ARC R8.4E 1:8 Electric Onroad Car
ARC has announced their latest 1:8 Electric Onroad Racing car, the R8.4E. The R8.4E will be available in 2 different configurations- the R8.4EL and R8.4ES. While both cars feature specially designed 5mm carbon chassis for electric racing, the key difference is in their transmission and battery layout. The R8.4EL is designed to run either standard or shorty LiPo batteries, while the R8.4ES is designed to run exclusively with shorty LiPo batteries. For added tune ability, theR8.4E features adjustable front and rear suspension arm lengths and roll centre via changing the pivot pin inserts. Racers can choose from 3 different front low and upper arms length. The rear low arm roll centre can settle in middle or low and rear upper arm lengths also can be adjusted. The default setup places the front lower arms in the centre – with a longer front low arm can generating more traction while a shorter arm delivers better steering response.
The suspension arms of the R8.4E are all new shape and material, The new suspension arms are designed with lighter weight and more flexibility, There are 3 different hardness of the R8.4E suspension arms, the Hard compound with H sign and the Soft compound with S sign, the default standard arms are without sign, the standard arms work well at most tracks, Hard arms can provide more consistent handling in all condition, The Soft arms work well especially in the cold and low grip tracks.
On both the R8.4EL and R8.4ES, the motor bulkhead and main-shaft bulkhead have been integrated into a single unit. The new bulkhead design reduces vibration between the pinion and spur gears, resulting in improved drive train smoothness, efficiency and improved durability to the pinion and spur gears.
While both cars feature 3-belt transmission systems, the R8.4EL places all 3 belts along the centreline. Meanwhile the R8.4ES features a similar belt layout to the R8.4 nitro car, with the side belt moving to the left side to allow the batteries to be placed in the centre. Both R8.4EL and R8.ES cars use the same belts and pulleys with the drive ratio being the same.
The front and rear uprights on the R8.4E are designed with eccentric inserts. This allows the axle height and direction to be changed for fine tuning the wheelbase and roll centre. Both uprights can use big (12x21mm) and small (12x18mm) ball bearings with insert.
The optional wheel disks are available for both front and rear upright, the wheel disk can reduce the turbulence inside the rim can improve the stability, especially in high-speed corners.
The main difference between R8.4EL and R8.4 ES is the weight distribution and the resulting handling characteristics.
R8.4EL (Standard LiPo): Front 48% / Rear 52%.Approx. weight: 2330g
R8.4EL (Shorty LiPo): Front 46% / Rear 54%.Approx. weight: 2190g
R8.4ES: Front 45% / Rear 55%.Approx. weight: 2170g
R8.4 (Nitro): Front 44% / Rear 56% Approx. weight: 2280g
While the shorty equipped R8.4EL can have almost the same weight distribution as R8.4ES, But the R8.4ES places its motor and batteries closer to the centre line of the car and it delivering similar handling characteristics to the R8.4 Nitro.
With the R8.4E, ARC introduces new 13mm big bore shocks to its 1:8 platform. 13mm bore shocks have been successfully utilised in our 1:10 electric cars for a number of years. With its larger 13mm bore, they hold a larger volume of silicon oil which improves consistency and reduces maintenance. The shock height has been lowered and positioned further outboard, delivering significantly improved steering response and corner speed to the R8.4E. A new big bore spring set features 20mm front springs with 5 different hardness from C7.6 to C9.9, and 25mm rear springs with 4 different hardness from C6.5 to C7.7.All springs are finished in a black coating with coloured markings for easy identification.
Source: Team Titan [team-titan.com.tw]
