•Previously, we took you through the necessary steps for installing a modern electronically-shifted 4L60E trans into your third-gen. But we only got you half way there. This month we made a trip over to Westech Performance in Mira Loma, California, where their electronics guru, Ernie Mena helped us put the brains behind the brawn and added a TCI electronic Transmission Control Unit (TCU) (PN 377500l, $774.38). The introduction of electronically-controlled transmissions which use a computer to tell the trans when, where, and how to shift, has done wonders for the performance and durability of GM overdrive units. And with a computer calling the shots, you won’t have to deal with the frustration of having your trans shift into overdrive too early or too late.
TCI has gone to the next level by giving the end user the opportunity to custom tune their trans by using a simple software interface and personal computer (TCI has recently released a stand alone data logger that allows you to do the programming once the TCU has been initially setup with your computer). After following a simple step-by-step setup wizard, the TCU program allows you to modify numerous aspects of your transmission's behavior with a laptop computer, including converter lock-up, shift points, and line pressure.
The majority of this installation involves wiring and computer input, so if you’re not comfortable with crimping and cutting, or basic PC functions, it may be best to leave this install to a professional.