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Ford Motor Co. Vacuum Advance & Retard Specifications

NOTE: FOR ENGINE RPM AND DEGREES. MULTIPLY SPECIFICATIONS BELOW BY 2
Distributor Part No. (1) Vacuum Advance (Distr. Degrees) Vacuum Retard (Distr. Degrees)
Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg. Deg. In. Hg.
C8AF-B 0-1 5 3-6 10 6 1/2-8 15 6 1/2-9 20 6 1/2-9 25 0-2 1/4 5 4-6 10 5-7 15 5-7 20
C8VF-C 0-3/4 5 1/2-4 10 6-9 15 8 1/2-11 1/2 20 9 1/2-12 25 0-1/2 5 1-5 1/4 10 5-7 15 5-7 20
C9DF-B 0-3/4 5 1 1/4-4 3/4 10 5 1/2-8 15 5 1/2-8 20 5 1/2-8 25 0-2 5 3/4-6 10 5-7 15 5-7 20
DOAF-AE 0-1 1/2 5 0-2 1/2 10 0-2 1/2 15 0-2 1/2 20 0-2 1/2 25 0-1 5 2 1/2-7 10 5-7 15 5-7 20
DOAF-Y 0-3/4 5 0-2 1/4 10 3 3/4-6 3/4 15 7 1/4-10 1/4 20 8 1/2-11 25 0-1/2 5 1 3/4-6 10 5-7 15 5-7 20
DOAF-Z 0-3/4 5 0-1 3/4 10 3-6 15 6 3/4-9 3/4 20 8 1/2-11 25                
DODF-C 0-1 5 4-7 10 4 1/2-7 15 4 1/2-7 20 4 1/2-7 25 0-1/4 5 1 1/2-6 10 5-7 15 5-7 20
DOOF-A                                    
DOOF-AA 0-1 1/4 5 3-6 10 6-8 1/2 15 6-8 1/2 20 6-8 1/2 25 0-2 5 2 3/4-6 to 5-7 15 5-7 20
DOOF-AC 0-1 5 2 1/2-5 10 2 1/2-5 15 2 1/2-5 20 2 1/2-5 25 0-1 5 2-7 10 5-7 15 5-7 20
DOOF-G 0-1 5 1-4 1/2 10 5 1/2-8 1/2 15 8-10 1/2 20 8-10 1/2 25 0 5 1-7 10 5-7 15 5-7 20
DOOF-T 0-2 5 5-8 10 9-12 15 10-12 1/2 20 10-12 1/2 25 0-1/2 5 1 1/2-6 10 5-7 15 5-7 20
DOOF-U 0-1 5 2-5 1/4 10 6 1/2-9 3/4 15 9 1/2-12 1/2 20 10-12 1/2 25                
DOOF-V 0-1 5 1-4 1/2 10 5 1/2-8 1/2 15 8-10 1/2 20 8-10 1/2 25 0 5 1-7 10 5-7 15 5-7 20
DIAF-CA 0-1 5 0-1 3/4 10 4-7 15 5 1/2-8 20 5 1/2-8 25 0 5 1-7 10 5-7 15 5-7 20
DIAF-GA 0-1/2 5 0-1 1/2 10 1 1/2-4 1/2 15 4 1/2-7 20 4 1/2-7 25 0-1 5 2-7 10 5-7 15 5-7 20
DIAF-HA 0- 1/2 5 0-1 1/2 10 4 1/2-7 1/2 15 7-9 1/2 20 7-9 1/2 25 0 5 1-6 10 5-7 15 5-7 20
DIAF-KB 0-1/2 5 0-1 1/2 10 4 1/2-7 1/2 15 7-9 1/2 20 7-9 1/2 25 0 5 1-5 1/2 10 5-7 15 5-7 20
DIAF-LB 0-2 5 6 1/2-9 10 6 1/2-9 15 6 1/2-9 20 6 1/2-9 25 0-1/2 5 2-4 10 2-4 15 2-4 20
DIAF-NA 0-1 5 0-4 10 5-8 1/2 15 6-8 1/2 20 6-8 1/2 25 0-5 5 5-7 10 5-7 15 5-7 20
DIDF-BA                                    
DIDF-BB 0-1 5 1-4 10 5-7 1/2 15 5-7 1/2 20 5-7 1/2 25 0-1 1/2 5 2 1/2-7 10 5-7 15 5-7 20
DIDF-CA                                    
DIDF-EA 0-1 1/2 5 3 1/2-6 1/2 10 7 1/2-11 1/2 15 9-11 1/2 20 9-11 1/2 25 0-1 5 2 1/2-7 10 5-7 15 5-7 20
DIDF-FA 0-3/4 5 0-3 10 5 1/2-8 15 5 1/2-8 20 5 1/2-8 25 0-5 5 5-7 10 5-7 15 5-7 20
DIDF-GA 0-1 6 0-3 10 2 1/4-5 1/4 12 4 1/2-7 14 1/2         5-7 11 1/2        
DIFZ-A 2 5 5 1/2--7 1/2 10 5 1/2-7 1/2 15 5 1/2-7 1/2 20 5 1/2-7 1/2 25 0 5 1 10 2-4 15 2-4 20
DIFZ-B 0-2 1/2 5 5-8 10 5-8 15 5-8 20 5-8 25 0 5 0-2 10 3 1/4-7 15 5-7 20
DIFZ-C 0 5 2-5 10 7-10 15 8-10 20 8-10 25 0 5 2-3 10 2-4 15 2-4 20
DIMF-AB 0-3/4 5 3/4-4 10 6-9 15 8 1/2-11 1/2 20 9 1/2-12 25 0-1 1/2 5 2-4 10 2-4 15 2-4 20
DIMF-BA 0-1 5 1/2-3 1/2 10 5-8 15 8 1/2-10 20 8 1/2-10 25 0-1 5 2-4 10 2-4 15 2-4 20
DIMF-FA 0-3/4 5 0-1 3/4 10 2 1/4-5 1/4 15 6-9 20 8 1/2-11 25 0-1 1/2 5 2 1/4-6 10 5-7 15 5-7 20
DIOF-AA                                    
DIOF-AB 0-1 5 2-5 10 5-7 1/2 15 5-7 1/2 20 5-7 1/2 25                
DIOF-BA                                    
DIOF-BB 0-1 5 1/2-3 1/2 10 5-7 1/2 15 5-7 1/2 20 5-7 1/2 25                
DIOF-CA 0-1 5 4---7 10 7 1/2-10 15 7 1/2-10 20 7 1/2-10 25 0-2 5 3-7 10 5-7 15 5-7 20
DIOF-GA 0-1 5 0-2 10 3-6 15 6 1/2-9 1/2 20 8 1/2-11 25 0-2 1/2 5 2-4 10 2-4 15 2-4 20
DIOF-LA 0-1 5 1-4 1/2 10 5-7 15 7-10 1/2 20 7-10 1/2 25 0 5 1-7 10 5-7 15 5-7 20
DISF-BA 0-3/4 5 0-1 3/4 10 2-5 1/4 15 6-9 20 8 1/2-11 25                
DIVF-AA 0-3/4 5 0-2 10 3-6 15 5 1/2-8 1/2 20 6-8 1/2 25                
DIZF-AA 0-1/2 5 0-1/4 10 0-2 15 0-2 1/2 20 0-2 1/2 25 0-6 5 5-7 10 5-7 15 5-7 20
(1) Part No. prefix and suffix stamped on housing. Basic Ford Part No. (omitted) is "12127".