408ci build, expectations/suggestion.......
#21
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with that combo and an M6, i would be more worried about the 12bolt. if you didnt already buy it i would consider a 9" over the 12 bolt. the 6 speeds in cammed LS1's are known for breaking 12 bolts. i would not want one behind a head and cammed 408 going through a 6 speed. but that is just my opinion.
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I'm doing a similar conversion going from a 370 to a 408. I have the tfs 215, but wonder is that the best head for a 408. I also have the Fast 102, etc and 1 17/8 headers. What are your opinions on these heads.
#23
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with that combo and an M6, i would be more worried about the 12bolt. if you didnt already buy it i would consider a 9" over the 12 bolt. the 6 speeds in cammed LS1's are known for breaking 12 bolts. i would not want one behind a head and cammed 408 going through a 6 speed. but that is just my opinion.
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The only other question that I have is wat type of spark plugs to use of should say how hot to use. I'll post the dyno sheet on this thread to show what it makes! Thank you again
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My Personal H/C/I Z06 is at 92-95KPA, Friends FAST 102, 100mm MAF, FTP 104 Lid, PRC 227 heads, VX.4 Cam LS1 is at 92-94KPA. When my GTO was Magnuson blower only it was 98 to 100KPA!