efficiency of the RC truck's two-stroke engines. Explosive exhaust should go to the end of the tuned pipe and bounce back into the combustion chamber, stuffing exhaust back into the chamber to increase power. However, Terra Crusher's L-shaped manifold shape hampered the effectiveness of tuned pipe, further weakening the engine's performance. Legacy Tamiya recognized the flaws of Terra Crusher. Only a few months after the release of Terra Crusher, Tamiya released Wild Commando with smaller and lighter tires in the last quarter of 2002. This truck was identical to Terra Crusher, except for the lighter and smaller tires, an improved engine in the FS-18SR from the TNX and a new body. This alone reduced weight from and improved performance. The same small size tires were sold separately for Terra Crusher. However, the smaller tires that were better suited for on-road races were not popular for fans of Terra Crusher, who wanted a rugged off-road monster truck. The next model, TNX (TGM-03), was released in 2004. Its success proved that Terra Crusher's basic mechanical design was a very sound one. TNX is almost identical to Terra Crusher, aside from a few upgrades; notably stronger O.S designed 1.8 in³ (3 cm³, up from 2.5 cm³) glow engine, removal of electronics box and employing much lighter tires. TNX tires were smaller than Terra Crusher's but bigger than Wild Commado's tires, placing the truck back in the off-road category. The Terra Crusher's reverse gear had required delicate-tuning and was abandoned for the TNX. Terra Crusher's weight was reduced to for the TNX. With these modifications, the TNX quickly proved itself a very capable racing truck by winning numerous races. TNX 5.2R (TGM-04) is basically the same as the TNX, but mounts a larger and more powerful 5.2 cm³ engine, instead of the 3 cm³ engine. Aside from the engine upgrade, Tamiya made a few minor modifications to improve the truck's performance. Weight was further reduced to . The dual shocks were simplified to a single shock, and universal shafts were also simplified to the dog-bone type universals. The on-board starting system was abandoned for hand-held starting motor, which further saved weight. Released in 2007, Nitrage 5.2 is Tamiya's the most race worthy truck that was released in the summer of 2007. It uses the same 5.2 cm³ engine, but the truck is redesigned around 5.2 cm³ engine, geared toward adjustability of many parts for