243 and 799 heads
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ok just finished my cam and head swap finally. well i swap cam first and got the car tuned it a 99 a4 t/a with a (lq4 and 212/222 550/549 116+3 mac mid headers lid) i had 853 when i got it tune then i swap for 243/799 head.what I want to know is will the 243 throw my tune off enough for me to lose power. or should i get it tuned again to feel the gain
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Someone correct me if I wrong but I think it would be about the same with the 243 heads. But didn't the lq4 come with 317 heads and the 853 come on some of the ls1 cars?
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Isn't the lq4 9.5:1 with the 317 and if you put the 853 or 243 heads with out milling them it would lower the CR because of the combustion chambers but I may be wrong some correct me if I wrong.
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LS1 heads have bigger chambers then 243/799 heads meaning you get a bump in compression going to the better head. It roughly breaks down like this (based on memory): Higher the number, lower the compression
317 head: 72cc
LS1 head (853, 241): 67cc
LS6 head (243, 799): 64cc
5.3 head: 62cc
317 head: 72cc
LS1 head (853, 241): 67cc
LS6 head (243, 799): 64cc
5.3 head: 62cc