In april 1989, the Tamiya Mud Blaster makes its debuts. It is the last model of the ORV (Off Road Vehicule) lineage which origins lead back to the 1983 Frog and the 1986 Blackfoot. Already considered as outdated when the model was released, this chassis will be used under a Subaru Brat bodyshell to create the Mud Blaster.
The red plastic chassis frame, borrowed from the Blackfoot, is made of two parts: once assembled, it is rock solid.
The electronics take place under the black cover: there you can find a front and reverse 3-speed mechanical speed controller.
Enclosed into the chassis frame, two servos lay side by side, one for steering and the other one to command the speed controller. Alike the Monster Beetle, an additional steel part is placed above the steering servo head in order to protect it from hits transmitted by the wheels.
Borrowed from the Frog, the front drivetrain has been modified with longer dampers and a specific higher shock tower on which lays the bodyshell. The stock Mud Blaster dampers are friction dampers: on this model, they were replaced with Tamiya constant volume hydraulic units (CVA).
A piano wire fixed onto the front bumper is used to guide and stiffen the front wheel arms. The nut on the upright side allows to change the play in the lower arm.
Also borrowed from the Frog, the rear drivetrain is of trailing arms type. The pretty uncommon position of the dampers proves they do not leak.
The rear transmission is made of a central plastic gearcase on which sides two steel plates are fixed to maintain the gears and the planetary differential. Dogbones are of hexa type and are protected into boots filled with grease.
There is only one possible gearing since the motor is mounted using a plate that only allows the use of a 10 teeth motor pinion. The battery door tray is fixed to the chassis and the gearcase, maintaining the battery pack transversally.
This model received several period options that make it more reliable: CRP 1618 reinforced uprights, CRP 3043 front reinforced plate, a specific CRP front bumper, CRP 1603 reinforced steering turnbuckles, CRP 1606 reinforcement for the rear arms, CRP 1608 differential bearing support, CRP battery door locker and a Thorp ball differential.
The full ABS bodyshell requires several hours of work if you want to follow the manual instructions. This bodyshell required over 20h of work from the raw ABS to the monograms and rims painting, including the application of the stickers.
With this model, Tamiya’s art was to adapt a japanese car to the Texas style. The high mounted bodyshell features a “cowboy” style and the big spike tires give it a “BigFoot” look.
On the track, the car handles like its predecessors. The high center of gravity requires to be careful when cornering at speed. The tires do a great dampening job in addition to the dampers, making the car clear any obstacle.
When accelerating, the rear drivetrain lowers and the car goes in straight line. With the Thorp differential, the transmission reveals to be bulletproof: no more worrying cracks can be heard when landing jumps. The stock servo-saver being quite weak, it was replaced with a Kimbrough unit that is more efficient and precise.
This is a model you are always pleased to drive, looking for reaching its limits and seeing it absorbing obstacles more or less bestially. But you must always keep in mind how many hours you spent working on the bodyshell: the ABS bodyshell can rapidly suffer from scratches.
I love this model because it is quite rare as collectors generally prefer the Monster Beetle and the Blackfoot. But this big wheel Subaru Brat version looks great.
Restoring this car, hunting for its rare options and decorating it as close as “box-art” as possible was a real pleasure, at least as intense as the result of watching it riding on the track.
David from RC4ON
More pictures in gallery : Tamiya Mud Blaster