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V6Sprout
11-22-2002, 12:28 PM
whats the stock compression ratio on teh SC's? I forget but I think it was 8.5:1 correct?
WayneI
11-22-2002, 02:07 PM
8.2:1
V6Sprout
11-22-2002, 02:57 PM
ahh ok, thanks Wayne.
Bill McNeil
11-23-2002, 03:51 AM
The early and late model SC engines had different compression ratios. I thought it was 8.5:1 also.
SeanMatteson
11-23-2002, 09:40 AM
I'm with Bill. I thought the nominal CR on these things was 8.5:1, and that his CR was lowered to 8.3:1 due to the other mods that he has put on the motor. I think the assisted CR (blower making boost) is somewhere in the neighbourhood of 11.5:1 at peak.

Maybe Ed has some literature from Ford that might clear this up for us.

Cheers,

Sean
Bill McNeil
11-23-2002, 11:02 AM
The 8.5:1 is information I got from both Tom and Fred.

Wayne is right about one of the versions, because I recognize that number as being spec for either the early or late model engines. I read it somewhere recently that I can't recall.

Mine is 8.3:1 anyway, and when you add boost, Sean is right too.
Paul93SC
11-23-2002, 11:41 AM
89-93 engines are 8.2:1
94-95 engines are 8.5:1

Now, as a rule-of-thumb the compression ratio rises by 1 for every 3.7 lbs of boost.