. This has to be machined away during sleeving or the block couldn't be honed after. However the poor sleeve placement from the factory makes some LS3 blocks harder to sleeve. To clean up the bores they may all have to be shifted a few thou out of position from where they should be to get down to bare aluminum. I sleeved an LSA block yesterday that cleaned up nicely but that's often not the case. On the LS2 the cast in iron liner is smaller on the outside diameter so this isn't an issue.

Steve - Race Eng

iTrader: (1)

This is one of the worst LS3 blocks I have seen. Photo was sent to me yesterday by another member of this forum. No clue how this passed inspection at GM.

G Atsma

Talk about core shift....

bortous

Great GM quality control as usual.
Toyota and Honda could learn a thing or two about this.

G Atsma

As in how NOT to do it.... lol

jayyyw

Yeah, that post turned into a **** show in no time. Before that, I hadn't posted much in that section. I remember why.