Model A & B
Ford Garage
Ignition Components Table
The table below is a summary of the era aftermarket ignition interchange part numbers for the typical Model A and B Ford ignition tune-up items such as points, rotors, condensers, distributor caps, etc.
Original Model A (and later Model B) ignition systems were designed and produced for Ford by the Electric Auto-Lite Company of Toledo, Ohio, and by the American Bosch Magneto Corporation, based in Springfield, Massachusetts.
OEM ignition components supplied to Ford by Auto-Lite (AL, A) and American Bosch included complete distributors and hardware, as well as electrical components such as coils, points, and condensers.
In 1930, the American Bosch Magneto Corporation (AB) was combined with the US branch of Robert Bosch A.G. of Germany to form the United American Bosch Corporation.
Beginning in late 1931, Essex Wire Corporation (SX) began supplying Model A and B ignition coils to Ford. Essex was already a major producer of OEM wire harnesses and battery cables for Ford beginning in 1930. Essex's manufacturing facilities were located in space leased from Ford at the old Highland Park (Model T) assembly plant.
The table below will help you spot and identify NOS and NORS ignition parts at swap meets. These older vintage OEM replacement parts are often better quality and materials, and more dimensionally accurate than currently available reproduction parts, other than possibly condensers as discussed further below.
Do you have any other part number interchange data to add to the table?
Description |
Year |
Ford | Bosch | Auto-Lite | Niehoff | Filko | Standard Motor Products/ Blue Streak |
Echlin NAPA |
AMPCO | Motorcraft | Other |
|---|---|---|---|---|---|---|---|---|---|---|---|
| A Contact Points Set | 1928-31 | A-12199 | FF-14-15 | 48-45 | FD 1718 | CS 30 | F 81 | DP-104 | BorgWarner A123 | ||
| A Contact Arm | 1928-31 | A-12162 | IL-78030 | IGF-3003-A | FF 14 | FB 48 | FA 16 | ||||
| A Contact Screw | 1928-31 | A-12172 | CS-79814 | IGF-86 | FF 15 | FC 45 | FA 7 | ||||
| B Contact Points Set | 1932-34 | B-12199 | FF-23-15 | 49-45HD | CS 30 | F 82-W | Shurhit Set 38 Sorensen FO-21-22 |
||||
| B Contact Arm | 1932-34 | B-12162 | FF 23 | FB 49 | FA 14 | Shurhit 1A-50 | |||||
| B Contact Screw | 1932-34 | B-12172 | FF 15 | FC 45 | FA 7 | Shurhit 1B-53 | |||||
| A Condenser * | 1928-31 | A-12300 | CD-77949 | 1GF-2004 | FO 200 | FD 11 | FA 5 | F 580 | DC-1 | Carquest GAA1119 PDC Gold Band F-580 |
|
| B Condenser * | 1932-34 | B-12300 | FF 21 | FO 201 | FD 55 | FA 10 | F 581 | ||||
| Rotor | 1928-34 | A-12200 B-12200 |
SA-77946 | IGF-1026 | FF 12 | FO 71 | FD 15 | FA 3 | F 901 | BorgWarner BWBD34 GP Sorensen FE76 Carquest Wells 515589 Shurhit D-34 Taro 900BB |
|
| Distributor Body * | 1928-34 | A-12105 B-12105 |
FO 70 | FD 22 | F 900 | Western Auto/ Wizard LR4215 Taro 902BB |
|||||
| Distributor Cap | 1928-34 | A-12115 B-12115 |
FO 70A | FD 21 | FA 9 | F 902 | Taro 902AB | ||||
| "Hi-Speed" One-piece Round Distributor Cap |
1928-34 | FF 71 | F 928 | Taro 901BB | |||||||
| A Upper Plate Asm with Points |
1928-31 | A-12150 | FF 106 | BA-2 | |||||||
| A Upper Plate Asm w/o Points |
1928-31 | A-12151 | SA-78192 | IGF-1082 | BA-2LP | FD 29 | FA 30 | ||||
| A Lower Plate Asm | 1928-31 | A-12148 | SA-79835 | IGF-1064-A | BA-20 | F 3811 | |||||
| B Upper Plate Asm with Points |
1932-34 | B-12150 | |||||||||
| B Upper Plate Asm w/o Points |
1932-34 | B-12151 | |||||||||
Description |
Year |
Ford | Bosch | Auto-Lite | Niehoff | Filko | Standard Motor Products/ Blue Streak |
Echlin NAPA |
AMPCO | Motorcraft | Other |
*Condenser:
The May 29, 1930 Ford detail drawing of the A-12300 condenser indicates it to be optionally a Bosch CD-77949, or an Auto-Lite 1GF-2004.
It is generally NOT recommended (and may be unreliable) to use NOS or older vintage condensers due to the technology used to produce them. Many of them are subject to failure due to perforation of the internal wax paper type insulator, which separates the foil layers.
This risk of failure is compounded by the physical location of the condenser on a Model A. It is placed inside the cast iron distributor casting, just above the cylinder head, and in close proximity to the exhaust manifold.
The Model A condenser is in a high-temperature environment with little air circulation or cooling. Virtually all other automotive condensers are placed higher up and away from engine heat.
These condensers have a modern polyester (Mylar) film construction and are better able to withstand the high heat conditions found in the Model A application.
*Distributor Body:
The 1928 Bakelite Distributor Body is characterized by a single locating notch to the distributor casting pin and a tall window with radiused upper notches (for stress relief) for the movable point plate arm to extend through.
The 1929-31 Distributor Body A-12105 is characterized by a single locating notch to the distributor casting pin and a tall window with square upper corners for the movable point plate arm to extend through.
The 1932-34 Distributor Body B-12105 was initially designed to be backwards compatible and work with both the Model A and Model B distributor casting pin locations. It is characterized by having two locating notches so as to fit either distributor casting pin, and with a short window with square upper corners for the fixed Model B point plate arm to extend through.
In addition, however, the B-12105 had a thinned-out rectangular section above the point plate arm notch, which could be broken out with pliers so as to also fit a Model A distributor. It was designed with a nominally short window to better fit the more sensitive Model B distributor (with its centrifugal advance mechanism) and better seal it from dust and insects, etc.
Most aftermarket and reproduction distributor bodies are designed with a nominally tall square window like a later Model A but also have two casting pin notches to fit both the Model A and Model B distributor.
More related information on Ford Garage:
- For more Model A & B related information, use the Site Search box at the top or bottom of this page.
- Model A Condenser Capacitance
- Model A & B Condenser Details
- Model B & Model 46 Distributor Design Details
- Model B & Model 46 Distributor Advance Operation
- Model B & Model 46 Pertronix Ignitor Distributor Timing Procedures
- Model A Remund Pertronix Electronic Ignition Instructions
- Model A & B Engine Cam/Valve and Ignition/Spark Timing Discussion
- Model A, B, & Model 46 Camshaft Gear Timing Cover Differences
- Model A Distributor Lower Plate Wiring Solution
- Model A Nu-Rex Centrifugal Spark Advance Unit
February 2008