M-03
The front-wheel-drive M-03 chassis is the logical evolution of the M-01 chassis. The M-03 chassis was released in 1998 and is the second front-wheel-drive chassis produced by Tamiya. Tamiya Engineering developed a chassis with a front-mounted 540 motor, monocoque frame and independent suspension on all four wheels with four dampers. There are three different wheelbases: M-03 with a short wheelbase of 210 mm, M-03M with a medium wheelbase of 225 mm and M-03L with a long wheelbase of 239 mm. The following models belong to this family:
Rover Mini Cooper Racing, model number 58211, released in 1998 and available on the market until 2010; model with M-03 chassis
Suzuki Wagon R RR, model number 58234, released in 1999 and available on the market until 2003; model with M-03 chassis
Toyota bB, model number 58265, released in 2000 and available on the market until 2003; model with M-03L chassis
Mini Cooper, model number 58295, released in 2002 and available on the market until 2008; model with M-03L chassis
Suzuki Swift Super 1600, model number 58368, released in 2006 and available on the market until 2012; model with M-03M chassis
MINI Cooper S 2006, model number 58400, released in 2006 and available on the market until 2007; model with M-03L chassis
Fiat 500, model number 58427, released in 2008 and available on the market until 2009; model with M-03M chassis
The M-03 chassis was developed in parallel with the TL-01 chassis, with which it shares several plastic parts, gears and performance-enhancing accessories. The main shared component is Part B, code number 50736: front and rear hubs with uprights and the servo arm for steering. In this section, the parts shown in bold in the image below on the left are used only in the TL-01 chassis and not in the M-03
The engineering of the M-03 chassis is the same as that of the TL-01 chassis; therefore, the chassis consists of two half-shells. The shock towers are an integral part of these half-shells, which is a flaw of the M-03 and TL-01 family because if the shock mount breaks, the chassis must be almost completely disassembled. Fiber plates from third-party suppliers are available on the market to reinforce the shock mounts and reduce breakage. However, this solution does not solve the problem.
The different wheelbases are achieved by adding two spacers, one on each side, between the front and rear sections of the chassis.
The spacers used to obtain the medium wheelbase chassis are F2 and F5 from part 51238 (first row of the image), while the spacers used to obtain the long wheelbase chassis are D3 and D4 from part 0005798 (second row of the image).
The three chassis exhibit different behaviors due to their varying wheelbases, as well as differences in weight distribution. In the image below, moving from top to bottom, the three installation instructions for the electronics from the M-03, M-03M and M-03L chassis manuals are shown respectively. When changing chassis type, the electronics are always installed in the same area of the rear section. Naturally, the center of gravity shifts depending on whether the chassis is short, medium, or long. Therefore, the electronics are positioned more or less close to the center of gravity depending on the chassis type.
Additionally, the manual suggests installing the receiver in the upper part of the chassis, raising the center of gravity. Tamiya achieves different wheelbases by inserting a section between the front and rear parts of the chassis. The long wheelbase chassis allows the use of the additional space to install electronics in the lower part of the chassis, lowering the car’s center of gravity: the receiver must be small enough to be installed in the central (spacer) section used to extend the wheelbase. With these variables, different road-holding behaviors can be achieved depending on the wheelbase and the electronics installation.
For this product family, Tamiya has alternatively provided the option to install a servo motor, a mechanical speed controller and an electrical resistor to regulate the speed of the electric motor. This system must be mounted at the rear of the chassis, which alters the weight distribution once again and therefore affects the handling of the chassis compared to configurations using an electronic speed controller.
List of accessory parts to enhance performance:
50473 – a high-torque steering servo saver
50684 – two 60D radial tires
The inner diameter of the 60D and 55D tires is the same, but the outer diameter differs; therefore, both 60D and 55D tires can be mounted on M-chassis wheels. With the same motor and motor speed controller, installing 60D tires results in a top speed 8–10% higher than the maximum speed achievable with 55D tires. Similarly, 55D tires provide an 8–10% improvement in acceleration compared to what can be achieved with 60D tires. The choice should be based on the track: 60D for fast tracks to increase top speed and 55D for twisty tracks where frequent acceleration is required. The performance difference depends on the different maximum radius of the two tire types.
50686 – four soft foam inserts for 60D tires (on the left in the images below)
53068 – Sport Tuner Electric Motor
53155 – two low-friction shock absorbers in lightweight alloy, shock body in pink color (center in the images below)
53056 – four alloy hex adapters for wheels (on the right in the images below)
53205 – pair of universal front drive shafts for M-Chassis (on the left in the images below)
53218 – pair of reinforced joints for the differential-side drive shafts
53254 – two Super Grip 60D radial tires
53255 – four standard foam inserts for 60D tires that strengthen the tire sidewall and reduce body roll
53267 – TA-03 ball differential set; Tamiya has never released a ball differential specifically designed for the M-03 chassis. The TA-03 ball differential is adjustable and lighter, resulting in smoother transmission depending on motor power and less rotating mass. Differential tuning is complex and the balls require very frequent maintenance. The stock gear differential is chosen for reliability and ease of use, while the ball differential is chosen for performance (center in the images below)
53301 – stainless steel suspension shafts for the four lower arms, two shafts per arm (on the right in the images below)
53303 – four adjustable upper suspension arms (on the left in the images below)
53308 – two aluminum towers for steering servo installation
53333 – six touring car springs (for short shock absorbers) with three stiffness levels: yellow, blue, red in increasing hardness. To balance the chassis and improve drivability, set the rear suspension softer than the front; for example, install “medium” springs at the front and “soft” springs at the rear (center in the images below)
53340 – two reinforced 60D type A tires for M-Chassis
53343 – front and rear stabilizer bars for M-03 (on the right in the images below)
53344 – heat sink for electric motor with two installation screws (on the left in the images below)
53345 – reinforced rear hub for M-03. Shared part with the TL-01 chassis (center in the images below)
53346 – quick-release battery holder. Shared part with the TL-01 chassis (on the right in the images below)
53348 – complete ball bearing set for M-03
53379 – lightweight balls for the differential (part number 53267)
53390 – hollow carbon gear shaft for M-03, guide for building carbon parts. Shared part with the M-04 chassis (on the left in the images below)
53435 – two shaped rubber inserts for 24 mm wheels (center in the images below)
53439 – anti-wear grease
53443 – three types of silicone shock oil: #200, #300, #400 (on the right in the images below)
53444 – three types of silicone shock oil: #500, #600, #700
53508 – lubricating oil for metal bearings
53509 – HFC 0.6 aluminum pinion gear (20T)
53523 – two aluminum front steering uprights for M-03. Shared part with the M-04 chassis (on the left in the images below)
53527 – two titanium turnbuckles 3×32 mm (center in the images below)
53571 – four low-friction lightweight alloy shock absorbers, TRF series; shock body in gold color (on the right in the images below)
54216 – two reinforced Super Grip 60D radial tires as an alternative to part number 53254
54277 – reinforced gear set (black color, stock gears are white)