Which block Do I have
Thread Starter
Teching In
Joined: Jul 2022
Posts: 14
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Which block Do I have I recently picked up a solid NA build 05 CTS-V, it’s cammed has ported heads and bolt ons, i confirmed it has an ls6 intake and ls6 heads (243). I knew before i bought it that it does have a new shortblock and being dumb i didn’t look at the casting number. I just checked the number and it is 12559378, Looks like this is an ls1 block and not an ls6 block, I’d like anyone who can to confirm that it’s an ls1 block and are there any real differences? I’m especially interested if this block puts me in a worse position when it comes to boost as I’d like to LSA it this winter.
TLDR: is casting #12559378 an LS1 or LS6 block and if LS1 am I in a worse position to boost it and why.
TLDR: is casting #12559378 an LS1 or LS6 block and if LS1 am I in a worse position to boost it and why.
TECH Addict
Joined: Dec 2017
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Main difference is, the LS6 has "windows" in the main bearing webbing area, to aid crankcase ventilation. This adds some HP butt the tradeoff is, it slightly decreases the ultimate "strength" of the block. (emphasis on "slightly")
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Thread Starter
Teching In
Joined: Jul 2022
Posts: 14
Likes: 2
Main difference is, the LS6 has "windows" in the main bearing webbing area, to aid crankcase ventilation. This adds some HP butt the tradeoff is, it slightly decreases the ultimate "strength" of the block. (emphasis on "slightly")
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Thread Starter
Teching In
Joined: Jul 2022
Posts: 14
Likes: 2
Main difference is, the LS6 has "windows" in the main bearing webbing area, to aid crankcase ventilation. This adds some HP butt the tradeoff is, it slightly decreases the ultimate "strength" of the block. (emphasis on "slightly")
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Hard to say whether it makes any kind of difference for "boost". That word covers ALOT of ground; not exactly a one-size-fits-all deal. Not sure what the ultimate potential limit of the LSA setup is, butt I doubt it would endanger the block, FWIW. Butt if yours is the older style without the "windows" then it's at least not vulnerable in that way.
Actually I just saw someone saying that that casting number is 01 and under so that would make it not have the webbing correct?
