Speedmaster®
Ford 4 Speed Wide Ratio Aluminum Toploader Gearbox Transmission [Short]
![Speedmaster® PCE646.1002 Ford 4 Speed Wide Ratio Aluminum Toploader Gearbox Transmission [Short]](https://product-arena.s3-us-west-1.amazonaws.com/ProcompElectronics/PCE646%20-%20Manual%20Transmissions/PCE646.1002/PCE646.1002.jpg?resizeid=224&resizeh=600&resizew=600)
![Speedmaster® PCE646.1002 Ford 4 Speed Wide Ratio Aluminum Toploader Gearbox Transmission [Short]](https://product-arena.s3-us-west-1.amazonaws.com/ProcompElectronics/PCE646%20-%20Manual%20Transmissions/PCE646.1002/PCE646.1002_A.jpg?resizeid=224&resizeh=600&resizew=600)
![Speedmaster® PCE646.1002 Ford 4 Speed Wide Ratio Aluminum Toploader Gearbox Transmission [Short]](https://product-arena.s3-us-west-1.amazonaws.com/ProcompElectronics/PCE646%20-%20Manual%20Transmissions/PCE646.1002/PCE646.1002_B.jpg?resizeid=224&resizeh=600&resizew=600)
![Speedmaster® PCE646.1002 Ford 4 Speed Wide Ratio Aluminum Toploader Gearbox Transmission [Short]](https://product-arena.s3-us-west-1.amazonaws.com/ProcompElectronics/PCE646%20-%20Manual%20Transmissions/PCE646.1002/PCE646.1002_C.jpg?resizeid=224&resizeh=600&resizew=600)
Product Information
Overview
This Speedmaster manual transmission is built with all brand new components and case. Designed for engines producing up to 500hp, all components are hand fit and assembled in USA for the ultimate in precision fit and finish.
Specs
| Brand: | Speedmaster |
| Part Number: | PCE646.1002 |
| Part Type: | Manual Transmission |
| Number of Gears: | 4 |
| Gear Ratio: | Wide |
| Input Shaft Diameter (in.): | 1.0625 in |
| Input Spline Quantity: | 10 |
| Output Shaft Spline Quantity: | 31 |
| Output Shaft Spline Diameter (in): | 1.360 in. |
| Tailshaft Length: | Short |
| Bellhousing Included: | No |
| Yoke Style: | Slip-on |
| Yoke Included: | No |
| Shifter Included: | No |
| Shifter Style Required: | Long |
| First Gear Ratio: | 1:2.78 |
| Second Gear Ratio: | 1:1.92 |
| Third Gear Ratio: | 1:1.35 |
| Fourth Gear Ratio: | 1:1.00 |
| Case Material: | Aluminum |
| Quantity: | Sold Individually. |
Warranty Information
12-Month Limited Worldwide Warranty
Prop 65 Warning
This product may contain chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
Installation Guide
Our AI assistant generates a step-by-step guide for this product — covering installation, maintenance, and troubleshooting.
This AI-generated guide is for general reference only and does not constitute official Speedmaster product documentation. Always verify fitment, torque specifications, and safety requirements before installation.