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In a message dated 10/22/13 21 44 14, MikeLDrew@aol.com writes:<BR>
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>>>I believe the early cars came with 21mm master cylinders, and the GT5-S was 23mm. <BR>
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>>>Disregard all that. I was getting my sizes mixed up between clutch and BRAKE master cylinders. The numbers above are for the brake master cylinders.<BR>
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I think the clutch master is almost exactly what you need it to be. Rather than baffle you with another dimly remembered BS answer, I went into one of my spare parts rooms and waded into a box of old, junk parts that are kept strictly as conversation pieces. I got an old factory clutch master cylinder and took it apart and got after it with the dial calipers.<BR>
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The piston measures .7455 inches or thereabouts, close enough to .75 inches to safely call it 3/4 inch. :>)<BR>
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Mike</FONT><FONT COLOR="#000000" FACE="Geneva" FAMILY="SANSSERIF" SIZE="2"></FONT></HTML>