Owners manual

STEP 13. Inspect your flexplate. Check
for distortion, excessive warpage or
worn/elongated stud holes. (See Fig.
4) The flexplate should not be “dished”
backwards. Check condition of starter
ring gear teeth. Distorted or worn
flexplates should be replaced.
STEP 14. Check the bolt pattern of
your B&M torque converter and make
sure it matches your flexplate. There
are several bolt patterns possible from
Ford Motor Company:
C-4: (4) 3/8" studs on 11.40" B.C.
(4) 3/8" studs on 10.50" B.C.
(4) 3/8" studs on 9.28" B.C.
C-6: (4) 3/8" studs on 11.40" B.C.
(4) 3/8" studs on 9.28" B.C.
FMX: (4) 3/8" studs on 11.40" B.C.
(4) 3/8" studs on 10.50" B.C.
(4) 3/8" studs on 9.28" B.C.
AOD: (4) 3/8" studs on 11.40" B.C.
If your flexplate does not match up
to the bolt pattern on your B&M torque
converter, you will have to replace your
flexplate. You may enlarge your origi-
nal flexplate holes to accept larger 7/
16"-20 studs used on most B&M Per-
formance coverters. Use a 15/32" (.468")
dia. drill and deburr the holes after
drilling.
B&M Converter Applications
Converter B&M B&M Converter Flexplate
Part Number Converter Bolt Pattern Modifications
40425 C-6 Traveler 3/8"-24 x 11.40" B.C. Stock flexplate
40412 C-6 Holeshot 2400 7/16"-20 x 11.40" B.C. Drill 15/32"
40422 C-6 Holeshot 2400 7/16"-20 x 11.40" B.C. Drill 15/32"
40442 C-6 Holeshot 3000 7/16"-20 x 11.40" B.C. Drill 15/32"
40427 C-6 TorkMaster 2000 7/16"-20 x 11.40" B.C. Stock flexplate
50412 C-4 Holeshot 2400 3/8"-24 x 10.50" B.C. Stock flexplate
50416 C-4 Holeshot 2400 3/8"-24 x 10.50" B.C. Stock flexplate
50432 C-4 Holeshot 3000 7/16"-20 x 10.50" B.C. Drill 15/32"
50436 C-4 Holeshot 3000 7/16"-20 x 10.50" B.C. Drill 15/32"
50440 C-4 TorkMaster 2000 3/8"-24 x 10.50" B.C. Stock flexplate
40430 AOD Holeshot 2400 7/16"-20 x 11.40" B.C. Drill 15/32"
40431 AOD Holeshot 3000 7/16"-20 x 11.40" B.C. Drill 15/32"
40437 AOD TorkMaster 2000 3/8"-24 x 11.40" B.C. Stock flexplate
Note: B&M AOD 40430 & 40431 Open Converters (non-split path) do not
require any transmission modifications.
Refer to the following chart for flexplate and starter nose-piece cross reference.
Stock Flexplate Replacement Starter Nosepiece
Flexplate
C-4 Applications
C5AZ-6375-T Do not change Use same starter
11.40" bolt circle nosepiece
164 tooth ring gear
D5ZZ-6375-A C3AZ-6375-L D1AZ-11130-A
9.28" bolt circle 10.50" bolt circle
141 tooth ring gear 157 tooth ring gear
C-6 Applications
D1ZZ-6375-C D1ZZ-6375-A Use same starter
9.28" bolt circle 11.40" bolt circle nosepiece
164 tooth ring gear 164 tooth ring gear
AOD Applications
Use same flexplate
Factory part numbers are for reference only, and are not guaranteed for
accuracy.
Make sure that the replacement flexplate has an equivalent balance weight
on it. Improper flexplate balance will cause severe engine vibration.
Figure 4
Inspect converter stud holes, crankshaft
bolt holes and starter ring gear teeth for
damage, cracks and excessive wear.