{"product_id":"tam42391","title":"Tamiya TRF421X 4WD Electric Touring Car Chassis Kit - 1\/10 Scale Competition Limited Edition","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThe Tamiya TRF421X Chassis Kit represents the pinnacle of Tamiya Racing Factory engineering—the most advanced racing chassis ever developed by TRF. Unveiled as the sensation of the 2026 Toy Fair competition category, this successor to the acclaimed TRF421 is packed with new and improved features directly derived from TRF racing team experience at international events including the IFMAR ISTC Worlds. Every detail has been scrutinized and improved to deliver world-class touring car performance.\u003c\/p\u003e\n\u003cp\u003eBuilt on a brand-new 2mm thick aluminum chassis, the TRF421X features a proven 2-belt drive system with numerous refinements. The motor position is now even lower thanks to a new motor mount, front and rear wishbones are made of carbon fiber reinforced plastic for superior stiffness, and the damper positions are flatter to accommodate the latest hypercar bodies. With updated suspension geometry for higher cornering speeds, ball bearing driveshafts, and an expanded range of tuning options, the TRF421X sets a new benchmark for competitive touring car racing.\u003c\/p\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1\/10 scale competition touring car chassis assembly kit\u003c\/li\u003e\n\u003cli\u003eBrand-new 2mm thick aluminum chassis with optimized flex characteristics\u003c\/li\u003e\n\u003cli\u003eLowered motor position (1.04mm lower than TRF421) for reduced CG\u003c\/li\u003e\n\u003cli\u003e2-belt drive 4WD system with proven efficiency\u003c\/li\u003e\n\u003cli\u003eCarbon fiber reinforced plastic (PA-CF) front and rear wishbones\u003c\/li\u003e\n\u003cli\u003eBall bearing type driveshafts for improved efficiency\u003c\/li\u003e\n\u003cli\u003eTwo different upper decks included (one-piece and split)\u003c\/li\u003e\n\u003cli\u003eNew adjustable center mount with sleeves, shims, and titanium screws\u003c\/li\u003e\n\u003cli\u003eFlatter damper positions for low-profile hypercar bodies\u003c\/li\u003e\n\u003cli\u003eTRF dampers with hard red springs included\u003c\/li\u003e\n\u003cli\u003eUpdated steering geometry for higher cornering speeds\u003c\/li\u003e\n\u003cli\u003eMultiple anti-roll bars included (2x 1.2mm, 1x 1.3mm)\u003c\/li\u003e\n\u003cli\u003eBalance weights for battery and receiver areas\u003c\/li\u003e\n\u003cli\u003eAll aluminum parts in signature TRF blue anodized finish\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003ePerformance Benefits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLower center of gravity from repositioned motor\u003c\/li\u003e\n\u003cli\u003eImproved traction from new suspension components\u003c\/li\u003e\n\u003cli\u003eHigher cornering speeds from optimized steering geometry\u003c\/li\u003e\n\u003cli\u003eBall bearing driveshafts reduce friction and increase efficiency\u003c\/li\u003e\n\u003cli\u003ePA-CF wishbones offer superior rigidity over glass fiber versions\u003c\/li\u003e\n\u003cli\u003eExtensive flex tuning via multiple top deck and center mount options\u003c\/li\u003e\n\u003cli\u003eRear center stiffener\/flex brace for fine condition tuning\u003c\/li\u003e\n\u003cli\u003eAlignment pins on motor mount and bulkheads ensure precision\u003c\/li\u003e\n\u003cli\u003eCompatible with TRF421 suspension components for expanded tuning\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUsage Notes\u003c\/h3\u003e\n\u003cp\u003eDesigned for competitive on-road touring car racing on high-grip carpet and asphalt surfaces. The TRF421X is optimized for experienced racers competing at club, national, and international levels. The chassis offers exceptional tunability for varying track conditions through extensive setup options. While focused more on performance than the 421, it remains accessible and easy to work on. Recommended for experienced builders and racers. Body, wheels, electronics, and motor sold separately.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical Specs\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eScale:\u003c\/strong\u003e 1\/10\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrive:\u003c\/strong\u003e Belt-driven 4WD (2-belt system)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChassis:\u003c\/strong\u003e TRF421X\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChassis Material:\u003c\/strong\u003e 2mm aluminum\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSuspension Arms:\u003c\/strong\u003e Carbon fiber reinforced plastic (PA-CF)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDampers:\u003c\/strong\u003e TRF aluminum oil-filled with hard red springs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDriveshafts:\u003c\/strong\u003e Ball bearing type (1.5x4mm bearings)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUpper Deck:\u003c\/strong\u003e Two versions included (one-piece and split)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnti-Roll Bars:\u003c\/strong\u003e 2x 1.2mm, 1x 1.3mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearings:\u003c\/strong\u003e Full ball bearings throughout\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVehicle Type:\u003c\/strong\u003e Competition touring car\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Tamiya Racing Factory\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eItem Number:\u003c\/strong\u003e 42391\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eComplete unassembled TRF421X chassis kit\u003c\/li\u003e\n\u003cli\u003e2mm aluminum chassis plate\u003c\/li\u003e\n\u003cli\u003eOne-piece upper deck\u003c\/li\u003e\n\u003cli\u003eSplit upper deck\u003c\/li\u003e\n\u003cli\u003ePA-CF front and rear suspension arms\u003c\/li\u003e\n\u003cli\u003eBall bearing type driveshafts\u003c\/li\u003e\n\u003cli\u003eTRF aluminum oil-filled dampers with hard red springs\u003c\/li\u003e\n\u003cli\u003eFront and rear stabilizers\u003c\/li\u003e\n\u003cli\u003eAnti-roll bars (2x 1.2mm, 1x 1.3mm)\u003c\/li\u003e\n\u003cli\u003eCenter mount hardware (sleeves, shims, titanium screws)\u003c\/li\u003e\n\u003cli\u003eRear center stiffener\/flex brace\u003c\/li\u003e\n\u003cli\u003eBalance weights (battery and receiver area)\u003c\/li\u003e\n\u003cli\u003eComprehensive instruction manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eNeeded to Complete\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1\/10 touring car body shell\u003c\/li\u003e\n\u003cli\u003eTouring car wheels and tires\u003c\/li\u003e\n\u003cli\u003e2-channel radio system (transmitter and receiver)\u003c\/li\u003e\n\u003cli\u003eLow-profile steering servo\u003c\/li\u003e\n\u003cli\u003eElectronic speed controller (ESC)\u003c\/li\u003e\n\u003cli\u003eBrushless motor\u003c\/li\u003e\n\u003cli\u003eLiPo battery pack\u003c\/li\u003e\n\u003cli\u003eCompatible battery charger\u003c\/li\u003e\n\u003cli\u003eBasic assembly tools\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSummary\u003c\/h3\u003e\n\u003cp\u003eThe Tamiya TRF421X represents the ultimate expression of Tamiya Racing Factory engineering for competitive touring car racing. With its lowered motor position, carbon fiber reinforced suspension arms, ball bearing driveshafts, and extensive tuning options, this chassis delivers world-class performance for serious racers. The signature blue anodized aluminum parts, dual upper deck options, and proven 2-belt 4WD system make this the definitive choice for competitors seeking the best from TRF.\u003c\/p\u003e","brand":"Tamiya","offers":[{"title":"Default Title","offer_id":50961812324658,"sku":"TAM42391","price":891.8,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0577\/9980\/2927\/files\/tam42391.jpg?v=1773062771","url":"https:\/\/rchopupparts.com\/products\/tam42391","provider":"RC Hop Up Parts","version":"1.0","type":"link"}