PAFO107: Ford Small Block 5-bolt (1961-64 Block Years) to Ford Modular (ref.6R80) V8 or Ford 6-Bolt Small Block (AOD) V8 Automatic Transmission Adapter Kit

Ford Small Block 5-bolt (1961-64 Block Years) to Ford Modular (ref.6R80) V8 or Ford 6-Bolt Small Block (AOD) V8 Automatic Transmission Adapter Kit

ADDITIONAL PRODUCTS AVAILABLE:  If you are planning to purchase a Shift Controller option with your Adapter Kit, please see the link below to add the Throttle-position Sensor (TPS) Adapter Kit to suit your application.

TRANSMISSION STAND-ALONE CONTROLLERS & TPS ADAPTER KITS - ADD-TO-ORDER HERE

KIT OVERVIEW

This premium adapter kit is specifically engineered to allow the use of modern and widely available 6-bolt Small Block Ford (SBF) and Modular transmissions with early 5-bolt SBF engines produced between 1961 and early 1964.

These early SBF engines (commonly 221, 260, and early 289 CID) featured a unique 5-bolt bellhousing pattern that is not compatible with later Ford transmission designs—until now. This kit completely overcomes that limitation, expanding your drivetrain options significantly.

Whether you're restoring a classic, building a restomod, or just looking to upgrade drivability and reliability, this adapter kit is a game-changer.

Fits the Following Engines:

• 221 CID V8 (1962–63)
• 260 CID V8 (1962–64)
• 289 CID V8 (early 1963–mid 1964) with 5-bolt bellhousing

⚠️ Note: Ford switched to the 6-bolt bellhousing pattern mid-1964. Please verify your engine has a 5-bolt bellhousing before ordering.

Compatible Transmissions:

This kit allows you to bolt a wide range of modern Ford automatic transmissions behind your classic 5-bolt SBF engine, including:

• C4 (6-bolt case)
• C6
• AOD
• AODE
• 4R70W
• 4R75W
• 6R80 (Ford Modular)
• 10R80 (Ford Modular)

This is the only known adapter kit on the market that provides compatibility between the 5-bolt SBF and late-model Ford Modular transmissions like the 4R70W, 6R80, and 10R80, offering you unmatched flexibility for modern drivetrains.

What’s Included:

• CNC-machined Adapter Plate
• Crankshaft Spacer – ensures proper torque converter engagement
• High-Torque Mini Starter – properly indexed for this application
• Inspection Cover Plate – for easy maintenance
• Complete Hardware Kit – Grade 8 fasteners included

Key Features:

• Preserves OEM Flexplate: Retains the stock 164-tooth, 14.25" diameter flexplate with correct engine balance.
• Torque Converter Compatibility: Works with OEM torque converters using the standard 11.4" bolt pattern.

Why This Kit Matters:

Early SBF 5-bolt engines were only produced for a short time and have long suffered from a lack of modern transmission options. Traditional swaps required rare or obsolete bellhousings and transmissions, which limited performance and serviceability. This adapter opens the door to a new era of reliability, gearing, and drivability by letting you use late-model transmissions with overdrive, electronic shifting, and stronger internals.

Installation Notes:

• Professional installation is recommended.
• Transmission crossmember and driveshaft modifications may be required depending on the application.
  
• ECM tuning may be necessary for electronically controlled transmissions (AODE, 4R70W, 6R80, 10R80).

FAQ:

Q: How do I identify if I have a 5-bolt or 6-bolt SBF engine?
A: Count the number of bellhousing bolts at the rear of the engine. Early 5-bolt engines will have a narrow, five-bolt pattern, while later engines (mid-1964 and up) use a wider 6-bolt pattern. The casting date code on the engine block can also help confirm compatibility.

Q: Can I use my existing flexplate and converter?
A: Yes, you’ll retain the OEM 164-tooth flexplate with the proper engine balance and standard 11.4" converter bolt pattern.

Upgrade Your Classic Ford the Right Way

Don’t let outdated transmission options limit your project. With this 5-bolt SBF to 6-bolt/Modular transmission adapter kit, you’ll unlock a world of performance possibilities while keeping your vintage V8 at heart. Whether you’re building a sleeper or a show car, this kit gives your early SBF the drivetrain it deserves.