Will LS4 243 heads fit a 2000-2001 LS1 block?
#1
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Pretty much what the title says. I was wondering if LS4 243s from a 2007 will bolt directly onto a 2000 LS1 block. I bought an LS4 for a project and i am planing on having the 243s sent out to be ported for my 68 firebird, and putting the 241s back on the LS4 since this project wont need the extra power. Will this worrk?
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Well i was just curious becase ive been reading about different head changes from the 2004 model and up they sell different head bolt kits. Ive also read something about the 6 bolts heads and such and i wasnt really sure. I'll know as soon as i pick up the engine tomorrow but i was just doing some reasearch in the meantime.
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243 are ls6 heads.
"243" cast into this head signifies it is an LS6 head cast made between '01-'04
#243 aluminum cylinder head is used on the 2001 - 2004 Corvette ZO6, Cadillac CTS-V and the new 2005-2007 LS2 powered C6 Corvette, 2005-2006 GTO & SSR
"243" cast into this head signifies it is an LS6 head cast made between '01-'04
#243 aluminum cylinder head is used on the 2001 - 2004 Corvette ZO6, Cadillac CTS-V and the new 2005-2007 LS2 powered C6 Corvette, 2005-2006 GTO & SSR
#5
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Great! thank you. I knew they were ls6 heads but was just curious if they were different. I know they dont have have sodium filled valves the LS6 has. Was wondering if there were any other changes. From what ive read they use LS1 springs though right? Not the ls6 springs.
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You might want to investigate valve sizing. I believe that the 243 heads used on the 5.3's and 4.8's have smaller valves due to cylinder shrouding problems on the smaller bore.
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