Wilcap Co.

Cadillac Engine Adapters & Parts


Part Number Guide

303=331 C.I OHV V8(We call it a 303 because it shares a very similar bolt pattern with the Oldsmobile 303 C.I. engine.) 1949-1953 Cadillac
346=1938-1948 346 C.I. Cadillac Flathead V8
CAD=1954 -1963 331,365 & 390 C.I. Cadillac OHV V8
AT=Automatic Transmissions
MT=Manual Transmissions
350= Chevrolet Small and Big Block Bellhousing Bolt Pattern
302= Ford 1965 up Ford Small Block Bellhousing Bolt Pattern
BOP=Buick Olds Pontiac Cadillac (1966 to 1986 Iron Block V8) Bellhousing Bolt Pattern
FE= Steel Billet Flywheel
AL = Aluminum Billet Flywheel with Steel Friction Face


1955-1963 Cadillac Engine to GM V8 Automatic

cad350 diagram


CAD-350ATChevy (Also Available with BOP Pattern) Download PDF



cad-350mt diagram


Adapter Kit comes with Adapter plate, Flywheel, Pilot Bearing Adapter and fasteners. Download PDF

** Starter is Mopar Small Block (318, 340, 360) (Not included in kit)

Note 1.. Matched Chevrolet transmission and Bellhousing. 10.5" Bell is recommended.

Note 2. Flywheel is drilled for 10.5" B&B/Diaphragm bolt pattern. Clutch disk is 10.5 with your transmission input shaft splines.



CAD-350MTChevy (also available for use with BOP bellhousing)



CAD-EFM uses Ford 8RT bellhousing from 49-53 Ford truck or Mercury





BH 303-350

303-EFM adapter plate Download PDF with modified 59A-350 bellhousing to use with 32-48 Ford Style Throw Out Bearing



303-EFM adapter plate 1949-1953 Cadillac Engine to 1932-1948 Ford, Mercury Transmissions Download PDF




Miles chassis

CAD-302 Installed

The CAD-302 Allows the use of the Small Block ford bellhousing and transmission to the back of the 55-63 Cadillac engine





 Part Number

 Description / Material

 Ring Gear

 Avail. Pressure Plate

 FW303M 1949-1955 Marine flywheel  Aluminum  145T None
 FW303AL 1949-1955 Aluminum  With Steel Insert  145T  4,5,6,7
 FW303S 1949-1955 Replacement Steel  145T  4,5,6,7
 FWCADM 1956-1963 Marine flywheel  Aluminum  176T or 166T  None
 FWCADAL 1956-1963  Aluminum  With Steel Insert  176T or 166T   4,5,6,7*
 FWCADS 1956-1963 Replacement Steel  176T or 166T  4,5,6,7*
 FWCAD350M  Marine Aluminum for use w/adapter  130T  None
 FWCAD350AL  Aluminum W/Steel Insert for use w/adapter  130T 6
 FWCAD350FE  Steel for use with adapter  130T 6


*166T Flywheels not available with 11" PP Patterns. 145T & 176T ring gear flywheels may require use of customers torus cover ring gear depending on availability of NOS ring gears.

Pressure Plate Bolt Patterns;

 1.  8" Diaphragm
 2.  8.5" Diaphragm
 3.  9 1/8", 9 1/4", 9.5" B&B and Diaphragm
 4. 10", 10.5", 10.95" B&B and Diaphragm
 5. 11", 12" B&B and Diaphragm
 6. 10", 10.5" Long and 10" B&B and Diaphragm
 7. 11" Long and Diaphragm
 8. 11.5" & 12" Long and Diaphragm



Flywheels not listed in our store require more information. Plaese call or email for details




1949 to 1954 331 C.I. have the cast in bellhousing with the starter bolted to a removable housing


1955 to 1964 331,365 & 390 C.I. Have a modern style "Flat Back" block with the starter bolted to the original bellhousing.


Flathead Cadillac 1936-1948 346 C.I. Note; the dowel pin location and crankshaft bolt pattern vary depending on the original transmission

346cadblock ID

Wilcap Company

806H S. Division St. Waunakee, WI 53597

(608) 509-1113

EMAIL https://transmissionadapters.com/pages/contact-us

NOTE; Please Put "Wilcap" in subject line of email