Trans-Am Mustang Feature
Over the past couple of years there has been an influx of Trans-Am spec cars finding their way into the country. I remember seeing one at a test day 2 years ago now and I recall being impressed by how simple it all looked from the surface. Now that I've spent some time with the Wall Racing number 38 Mustang and seeing just how quickly Timmy Brook can hustle the thing around Wakefield Park on a test day last week I was intrigued at what these things are and what makes them tick.
BODY AND CHASSIS
A Trans am car – also referred to as a ‘TA2’ car in the US – is based around a space frame chassis with the choice of three different composite bodies. As you might have spotted, our man Timmy is rocking a Ford Mustang, but there are also Chevrolet Camaros and Dodge Challengers in the field.
But the differences only run skin deep, and despite their American dimensions each cars weighs exactly 1,250kg including the driver – 30kg less than the TGR86 Series cars that Tim dominated in.
DRIVELINE
Like the chassis, the engine is a control item to ensure close racing. The block is a GM sourced LS3 that runs an LS9 dry sump system which equates to 525hp sent to the rear wheels. No fancy fuel is used here, the Trans Am cars all run on 98 octane fuel supplied at events by Race Fuels.
These things aren’t high tech and run a four-speed G-Force manual dog box and ‘Detroit Locker’ rear differential. The final drive ratio is set at 4.11:1 but the secondary gearset can be swapped quickly thanks to the Gleason quick change, allowing for easy customisation when running at Phillip Island one week, and our glamourous home track Wakefield the next.
The beauty really lies in the simplicity of these things, though, Tim managed a 1.01.00 at Wakefield Park, but these bulletproof Chevrolet motor is good for a couple of seasons without a rebuild.
SUSPENSION & BRAKES
Power is put through a juicy set of Hoosier 3045 Slicks mounted to 15x10 Basset steel wheels.
Behind these is a set of Wilwood GN6 calipers with a 12.19 inch rotor up front and Wilwood SL4 calipers on a 11.75 inch rotor in the rear.
Trans Am spec cars have ram forced front brake cooling and an in cabin brake bias adjuster.
Keeping the rubber on the ground are Penske 7500 series single way adjustable 7” shocks with a two-inch front sway bar is fitted. Spring rates are free for adjustment between (limited between 350-700 pounds in the front and 200-500 pounds in the rear)
INTERIOR
Tim is kept safe in the car by a (6 point, tower to tower cage built in house by Howe engineering) and a full containment racetech seat and racetech 6 point harnesses.
Vital data and lap timing is displayed to the driver by a Motec C127 7” digital dash. A switch panel to the right of the dash allows the driver to control brake fans, thermo fans, cool suit, trans pump etc. the cool suit and drink has been removed to get the Wall Racing 38 as close to minimum weight as possible.
Cover photo: Daniel Kalisz Photographer/ARG
You can keep up with Tims progress by the below links:
Tims 2021 calendar: https://www.tbmotorsport.com.au/2014-events
Tim Brook Facebook: https://www.facebook.com/timbrookmotorsport
Tim Brook Instagram: https://www.instagram.com/timbrook34/