When Carl Thompson's quad-rotor Lexus GS300 first broke cover back in 2013, there was no one denying the turbo quad-rotor was a game-changer, internet atom bomb, and a mechanical masterpiece of the likes never before seen in New Zealand. But getting a ‘hot rod’ like the Lexus to work in perfect harmony has been a bit of an ongoing process, because, let's face it, you can't exactly go down the road and buy some off-the-shelf components. While the car has always worked, Carl is some what of a perfectionist, and having things so-so has never been his style.
Eyeing up a trip to compete at Sydney Motorsport Park in October 2016 for the World Time Attack's International Drift Challenge for some time now, no bolt has been left unturned in preparation. CBR, SMS, CMC, and C's Garage have been hard at work making a raft of changes to not only make the car more serviceable, but also competitive. When we checked in on the car, the team was just completing final assembly before it was to be tested over the week of August 22.
One of the biggest changes has seen a complete rework of the rear end. The rear-mounted oil cooler has been ditched in favour of twin front mounts. This required new sheet metal. When we arrived, the car had just returned from paint and panel with a fresh coat of white on the all-new sheet metal, and a few subtle exterior changes had been made as well.
The boot rework has seen a smaller Fuel Safe cell added, along with a large 7.5-litre surge tank. Three Weldon 2500hp fuel pumps move the E85 around, one acting as the low-pressure lift pump and the other two as the feed pumps, all controlled through the PDM. The oil tank for the dry sump has also been relocated to the boot.
The boot lid is quick-release and will allow easy access to the fuel filler, which will be getting plenty of use. Like all the custom alloy components found up front, the rear components have been black-anodized. Carl chose anodizing over powder-coating as it's harder wearing and solvent-resistant.
Engine-wise, things have changed considerably since our 2013 shoot, with almost everything external upgraded. A new high-flow Peterson R4 dry-sump pump shares a CMC alloy mount with the Nations 400amp alternator.
The turbo is a giant Garrett GTX55 with dual TiAL 60mm gates feeding directly off the exhaust housing and exiting skywards through the bonnet. Boost control is handled by the Turbosmart E-boost, and is currently set at 30psi, making 1250hp at the rear wheels. The five-inch dump pipe is a tight fit, and splits to dual four-inch pipes under the car for ground clearance. There is an option to run a single custom-built muffler, but SMSP (Sydney Motorsport Park) does not have noise restrictions, so this will be left at home in New Zealand.
The rework of the engine bay has been a lengthy one. The new intercooler is a large Bell unit with lobster-backed piping, Plazmaman boost clamps, and a 100mm Plazmaman throttle body. Both the radiator and oil coolers use locally sourced cores with SMS tanks. Hidden somewhere within that piping is a large-capacity Meziere electric water pump.
There is now some serious firepower in the form of M&W CDI, with 4x Pro-Drag2 CDI units. The ECU itself has just been upgraded to Microtech's latest and greatest. Such a powerful ignition system is a must when you have 16 1600cc Bosch injectors delivering fuel.
The car has also been rewired using a SmartWire PDM system, making it a much easier way to troubleshoot any problems. As you can imagine, the wiring with such an engine package is very complex with a multitude of senors needed. Going SmartWire was a no-brainer really.
A Racepak IQ3 dash now replaces the bank of Autometer gauges, and gives the ability for data logging and a completely configurable display. There is also now a Holinger six-speed sequential and Direct Clutch Services sintered iron twin-plate mated to the four-rotor allowing Carl better wheel-speed control and ability to keep that big Garret on song.
One area that has stayed constant is the Koni two-way adjustable coilovers with adjustable four-link, and adjustable watts link with roll-centre adjuster. The sheet-metal diff with Strange alloy nine-inch head, and set of Endevour Engineering floating hubs and axles, have also been in the car since day one. While some might think the live axle is old tech, make no mistake, this car has no trouble with mechanical grip, and the set-up has been bulletproof thus far.
Gone is the Wilwood Superlite brake set-up, as it had trouble pulling the car up from high speed. In its place are Brembo monoblock six calipers up front and dual four-pots on the rear, with Brembo sprint pads. The rotors are 380mm up front and 355mm on the rear with custom alloy hats by Mike at CMC. The Sydney event will mark Carl's first international event, and with the calibre of drivers and cars that he will be going up against, he is certainly making sure that he is well-prepared for the job and not just there to make up the numbers. And a word of warning to any driver who will attempt to follow the Lexus — start practicing driving blind as this machine will be leaving one hell of a 1250hp smokescreen.