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- Line Pressure Booster Kit
- 5R55S, 5R55W
Affordable Kit for Big Performance without a Big Price Tag
The larger boost valves and stronger PR springs in Sonnax booster kits raise line pressure the SMART way by controlling pressure increase progressively with the demand of driving conditions.
- Simple, affordable parts require no special tools or reaming to install.
- Slightly stronger springs provide a modest base line pressure increase. Unlike other, stronger aftermarket springs, Sonnax springs won't overload the pump at idle.
- Larger boost valves deliver demand-based line rise without low-speed harshness. How Progressive Boost Works:
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The combination of Sonnax booster kit valves and springs gives you the best of both worlds: a modest pressure increase at the low end, with a high-end pressure that is equal to or greater than that of other aftermarket kit springs.
The combination of boost valves and springs is the ONLY way to progressively increase line pressure.

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