Transmission Controllers - In Control

PCS Simple Shift ($599.00)

With a name like Simple Shift, you would expect it to be exactly that—simple to install and use. Once the harness is connected, all you have to do is set the dials on the side of the controller for the initial configuration as listed in the instruction manual, and you are ready for a testdrive. The initial setup is also the easiest, as you merely check TPS operation against the blinking light on the front of the controller. So right away, this controller was both affordable and easy to use, giving all appearances that it could be the most popular choice among car crafters. This was the third of the five controllers we tested, but we discovered we couldn't add more shift firmness beyond the most aggressive point. Jay Rohrback of Powertrain Control Systems (PCS) pointed out that we presented an interesting test by combining a very high- torque engine (more than 600 lb-ft) with a used transmission. Rohrback says PCS is considering offering a second controller for engines making more than 550 lb-ft of torque that would deliver additional trans pressure boost to hold that much torque. PCS sent one of these high-torque controllers to try, but it made only a minor improvement in shift firmness, and the trans still couldn't bark the tires during a WOT 1-2 shift at peak horsepower. This indicated to us that our trans was a little weak and could benefit from a shift improver kit. With a fresh trans, the shift firmness would have been more aggressive, with milder settings on the controller.

One cost of simplicity is a loss of finite control. For example, let's say you want the trans to shift at WOT at 6,200 rpm. Unfortunately, according to the instructions, the steps for WOT shift points 3 and 4 on the controller are either 6,075 or 6,425 rpm, respectively. There's no opportunity to set the shift point between these or any of the other steps. Each step at the higher engine speeds is about 6 percent, but in the lower engine speed it's closer to 9 percent. Just before we went to press, Rohrback informed us PCS will release a laptop-compatible program for the Simple Shift that will offer far more finite control and opportunities for tuning many of the shift parameters if that's something customers desire. So there you go.

TCI EZ-TCU ($614.95)

The TCI EZ-TCU is the only unit in our test fleet offering nearly complete hands-off tuning. The system uses self-learning software originally developed by its sister company, FAST, for the EZ-EFI system. The handheld unit will guide you through the initial setup once you have the system wired with a functioning TPS. The only inputs needed are the type of trans, rear tire diameter, rear gear ratio, speedometer output (which is only necessary if you are employing an electric speedometer), max shift rpm, and a very simple TPS calibration. With those completed, you can drive the car, and the EZ-TCU does the rest. Of course, if you want to go further into the setup, the handheld controller allows you to modify shift aggressiveness, shift firmness, and minimum speed for torque-converter clutch lockup. The handheld unit will also display lots of useful information such as rpm, mph, gear selected, trans oil temperature, battery voltage, and TPS percentage. If you're looking for a unit that requires the least amount of input that will get you driving with the least amount of fuss, this may be it. It's also important to note that if you are considering the TCI six-speed automatic that is based on the 4L80E, the EZ-TCU is the only controller we are aware of that will control this transmission. Overall, the system worked as advertised right out of the box. We modified the shift points slightly and adjusted when the lockup converter engaged, but other than a couple more mild changes including the maximum engine speed for shifts, the EZ-TCU performed flawlessly. Considering its affordability, it's tough to argue with this if all you want to do is plug in and drive.