Drivetrain› Automatic Transmissions and Components
Circle
258mm Pro Series Torque Converter for 4R100/E4OD
SKU: 31-13-05
Moderate — 2–4 hours
Description
Construction includes 100 square inches of clutch lining for WOT lock-up, furnace brazing, and hand TIG welding. It also utilizes Torrington bearings, a billet front cover, and a billet piston. The impeller hub is flanged for durability, and the assembly is hand-assembled to exacting tolerances. This converter boasts a lightweight yet strong design.
Fitment
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Available on iOS & Android
Specifications
| Brand | Circle |
| Part Number | 31-13-05 |
| Category | Drivetrain |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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