Last time, Junior and Alex removed the old harness and factory ECM, then routed the custom Casper's Electronics wiring harness into the cabin. | 
Installing XFI into a Turbo Buick is made easy by Casper's Electronics. Its ECU Adapter Module plugs the XFI ECU to the 1986-1989 Turbo Buick/TTA engine harness-no cutting or splicing involved. |
We'll be using other tricks to get the most out of the XFI install. This is a MAP Adapter Plug-In from Casper's, an ingenious piece that plugs into an in-cabin wiring harness and enables the user to keep a stock-location 3-bar MAP sensor, as opposed to using a remote 3-bar MAP. | 
The new Casper's wiring harness (upper right) comes into the cabin and snaps into the ECU Adapter Module. The MAP Adapter connects into the black bulkhead wiring harness under the glovebox, and its connector snaps into the Casper's ECU Adapter MAP sensor connection. The Wideband O2 harness connection clicks into the white/grey WBO2 ECU Adapter as well. |
Next, the four male ends of the ECU Adapter simply snap into the female XFI ports. There's one ground wire on the Adapter that needs to be bolted down too. | 
The wideband O2 sensor is installed into a pre-existing bung in the Buick's 3-inch downpipe. |
That's it! The XFI is now connected to the vehicle. The black plug in the foreground is the laptop hookup, which connects into a cable with a USB port on the other side, an easy interface into the computer. | 
I get the laptop up and running, grab the XFI CD-ROM, and install the XFI software. The cable is hooked up and we're ready to begin tuning. |
Cal Hartline of Hartline Performance will be handling the tuning. He starts by verifying the timing and checking that all of the sensors are operating correctly. Next, he installs a Hartline startup program, which is placed in XFI's GCT calibration file folder and loaded into the car. Though the XFI ECU retails for just over two grand, Hartline Performance has a Turbo Buick-specific package that includes the XFI, a Buick adapter harness, a 3-bar MAP, and tech support for $1,850. What makes this such a screamin' deal is the fact that Hartline installs a custom calibration for the customer's specific combination, the latest software, and the latest flashware in each XFI unit. Though I got my XFI box directly from FAST, Cal uploads the Hartline Performance upgrades and calibration. If you got your XFI elsewhere, Hartline charges a nominal fee to tune your system. | |