Digital Solutions for Cadillac Engine Swaps

Quick Links:


"The E/K Display"

Finally, a stock-looking, integrated instrumentation solution for 1982-85 Eldorado and Seville owners who have swapped out their HT4100 and now have a defunct Fuel Data panel. Works with Diesels, too!


  • Oil Pressure 0-60 PSI
  • Engine Temperature 0-275F
  • Battery Voltage w/over-voltage alert
  • 'Loss of Oil Pressure' Warning
  • Two Over-Temperature Alarms
  • Torque Converter Lockup Feature
  • 3-Level Brightness Control or variable with Dash Dimmer
  • Compatible with all 1982-85 Seville and Eldo "MPG Sentinel" & "Fuel Data" Displays

The processor board, no bigger than a deck of cards, connects directly to your existing Fuel Data display and installs easily under the dash with its included case. Coolant Temperature, Oil Pressure and System Voltage are displayed at the touch of a button, and a new laser-etched overlay with factory-style text is included. Should you want to be warned of loss of oil pressure, or an engine over-temp situation, a single connection to the factory warning chime is all that’s required.

For minimal wiring, 3-levels of display brightness are built-in, or connect to your headlight switch/rheostat and the digits will dim variably with your other displays. Brightness has been calibrated to track the factory brightness curve.

A genuine problem after an engine swap is how to lock up the transmission torque converter.... The processor board also handles that! It prevents TCC engagement until the engine is warm, provides a delay after input conditions are met to prevent short cycling, and keeps the existing TCC brake switch for quick disengagement. Plus it works with the normally-closed 4th Gear Switch these cars use.

Each unit is hand assembled, programmed, calibrated and comes with everything needed for easy installation.

August 2022 Update:

Pricing and availability is expected to be announced this fall. Multiple units have been built and are undergoing testing to prove out durability and fine-tuning of software features. Stay Tuned for Updates!


"The TCC+"

A reasonably-priced Torque Converter Lockup solution designed specifically for HT4100 Engine Swaps.


  • Uses Engine Temp to avoid Early Lockup
  • Selectable Time Delay Prevents short-cycling
  • Compatible with the '82-'85 Cad "N.C. 4th Gear Switch"
  • Engine Over-Temp Alarm: Operates Coolant Temp Light & Factory Chime
  • 2-Wire Trans Connection at ECM. No need to drop the pan!

This microprocessor-controlled torque converter controller is especially designed for 1982-85 325-4L and 200-4R transmissions originally used with HT4100 engines. Even if you retain the factory ECM, it'll operate in limp-home mode due to loss of its other inputs, and that means no torque converter lockup. There's also the matter of the Coolant Temperature light no longer functioning as the 4100's engine temp sensor no longer exists for the ECM to monitor. And if you have a digital speedometer, which moves the Temp light down into the hard-to-see Info Center area, you'll appreciate the engine over-temperature alert which is capable of driving the factory warning chime.

Of course, there are aftermarket solutions, but the ones I've found seem to fall short on features and performance, especially for the price. And the unique 4th Gear Switch these Cadillacs use works in an opposite manner to the other divisions which presents a compatibility problem for most designs.

Should you only want TCC lockup with minimal fuss and wiring, only 4 connections are necessary, all available at the ECM under the passenger dash: Power, Ground, and 2 wires for the trans.

Includes inline fuse holder, temp sensor & pigtail, plus flanged case and installation instructions.

Stay Tuned for Updates!