Exterior Components› Body Panels and Components
Sun Coast Converters
Suncoast Converters Boost Valve Kit 104520-12K
SKU: S02K 104520-12K
Moderate — 2–4 hours
Description
This kit addresses issues such as insufficient line rise, soft shifts, and burnt clutches that can occur in these GM transmissions. The problems are often caused by the oscillation of the boost valve within the boost sleeve, leading to wear and fluid pressure leaks.
The Sonnax kit features upgraded materials and minimal clearances to prevent wear and restore proper hydraulic control. It includes a boost valve, sleeve, and spring, with the sleeve made from wear-resistant billet aluminum. A larger EPC feed orifice is incorporated for quicker throttle response, and the included spring provides a modest 5 psi increase across the pressure curve. The boost valve parts are designed as a drop-in solution for quick installation.
Fitment
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Specifications
| Brand | Sun Coast Converters |
| Part Number | S02K 104520-12K |
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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