April 27, 2016
Sonnax super hold servo kit 28821-09K is an all-in-one upgrade ideal for a competitive edge in GM Powerglide applications where racers are looking to reduce line pressure to free up horsepower. The kit's dual piston design features 30% more apply area to increase band apply force at your current line pressure or allow you to reduce line pressure by 20% to 30% while maintaining the same apply force.
A common question is, "I have an extreme application, how do I choose between the Sonnax Smart-Tech® servo and the super hold servo?"
Both are track-proven in today’s high-power vehicles. With its ratio-style release and supported pin design, the Smart-Tech 28821-10K is the best all-around upgrade that eliminates EVERY problem associated with the OE servo. Racers looking to reduce line pressure for greater efficiency will most benefit from the super hold servo’s 30% more apply area.
Hands down your Powerglide super hold servo kit finally cured my problems I chased for months. Looking forward to making the switch this off season to your Smart-Tech drum.T. Cannon