This is the XRAY T4, 2013 EU Rubber-Spec Competition 1/10 Scale Electric Touring Car Kit. For almost a full year the XRAY Research and Development team has been designing and refining the T4 chassis. In total, 5 completely different prototype chassis were made and tested all around the world on a variety of surfaces and condition during that time. Whether it was carpet or asphalt, indoor or outdoor, hot or cold conditions, thousands and thousands of laps were run and countless amounts of data was recorded, evaluated and compared.
Of those prototypes, only the best ideas and parts were chosen to be incorporated into the final prototype. This prototype was then hard-core tested for several months by XRAY team drivers all around the world. The drivers all returned with the same results, feedback and conclusion: “This is the best performing, most innovative XRAY touring car that I have ever tested or driven.”
With a clear vision and mission in mind, the research team set out to accomplish five main design improvements on the T4:
- Lowered Platform
- Improved Chassis Flex
- Increased Traction
- Improved Steering Characteristics
- Improved Weight Balance
- Chassis: The T4 features a redesigned chassis specifically designed for all kinds of track conditions. The 2.2mm thick chassis is CNC-machined from premium-grade graphite material and provides maximum traction under low traction conditions while maintaining stability and forgiveness under high traction conditions. Weight distribution and balance characteristics have been enhanced. Due to the increase in LiPo capacity resulting in additional weight and heavier duty electronics to handle the increased power of modern brushless systems, the chassis was designed to allow the weight to move as close as possible to the chassis centerline in order to maintain balance. In addition, the bulkhead mounting holes were narrowed by 6mm to make the mounting points as narrow as possible for more traction and better balance. The front and rear portions of the chassis were strategically redesigned to provide maximum steering and traction. The chassis is an ultra-narrow 94mm wide and features pre-drilled holes for options such as: chassis weights, graphite motor guard and battery strap.
- Top Deck: The top deck has been redesigned for the narrow bulkheads. The shape of the rear portion of the top deck has been specifically designed to achieve maximum traction and in corner steering. The top deck is machined from premium-grade 2.0mm graphite. An optional belt tensioner can be mounted to the top deck.
- Super Low Profile (SLP) Shocks: T4 shock absorbers were completely redesigned and re-engineered. Everything is updated and the shocks are aluminum. The SLP shocks were developed to lower the CG of the car to the absolute maximum in order to improve stability. With the SLP shocks the T4 stays flatter, making it easier to drive in chicanes and more resistant to traction roll, letting you carry more speed through high traction sweepers. SLP shocks feature redesigned shock caps, shock collars, pistons, as well as all redesigned composite parts. The shocks also feature bladders and foam inserts for smoother shock operation. Shock rods have been especially hardened to ensure long life and maximum strength. Updated pistons were also designed and produced. The set of pistons include 3 and 4 hole pistons with 1.0, 1.1, and 1.2mm diameter holes. The pistons are molded using special methods and composites to ensure extreme roundness, while maintaining maximum stiffness and durability. The Super Low Profile shocks are almost 8mm shorter compared to the shocks on the T3. The shock bodies are CNC-machined from premium Swiss 7075 T6 aluminum and hardened to ensure maximum life. The shocks consist of a shortened shock body but with a larger diameter to retain the same volume of oil as the previous, longer T3 shocks.
- Super Short Shock Springs (4S): The 4S springs have been specifically designed to complement the SLP shocks and are 5mm shorter than previous XRAY springs. The T4 comes equipped with C2.7 linear springs in the front to provide maximum stability and steering and C2.3-2.6 progressive springs in the rear to provide maximum traction and cornering speed. The main advantage and benefit of progressive springs is that as the car initially enters the corner they work like a C2.3 spring to provide maximum traction. At the same time, when the chassis begins to roll, in the middle of the corner, the spring rate progressively increases until it works like a C2.6 which allows the car to maintain maximum cornering speed. The 4S springs, like all the other XRAY springs, are manually measured, selected and matched into pairs to guarantee precisely equal length and damping characteristics.
- Shock Tower: To maximize the effect of the SLP shocks, both front and rear shock towers were completely redesigned and lowered by 15mm to help move the CG as low as possible. Machined from premium-grade 3.0mm graphite, the shock towers are smaller, lighter, more compact and after vigorous testing, have been race-tuned to increase on-power steering.
- Aluminum Bulkheads: To accommodate the ultra-low design of the T4 platform with centralized weight placement, all the bulkheads were completely redesigned. These small and light bulkheads are positioned more to the chassis centerline to provide maximum traction, steering and balance. All bulkhead parts are CNC-machined from premium Swiss 7075 T6 aluminum and have been designed to provide the lightest and strongest possible support framework for the car. All 4 differential bulkheads now share a common design in order to reduce spare parts requirements and increase parts compatibility. The left and right layshaft bulkheads also share a common design and are interchangeable with one another. The bulkheads are anodized in a distinctive orange color. (Note: Color may vary slightly between products.) XRAY’s legendary attention to detail is noticeable in all the precisely chamfered edges.
- Motor Mount: The redesigned motor mount has been isolated from the layshaft bulkhead in order to eliminate unwanted tweak. The motor mount is fixed to the bulkhead by two screws and to the chassis via M3 nut providing the tweak free platform. Thanks to this unique design the motor mount has been moved 3mm closer to the chassis centerline, which increases stability and improve balance of the car. The motor mount is CNC-machined from premium Swiss 7075 T6 aluminum.
- Upper Bulkhead Clamps: To coincide with the super narrow bulkheads, the upper bulkhead clamps were also redesigned. With 3 different roll center mounting positions, adjusting the roll center of the chassis is quick and easy. The clamp height has been reduced by 2mm compared to the previous platform, which adds additional flexibility for roll center adjustments by allowing you to add or remove shims under the ball studs. In order to keep the same well-proven roll center geometry the roll center positions have been moved outside to offset the narrow bulkhead design.
- Bearing Holders: The adjustable bearing eccentric holders were also updated to mate with the narrower bulkheads. As with previous XRAY designs, both front and rear bulkheads feature integrated belt-tension adjustment through the use of adjustable bearing eccentric holders, eliminating the need for a separate belt tensioner while reducing friction and improving drivetrain efficiency.
- Suspension Mounts: The front and rear suspension holders are CNC-machined from premium Swiss 7075 T6 and are fully independent from the bulkheads and mounted directly to the chassis which increases traction and makes the car easier to drive. The front one piece holder has been updated to allow easier access to the steering rack to simplify Ackermann adjustment. The reinforced rear aluminum lower suspension holders are mounted to the chassis with two screws for extra strength and have been moved 0.75mm inboard to narrow the rear track width and provide more in corner steering.
- Central Servo Mount: XRAY’s own invented and designed central servo mount is now a standard in the T4. This style mount allows the servo to be mounted to the chassis without the servo coming into contact with the chassis plate. This design has been engineered to eliminate tweak and increase overall traction. The Swiss 7075 T6 main aluminum stand is positioned along the chassis centerline for perfectly balanced flex characteristics and holds the high-grade graphite servo plate suspended above the chassis.
- Steering Plate: To gain more steering and to improve the direction changes of the car, the steering plate was redesigned to move the connection of the servo linkage into the absolute center of the dual arm steering system and is CNC-machined from premium Swiss 7075 T6 aluminum. The steering plate also works as a mechanical stop for the steering throw, limiting the steering angle to 25 degrees in order to smooth steering response and maintain maximum corner speed.
- Servo Savor: The popular XRAY servo saver was improved and updated for the T4. To make the steering linkage adjustment easier additional positions on the servo saver were added. The servo saver consists of 4 springs which makes the servo saver strong enough to provide the precision steering racers demand, while at the same time being flexible enough to prevent servo damage in hard crashes. The servo saver has interchangeable bushings to fit most popular servos.
- Anti-Roll Bars: To accommodate the narrowed front and rear bulkheads, updated anti-roll bars were designed. Front 1.4mm and rear 1.2mm anti-roll bars are included in the kit, and a full line of optional anti-roll bars for super-fine tuning is available. For easy recognition the anti-roll bars have laser-engraved stripes (to indicate bar thickness) for easy and instant recognition. The anti-roll bars are mounted using the included composite holders on the front and rear bulkheads, and to the integrated anti-roll bar mounts on the suspension arms. The rear anti-roll bar mounting location was updated on the T4 and is now in a horizontal position for easier accessibility.
- Rear Uprights: To improve the stability of the car and to increase cornering speed of the T4 the hard "H" rear uprights are included. The rear uprights feature 0° toe to ensure stability and prevent suspension geometry changes in hard crashes. There are two different roll center positions on the rear uprights, and more roll center positions can be easily adjusted by adding shims between the upright and the turnbuckle ball joint. The rear uprights feature small but robust 5x10x4mm ball-bearings to minimize un-sprung weight. The rear uprights are available in two different material formulations that were specifically blended for particular racing conditions. Also available in medium “M” hardness as an option. 1-hole uprights were developed as an optional fine-tuning part to compliment the standard 2-hole uprights for high-traction tracks where more roll of the car is desired. These 1-hole uprights provide an additional option versus the standard 2-hole upright when the outer hole does not allow enough roll, and the inner hole creates too much roll.
- 50mm Rear Drive Shafts: The T4 features 50mm long lightweight aluminum drive shafts machined from premium Swiss 7075 T6, hard-anodized and black coated for stylish looks. The aluminum drive shafts are designed for use in the rear.
- Bumper: To improve the body fit as well to lower the CG an updated front from bumper was designed which is 1/3 lower and lighter and manufactured from highly resilient lightweight foam. The lower composite bumper mount and upper bumper holder are molded from rigid composite material to withstand heavy impacts. An optional stiffer foam bumper (XRA301225) as well as an impact-absorbing lower bumper mount (XRA301203) are available as option parts.
- XRAY Gear Differential: The T4 gear differential increases on-power steering which is needed on nearly all types of tracks, and is ideal for both carpet and asphalt tracks. The gear differential includes a composite case and cover with pulley. Differential gears are made from tough composite material, precision-molded composite gears combined with light aluminum drive shafts, which create a lighter and super-smooth gear differential. Another key advantage of the gear differential is that it is maintenance-free. When the differential is correctly built, there is no need for maintenance for a very long time… no need for frequent oil changes, and no leakage due to the superior sealing system.
- XRAY Solid Axle: Rotating mass is one of the most significant influences on the performance of an RC racecar. The T4 features a unique lightweight composite XRAY Front Solid Axle. The Front Solid Axle has a very stiff and ultra-light weight structure that was achieved by molding the entire solid axle from XRAY’s own self-formulated composite material. Outdrives are fully exchangeable which allows very easy and comfortable servicing, while the unique drive shaft connection — eliminating the former drive shaft blades — enables direct power transfer to the axle and eliminates play between the drive shaft and outdrives, improving steering precision and increasing overall steering.
- Drivetrain: The ultra-efficient and well-proven drive train has been carried over from the T3 platform. The drive ratio is fully suitable for the current high performance brushless motors (both stock and mod) and LiPo batteries. Both the front solid axle and the rear gear differential feature 38T pulleys and the central layshaft features 20T pulleys for an efficient internal ratio of 1.9.
- Integrated Belt Tension Adjustment: As with previous XRAY cars, both front and rear bulkheads feature integrated belt-tension adjustment through the use of adjustable bearing eccentric holders, eliminating the need for a separate belt tensioner. These eccentric holders were modified to fit the super narrow position of the bulkheads, while allowing you to still use your existing differentials and spools. All ball-bearings turn in composite hubs to reduce friction and improve drivetrain efficiency.
- Differential Height Adjustment: Both front and rear bulkheads feature independent differential height adjustment. By rotating the differential eccentric holders, the height of the differentials can be adjusted by 1mm. Optional eccentric holders with 2mm offset are available which allows differential height adjustment of 2mm.
- Centrally-Positioned Layshaft: The spur and pinion gears have been aligned along the absolute centerline of the chassis to optimize the placement of the polar moment and ensuring ideal balance of the drivetrain components.
- Aluminum Middle Layshaft: The aluminum layshaft is strategically CNC-machined to minimize rotating weight without compromising strength or integrity. The hollow layshaft is perfectly round with zero run out, eliminating drivetrain vibration and producing a positive balance. Composite pulleys key solidly to the layshaft.
- Premium Ball Bearings: A full set of 20 high-speed, blue-sealed ball-bearings are used throughout the drivetrain to ensure maximum efficiency. All of the bearings are degreased and oiled with Aero Shell Fluid 12 for maximum smoothness and long life. The bearings used in steering blocks and uprights have been specially selected to reduce un-sprung weight and maximize drivetrain efficiency.
- Kevlar Drive Belts: The 2-belt 4WD drivetrain concept provides maximum efficiency and highest performance using Kevlar-reinforced drive belts for ultra-high durability. Narrow (3mm) front and rear drive belts have been ground to minimize thickness and flexibility.
- HUDY Spring Steel CVDs: T4 constant velocity drives (CVDs) are exclusively manufactured from special world-renowned, top-secret, self-developed HUDY Spring Steel. The drive shafts are the world‘s tiniest yet most durable drive shafts used in electric touring cars. The drive shafts are strategically lightened to guarantee the lowest possible weight without compromising strength or durability. These specially-lightened drive shafts can only be manufactured from special HUDY Spring Steel which was developed for extreme racing conditions. The drive shafts have been additionally hand-ground for maximum precision and to provide true rotation and unbinding drivetrain operation.
- Super-Lightweight Drive Axles: To reduce rotating weight, the T4 features super-lightweight wheel axles which have the outer diameter specially ground to remove the material while keeping the same strength thanks to the use of HUDY Spring Steel material. The lightweight drive axles reduce rotating mass up to 35% compared to regular drive axles.
- Suspension Holders: The T4 uses the same smart suspension holders as the T3 platform. The aluminum inserts in the composite holders guarantee that geometry and setup will not change and will be retained even after hard crashes. There are 3 different suspension composite holders that enable easy roll center setup. The standard suspension holder gives a 0mm roll center, while two eccentric suspension holders raise or lower the roll center by 0.75mm. The independent suspension holders of the T4 allow for even more precise roll center adjustment. The suspension holders — which are mounted on separate bulkheads — may be shimmed outward from the bulkheads (using 0.1–0.5mm shims) for precise roll center positioning. The smart XRAY geometry uses variable-thickness shims between the bulkheads and suspension holders to enable easy rear toe-in adjustment. However, you can easily remove the shims which will narrow the suspension, and then add wheel offset shims to reclaim track-width.
- Proven Suspension Geometry: From the narrow arms, through the tiny front and rear suspension blocks, to the small and robust steering blocks, every suspension part has been specially designed to provide responsive racing characteristics in all racing conditions. The T4 platform features optimized suspension parts carried over from the T3platform. The arms feature a single optimized shock mounting position and integrated anti-roll bar mounts. The rear arms feature three anti-roll bar mounts for super-fine adjustment of the anti-roll bar.
- C-Hubs: The C-hubs in the T4 are also carried over from the T3 platform and feature large openings for quicker and easier assembly and disassembly of the CVDs. The entire CVD assembly can be easily inserted/removed through the C-hub without the need for disassembly. The large openings prevent collision of CVD with C-hub in serious crashes and are optimized for use with optional ECS drive shafts. The C-hubs are available in all standard caster angles (2°, 4°, 6°) and are also available in two different hardnesses that are optimized for particular racing conditions.
- Steering Blocks: The small and tough steering blocks each feature two Ackermann positions. The front steering blocks also feature small but robust 5x10mm ball-bearings to minimize un-sprung weight. The steering blocks are available in two different hardnesses, which are optimized for particular racing conditions.
- Dual Arm Steering System: The dual arm steering system is supported by 6 ball bearings and runs on aluminum stands. Ackermann is easily adjusted by inserting shims between the steering plate and steering rods. The steering system features a lower mounting position for steering linkage which makes the car handle easier going into corners. Handling is easily adjusted for more aggression by inserting a shim between the steering block and steering rods. The front lower suspension holder has been updated to allow easier access from the front of the car for quick and easy Ackermann adjustment.
- Aluminum Hex Hubs: Ultra-lightweight wheel hex drive hubs are CNC-machined from 7075 T6 black-coated aluminum. These ultra-true hex hubs are specially machined to reduce rotating weight while guaranteeing wobble-free wheel mounting. Optional offsets are available (-0.75, +0.75, +1.5mm).
- Aluminum Turnbuckles: Aluminum adjustable turnbuckles used in the T4 are CNC-machined from 7075 T6 material with a stylish black coating. These turnbuckles are used for front and rear upright linkages as well as for the servo saver. The aluminum turnbuckles are lighter than steel to help decrease the overall weight of the car.
- Body Posts: Beefy 6mm thick body posts are made from special composite material that provides maximum strength but sufficient flex to reduce body post breakage in hard crashes or if you flip the car over. The body supports are rounded to have a better fit and provide better support to the car body. For ultimate tuning and adjustment, XRAY offers optional body height adjustable body posts which allow the independent front and rear body height adjustment by +1mm or +2mm.
- Battery Holders: Smart battery holders are specifically designed for LiPo batteries and are reinforced for higher impacts. The battery holders prevent the batteries from moving under racing conditions and crashes.
- Adjustment Possibilities: The extensive and impressive range of adjustment possibilities includes: caster, camber, toe, anti-dive, anti-squat, ride height, downstops, track-width, lower roll center, upper roll center, roll center positions, steering roll center, wheelbase, Ackermann, optional belt-tension adjustment, adjustable shocks, adjustable rear diff and adjustable optional front XRAY Multi-Diff.
- Chassis Balance: The chassis design focuses on balanced weight distribution and weight transfer. The chassis features pre-drilled holes for additional weights for optimum car balancing. Centerline holes are pre-drilled for easy balancing with the HUDY Chassis Balancing Tool (HUD107880).
- Graphite Grease: The T4 includes premium HUDY Graphite Grease which is a high-performance, advanced-technology semi-fluid lubricant which incorporates both extreme pressure additives and finely-dispersed graphite for load carrying. It is intended primarily for the lubrication of rotating parts and loaded gears. In addition to providing outstanding load carrying, it is formulated to have excellent adhesion and resistance to "fling-off" under extreme conditions. The grease reduces wear and increases parts life.
- Completely redesigned T4 platform
- Designed for highest performance at all levels of racing, with specific attention paid to the smallest details
- Thinner 2.2mm graphite chassis designed for increased traction, steering, stability, and improved cornering speed
- Redesigned graphite top deck for increased in-corner steering and traction
- Redesigned super low profile shock towers to lower the CG and improve stability of the car
- Redesigned SLP (super low profile) aluminum shocks to further lower the CG and improve stability of the car
- Redesigned 4S shock springs developed & designed for the SLP shocks
- Redesigned bulkheads, lightened and strategically placed closer to the center of the chassis to provide more steering and traction for the car
- Redesigned super low profile motor mount machined separately from layshaft bulkheads and featuring a tweak free mounting system
- Redesigned upper bulkhead clamps designed for the super narrow placement of the bulkheads
- Redesigned front aluminum lower suspension holder designed for easier access for Ackermann adjustments
- Redesigned rear aluminum lower suspension holders, redesigned for increased durability and moved closer to the chassis centerline to increase steering
- Redesigned aluminum steering plate for dual arm steering system with central mounting of the steering linkage
- Redesigned servo mounting system for improved balance and for elimination of unwanted tweak
- Redesigned servo saver with additional positions for servo linkage mounting
- Redesigned anti roll bars revised to fit super narrow bulkheads
- Redesigned rear uprights from hard material for increased stability of the car
- Redesigned composite hubs for differentials to fit super narrow bulkheads
- Redesigned front body mounts shortened to lower CG
- Redesigned low profile foam bumper to lower CG
- Redesigned race tested and tuned shock positions
- Redesigned rear 50mm drive shafts
Class: 1/10 electric touring car
Width: 189mm (Adjustable)
Wheelbase: 256-261mm (Adjustable)
Weight: 481 grams
Ready-to-run Weight: approx. 1377 grams
Needed To Complete:
- 2-Channel Radio System
- Steering Servo
- Electric Speed Control
- Motor Pinion
- Lipo Battery & Compatible Charger
- Tires, Wheels & CA Glue
- 190mm TC Body & Polycarbonate paint