Dinan’s driveline tuning components were designed to deliver maximum acceleration by multiplying torque and making more efficient use of available power. After increasing the engines output, driveline modifications were necessary to ensure reliability and further increase performance.

Automatic Transmission Chip – $199.00

Transmission chips reprogrammed the computer-controlled automatic transmission for optimum acceleration.  “Economy” mode shifting remains the same at light loads but automatically becomes programmed to “Sport” mode at full throttle.  This eliminates the need to manually shift form “Economy” to “Sport”.  The “Sport” mode is reprogrammed for higher shift points, allowing you to take full advantage of the increased horsepower and raised rev-limits.

(1) Installation Hour

Automatic Transmission Shift Kit – $495.00

The Dinan Shift Kit improves reliability and performance by making shifting more rapid and reducing clutch slippage.

(4) Installation Hours

Automatic Transmission Cooler – $595.00

With an automatic transmission, improved reliability comes from an external cooler to reduce transmission fluid temperatures.

(5) Installation Hours

High Stall Torque Converter – $795.00*

Additional improvements in performance came from a higher stall speed torque converter.  The 8-Series BMW’s original stall speed is 1900 rpm; Dinan raised the stall speed to 2400 rpm.  The higher stall speed torque converter allowed the engine to rev higher before acceleration begins.  The higher rpm puts the engine into its peak power rage sooner.  The Dinan torque converter retained the lock up feature into its 3rd and 4th gears to maintain fuel economy at cruise.

(6) Installation Hours

* Exchange Price – $1,300 Core Deposit

Note: Must be used with a transmission cooler.

Limited Slip Differentials – $2,290 to $3,200

Dinan offered Limited Slip Differentials for improved handling and acceleration of the 8-Series BMW.  Limited slip was not available as a factory option on the original 850i.  In addition to enhanced performance, a limited slip differential provides for improved traction in adverse weather conditions, such as snow and ice.

The 850i was factory equipped with 3.64:1 gearing on the automatic and 2.65:1 on the 6 speed transmission.  In additional to adding limited slip, Dinan was also willing to alter the gearing for improved acceleration or top speed emphasis.

  • 2.65:1 (6-speed) – $3,200**
  • 3.15:1 (Auto) – $2,295.00*
  • 3.64:1 (auto) – $2,295.00*

*  Exchange Price – $350.00 Core Deposit

** Stock differential must be shipped to Dinan for modification 

Note: Stage II and Stage III Twin Turbo cars can exceed 200mph with a 3.15:1 differential.