
Line Pressure Booster Kit 4L80-E, 4L85-E
- Valve
- Sleeve
- Pressure Regulator Spring
- O-Rings (2)
Our pressure regulator springs are approximately 10% stronger than OE and more conservative in impact than other aftermarket kit springs. Large ratio boost valves provide higher pressure incrementally and when it is needed the most. The combination of these springs and valves in a Sonnax kit 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.
- Achieve shorter shifts and increased torque capacity without creating low-speed harshness
- Improved band and clutch holding capacity for increased durability
- Progressive pressure increase as driving conditions become more demanding
- All the benefits of increased line pressure without overloading the pump at idle
- Simple and affordable drop-in solution with no special tools or reaming required.
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.