1968 428 Cobra Jet Drag Strip Modifications

The March 1968 edition of Autolite Shop Tips includes a comprehensive description of the modifications made to prepare the 1968 428 Cobra Jet engine for drag strip duty in the Stock and Super Stock classes. Here's a summary (part numbers are service part numbers unless noted as engineering part numbers):

Component Production "C" Stock "E" Super Stock
Cylinder Head C8OZ-6049-F
Engineering Number C8AE-6090-J
Same Same
Intake Manifold
(Aluminum)
C6AZ-9424-H
Engineering Number C7AE-9425-F
Same Offset 427
C6AZ-9424-M
Engineering Number C7AE-9425-C
Intake Manifold
(Cast Iron)
C8OA-9424-A
Engineering Number C8OE-9425-A
Same N/A
Carburetor, Manual
(735 cfm)
C8OZ-9510-AA Same Same
Carburetor, Automatic
(735 cfm)
C8OZ-9510-AB Same Same
Camshaft Hydraulic
C6OZ-6250-B
Hydraulic
C8AX-6250-C
Solid
C8AX-6250-D
Valve Spring Not Specified 427 Type
C5AZ-6513-A
Crane or H-M Type
spring, retainer, push rod, and tappet
Rocker Arm Non-Adjustable 1.73:1
B8AZ-6564-C
Adjustable 1.76:1
B8A-6564-B
Adjustable 1.76:1
B8A-6564-B
Adjustable 1.76:1
B8A-6564-B
Exhaust Valve C3AZ-6505-E Same Lightweight, Sodium-Filled
C8AX-6505-B
Intake Valve C3AZ-6507-AJ Same Lightweight, Hollow Stem
C8AX-6507-B
Valve Lifter Hydraulic
Part Number C3DZ-6500-B
Hydraulic
Part Number C4TZ-6500-A
Crane Lightweight or
427 Type C4AZ-6500-B
Piston
(Cast Aluminum)
C6AZ-6108-AY, 10.7:1 CR Forged, Dished/Eyebrows
11.0:1 CR
Forged, Flat top/Eyebrows
11.6:1 CR
Piston Rings C6AZ-6148-A Moly Type Moly Type
Piston Rods P.I. Type
C6AE-6200-F
427 Type
C5AZ-6200-D
427 Type
C5AZ-6200-D
427 Type
C5AZ-6200-D
Crankshaft C6AZ-6303-B1 Same Same
Oil Pan C6OZ-6675-A Deep sump 9-quart
C5AE-6675-N
Same
Oil Pickup C6OZ-6622-A C5AE-6622-C Same
Oil Filter C1AZ-6731-A Low Resistance
C8AE-6714-B
Same
Distributor C8OZ-12127-D Dual point, 427 Type
C5AZ-12127-E
Same
Exhaust System Not Specified Jardine or Doug's Type headers Same
Vibration Damper Not Specified Heavy Duty 427 Type Same
Clutch Not Specified Production Auto. and Manual Heavy Duty #2650 Type
Transmission 2.32, 1.69, 1.29 ratios Production/blocker rings cut
Line lock
Same
Rear End 3.89:1, no locker 4.44:1/242L Detroit Locker 4.71:1/242L Detroit Locker
Suspension Not Specified 32" traction bar right side
Single link bar left side
32" traction bar both sides
Shocks Not Specified Heavy Duty Type Same
Tires F70 Firestone 8.90x14, 7" Tread 10.50x15

Shipping weight: AMA's Mustang fastback 3267 lbs., hardtop 3243 lbs.