6L80, 6L90 (300mm), 6L80, 6L90 (300mm), Multi-Plate Performance Converter

JMBV Performance Converter Kit
Part No. GM-RK-23

View Instructions

The GM Corvettes that use the GM 6L80, 6L90 (300mm) torque converter often have engine modifications for increased output, which can quickly push the stock, single-disc converter clutch past its capacity. For Corvette customers with more demanding applications, Sonnax offers JMBV performance converter kit GM-RK-23.

This dampered, 300mm multi-plate upgrade employs a forged three-pad cover, forged piston and three woven carbon friction elements for significantly increased clutch capacity and durability. By reusing the OE damper with the Sonnax clutch plates (bonded with OE woven carbon friction material), GM-RK-23 ensures optimal TCC apply and release characteristics, as well as slip rates that match OE continuous slip calibrations. Drivability is excellent. This easy-to-build and cost-effective kit includes clear, concise instructions.

While testing this kit, Sonnax found that the pressure needed to keep this multi-plate TCC slipping at the calibrated rate was much less than the pressure needed in a comparable single-disc converter. Because the Sonnax multi-plate clutch needs less pressure, there is less demand placed on transmission electronics and hydraulics. With the GM-RK-23, it's easy for the transmission to keep the TCC slip within required slip parameters.

Enhanced design features include:

  • OE friction material bonded to each clutch plate
  • Forged components assure rigid apply and reaction surfaces
  • Lathe turned feature on mount pads identifies this kit as a multi-plate
  • Added clutch capacity reduces required lockup pressure
  • Lower operating pressure reduces demand on transmission electronics and hydraulics

This converter kit requires a salvaged inner damper plate from a GM 6L80 or 6L90 converter.

The converter sticker codes found on 6L80/90 full size converters are not always consistent. In particular, the JMDZ code can be found on both gas and diesel types of these converters. Be sure to check the bolt circle diameter and overall converter height to verify the Sonnax kit is designed for your application.

  • Front Cover
  • Clutch Plate with External Splines
  • Clutch Plate with Internal Splines
  • Piston
  • Rivets (8) 2 Extra
  • Transmission Unit: 6L80, 6L90
  • Core: GM 300mm
  • Dampered: Yes
  • Lockup: Multi-Plate
  • Unit Size: 300mm
  • Clutch Material: Woven Carbon
  • Turbine Hub Input Spline Count: 36
  • Bolt Circle Dia.: 9.21"
  • Bolt Count: 3
  • Assembled Height: 6.271"

Where to Buy

  • Existing Customers: Contact your sales representative.
  • New Customers: Fill out the form and a sales representative will contact you.
  • 6L80, 6L90 (300mm), 6L80, 6L90 (300mm), Multi-Plate Performance Converter JMBV Performance Converter Kit GM-RK-23
  • 6L80, 6L90 (300mm), 6L80, 6L90 (300mm), Multi-Plate Performance Converter JMBV Performance Converter Kit GM-RK-23 details


6L80, 6L90 300mm Converter Heavy-Duty Builds Explained

Sonnax Performance Converter Kits

Engineered to Deliver Builds that Last

Designed from the ground up to outperform OE and other aftermarket components, Sonnax has you covered with a full line of performance converter kits for gas and diesel vehicles. Offering the widest variety of options in the aftermarket, these innovative kits deliver customized performance and value.

  • Small/Large Diameter
  • Single-Plate/Multi-Plate/Non-Lockup
  • Dampered/Damperless

Choose the right kit for your rebuild!