Harrop 2300 Supercharger

Harrop 2300 Twin Helix Supercharger

We obtained the LQ9 FI Shortblock from Texas Speed with the full intention of putting an 88-94 mm Borg Warner Turbocharger on it. Loyd Mead purchased a Harrop 2300 Supercharger kit and put it on his 2004 GTO. It was one of the cleanest installs I had seen and the kit was very well put together. I immediately got interested in the Harrop and we bought a complete kit, New in the Box.

The LQ9 was not the average platform they had considered for the Harrop so we initially had to fabricate quite a few solutions to make everything fit. First, the coolant tanks were engineered to0 sit on the passenger side, as that is the driver’s side in Australia where they are made and sold. Steve fabricated a larger capacity reservoir to sit on the driver’s side fender.
That required us to move to an aftermarket overflow tank and to relocate the CPU from the drivers side inner fender (wheel well) to the interior of the car. Beyond that fabrication of a custom exhaust and heat shield were required for the Cold Air Intake.

OEM CPU location for 2004 GTO, Driver’s side inner fender

Free space after CPU Relocate

Key to the mod is to feed the wiring back through the dash

Profanity helps immeasurably, as a motivator

CPU on inside of cab kick panel. Another view of relocated CPU

Another view of relocated CPU

We also switched from a 2004 radiator to a 2005 radiator. The advantages were the overflow plumbing, the routing of the hoses, and the 2005 had gfreater capacity and also had the drain plugs.