What are the differences in the 5.3L?

[jasyc240sx]

I am going to do a LSX swap into my 240SX and will probably end up with a 5.3L. I have been trolling your fourm for a while now and seen how you guys make great numbers and track times with your 5.3L's. Could someone please explain the differences in the LM7, L59, L33? Which is the best performace wise? An info or link to good info would be great.
Thanks in advance,
Joshua

[foggy]

The L33 is the aluminum block and has higher compression ratio.

[foggy]

This tells all about them.
http://media.gm.com/division/2005_prodinfo/powertrain/whats%20new/Gen%20III/2005%20Gen%20III%20Truck/2005%20L33-LM7-L59.doc

[jasyc240sx]

This tells all about them.
http://media.gm.com/division/2005_pr...33-LM7-L59.doc

Thanks that is what I needed.

[RedHeartbeat]

GM Media Online: English

Thanks for the link, Foggy. This is GM's press release site with a lot of good searchable information.

[foggy]

compression ratios
L59 9.5-1 iron block
LM7 9.5-1 iron block
L33 9.9-1 aluminum block

[ducky]

wow that really is a good read. and explains alot. especially about the TAC

[LS6 Silverado]

So am I understanding this- They say the newer L33 5.3L uses the LS6 cylinder heads. The 243 casting I presume? Wonder why they say on GM parts direct that LS6 heads will not fit the 4.8 or 5.3 due to the bore being to small. Would really like to put a milled set of 243's on my 5.3- Anyone done anything like this?

[newchevy]

hey jasyc240sx, my girlfriend drives a 95 240sx and it needs a new engine bad!!! are you planning on selling the one out of your 240 or what?

[jasyc240sx]

I would be but I am still a long way from doing this. sorry