Toyota’s new conventional and hybrid powertrains for 2018 Camry deliver significant boost in efficiency
22 June 2017
The 2018 Toyota Camry, the new eighth-generation of the most popular mid-size sedan in the world and the best-selling car in America for the past 15 years, will be going on sale in the US in late summer. Toyota unveiled the 2018 Camry at the North American International Auto Show (NAIAS) in January. (Earlier post.)
The new Camry is based on the TNGA (Toyota New Global Architecture) (earlier post), manifested with the use of the GA-K platform. Along with the new platform, an all-new 2.5-liter four-cylinder Dynamic Force Engine, new Direct Shift-8AT eight-speed automatic transmission and a new double wishbone rear suspension design are all representative technologies that have evolved through TNGA.
|2018 Toyota Camry Hybrid XLE. Click to enlarge.|
Through TNGA, the Camry now has an ideal driving position for the driver—allowing for better concentration on the road ahead while helping to reduce driver fatigue—along with improving the overall seating position for all the vehicle’s occupants. Due to these changes, plus the reconfigured lower beltline height and the more integrated design of the instrument panel, the driver and front passenger will experience more expansive outward visibility. Lateral visibility for the driver is enhanced, thanks to a repositioning of the A-pillars and side view mirrors; this design reconfiguration further aids the sense of openness for both the driver and the front passenger.
Powertrains. Three new powertrains will be available on the new 2018 Camry: They include the all-new 2.5-liter inline-four-cylinder D-4S gasoline engine and a new 3.5-liter V6 with D-4S Fuel Injection, both of which are paired to a new eight-speed Direct-Shift automatic transmission (8AT); and a next-generation Toyota Hybrid System (THS II).
2.5L Dynamic Force engine. Providing high power output with smooth and highly refined operation, the Camry’s new 2.5-liter four-cylinder Dynamic Force Engine has outstanding combustion efficiency.
This new powerplant incorporates an array of Toyota’s most advanced technologies including Dual VVT-i with VVT-iE (Variable Valve Timing intelligent system by Electric motor), D-4S (Direct injection 4-stroke gasoline engine Superior version) direct injection and laser-clad valve seats for optimal power production, emissions performance and fuel efficiency.
With its long-stroke and high compression ratio, multi-hole direct fuel injectors, variable cooling system and VVT-iE, this high-output powerplant takes the gasoline-powered internal combustion engine to an increased level of thermal efficiency.
The engine features VVT-iE on the intake side while utilizing VVT-i (Variable Valve Timing with intelligence) for the exhaust, a highly efficient compression ratio of 13:1 (14:1 for the hybrid version) for increased thermal efficiency and fuel efficiency and a bore and stroke measuring 3.44 inches and 4.07 inches, respectively; the stroke has been increased from the previous 3.86 inches to achieve the higher compression ratio.
Peak horsepower is estimated at 206 at 6,600 rpm (176 horsepower at 5,700 rpm in the hybrid configuration) with torque estimated at 186 lb-ft (252 N·m) at 5,000 rpm (163 lb-ft (221 N·m) at 3,600-5,200 rpm for the hybrid). Fuel economy is rated at an EPA-estimate of 29 mpg city/41 mpg highway/34 mpg combined), a 26% improvement for combined mpg over the previous model.
The innovative Dual VVT-i with VVT-iE variable valve timing system uses an electric motor instead of oil pressure to control variable valve timing, helping the system enhance fuel efficiency with cleaner exhaust emissions—even when operating in cold temperatures or at low RPMs.
Utilizing a combination of both higher-pressure direct fuel injection (DI) and lower-pressure port fuel injection (PFI)—controlling the appropriate fuel injection method in accordance with certain driving/operational conditions—and new multi-hole (six per injector) nozzle direct injectors further elevate both fuel economy and power production.
Other important new technological innovations for the 2.5-liter 4-cylinder Dynamic Force Engine include a variable cooling system, full variable oil pump and a cooled Exhaust Gas Recirculation (EGR) system.
3.5-Liter V-6. Like the 2.5-liter inline 4-cylinder Dynamic Force Engine, the Camry’s newly-developed 3.5-liter V-6 is equipped with the highly-advanced D-4S direct injection system, along with a specially-developed new VVT-iW (Variable Valve Timing-intelligent Wide) variable valve timing system. With the addition of these highly efficient engine technologies, it delivers higher power output, and class-leading fuel efficiency.
The 24-valve DOHC 3.5-liter V-6 engine employs the VVT-iW system for the intake, with VVT-i (Variable Valve Timing - Intelligent) on the exhaust, an efficient 11.8:1 compression ratio and a more squared bore and stroke of 3.70 inches and 3.27 inches, respectively, in comparison to the longer stroke of the Camry’s new 2.5-liter inline 4-cylinder power plant.
Power output is rated at 301 horsepower at 6,600 rpm and a torque rating of 267 lb-ft (362 N·m) at 4,700 rpm. Despite its power output, the new 3.5-liter V-6 engine achieves an EPA-estimated rating of 22 mpg city/33 mpg highway/26 mpg combined, an increase of 8% for combined mpg over the previous V6.
The V-6’s VVT-iW variable valve timing system has been engineered to ensure high torque production at all engine speeds. It utilizes the Atkinson cycle to enhance fuel economy without sacrificing performance or engine start ability at extremely low temperatures as well as in wide-open throttle (WOT) engine operation. Fuel efficiency is further enhanced by decreasing pumping losses from the delayed closing of the intake valves.
Direct shift 8AT. Both the 2.5-liter 4-cylinder Dynamic Force Engine and the 3.5-liter V-6 are equipped with the new Direct Shift 8-speed automatic transmission that allows the driver to freely experience the direct and impressive acceleration capability of the engines, along with the crisp-yet-smooth, quick-shifting capability of a performance-oriented gearbox.
The unit’s gear ratios have been carefully selected for enhanced power delivery as well as optimal fuel efficiency, with the mid-range gears utilizing close ratios to improve passing power.
The new gearbox also includes a torque converter that offers a wider range of lock-up (when compared to the previous 6-speed automatic transmission) for a more direct driving feel while contributing to improved fuel efficiency through suppressed engine revving.
Other features engineered into this 8-speed automatic transmission include new control logic, for more precise matching of engine torque, and smoother transitions when downshifting.
Toyota Hybrid System. Like the new Camry’s conventional gasoline powertrain, the new Toyota Hybrid System (THS II) has been engineered to provide spirited performance and driving enjoyment—including new Sequential Shiftmatic technology that allows the driver to “shift” the continuously-variable transmission (CVT), mimicking a quick-shifting six-speed automatic transmission via paddle shifters (on SE grade) or with the console-mounted shift lever while simultaneously achieving an optimal balance between high power output and energy efficiency.
The 2018 Camry Hybrid is available in three grades, LE, SE, and XLE. In addition to its enhanced handling and driving performance, the hybrid version of the new Camry achieves a best-in-class EPA-estimated mpg of 51 city/ 53 highway/52 combined on the LE grade—an impressive 30% increase for combined mpg—and 44 city/47 highway/46 combined on the SE and XLE, reflecting an increase of 21% for combined mpg.
Dynamic performance is delivered via the optimal control of the engine working in concert with the electric motor (MG2), while exemplary energy efficiency is achieved by using both electric motors (MG1 and MG2) for hybrid battery charging.
Driving characteristics and trunk room are improved through the implementation of the new TNGA packaging as it allows for the hybrid system’s battery pack to be moved from the trunk area to beneath the rear seat, positioning the battery weight at a lower center of gravity axis.
The updated Power Control Unit (PCU) of the new hybrid system plays a key role in improving the operational efficiency of this powertrain.
The improvements in the conversion efficiency of the PCU and the transaxle/electric motor combine to reduce energy loss by a total of approximately 20%. Additionally, improvements to cooling system efficiency has reduced energy loss by about 10%.
Just as in the Prius, the PCU is lighter and more compact as a result of integrating microcontrollers and using a new power stack structure, allowing the unit to be packaged directly above the transaxle. This new design lowers the vehicle’s overall center of mass and allows for a lower hood height.
Another key change to the PCU is a revised DC-DC converter (converts a source of direct current from one voltage level to another) that sees its control output optimized—including the conversion to AC power—helping to reduce the vehicle’s overall power consumption. Additionally, the output filter for the DC-DC converter has been redesigned so that it is more dimensionally compact (improved packaging/weight savings) and produces less noise (reduced NVH).
The 2018 Camry Hybrid is equipped with a Lithium-ion (Li-Ion) battery pack on the LE grade and Nickel-Metal Hydride (Ni-MH) battery pack on the SE and XLE.
Along with the traditional Camry Hybrid system drive modes of NORMAL, ECO and EV, a new SPORT drive mode setting has been added that allows for an increase in power from the hybrid system for improved acceleration response relative to pedal input. The NORMAL, ECO, and SPORT modes can each be used while EV mode is activated.
The Camry Hybrid also features the new Auto Glide Control (AGC), which helps to improve fuel efficiency by calculating an efficient coasting logic. When driving normally, engine braking will slow the vehicle down when the driver lifts off from the accelerator pedal. However, to avoid aggressive engine braking, AGC limits the loss of vehicle speed through an automatic drive setting that acts more like a neutral gear, allowing the vehicle to coast to the stoplight.
An AGC indicator light is illuminated on the Multi-Information Display (MID) when AGC is in operation to alert the driver that less deceleration torque than normal is currently being used. Of note, AGC can only be activated when the vehicle is being operated in the ECO drive mode setting.
Rigid body/platform. The new Camry provides a high-quality comfortable and stable ride manner with superior handling characteristics using a lightweight, high-rigidity body/platform structure with a 30% increase in torsional rigidity.
Despite the increased use of high-tensile-strength sheet metal and hot stamping materials resulting in a lightweight body, further weight reduction has been achieved through the use of an aluminum hood, while new construction techniques have led to the use of thinner body panels for the roof, hood, trunk lid, front and rear doors and front fenders when compared with the previous model.
Laser Screw Welding (LSW) has been incorporated at key junctures throughout the body/platform for increased joint rigidity.
A special high-rigidity urethane adhesive has been applied to both the windshield and rear window where it meets the vehicle body that helps to realize increased body rigidity.
The fortified body includes additional gussets for the front/rear door frame (B-pillar) that have greatly increased the frame/joint strength.
Also, the front suspension tower brace embedded within the cowl body now makes use of a closed cross-section construction, further advancing the vehicle’s dynamic handling prowess and stability in the corners. At the rear of the vehicle, a new rear body frame of annular construction enhances structural rigidity, joined by additional braces added to the rear suspension that can withstand higher levels of lateral force and increase the vehicle’s lateral rigidity.
Toyota engineers incorporated a variety of new noise, vibration and harshness (NVH) countermeasures that were previously found exclusively on luxury models. These include sound absorbing/insulation through the fitment of a hood insulator and upper and lower fender separator. The passenger compartment is further insulated from the engine and road noise using foam/vibration dampening materials throughout the vehicle along with a thicker dash silencer mat across the entire interior firewall section.
Furthermore, a special vibration-damping coating has been applied over a wider area of the underfloor, joined by noise-proofing material encompassing more surface area of the interior’s ceiling. Wind noise has been suppressed through a newly-designed rain gutter molding and a reduction in the step at the bottom of the windshield.
Toyota Safety. Among the many features on the 2018 Camry is the standard Toyota Safety Sense P (TSS-P) suite of safety systems and technologies. This multi-feature advanced active safety suite bundles cutting edge active safety technologies including Pre-Collision System with Pedestrian Detection (PCS w/PD), Dynamic Radar Cruise Control (DRCC), Lane Departure Alert with Steering Assist (LDA w/SA); and Automatic High Beams (AHB). Select models will also come with standard Blind Spot Monitor (BSM) with Rear Cross Traffic Alert (RCTA). The available Intelligent Clearance Sonar (ICS) also includes a new Rear Cross Traffic Braking (RCTB) system.
All 2018 Camry’s have 10 standard airbags and Toyota’s Star Safety System, which includes Enhanced Vehicle Stability Control, Traction Control, Electronic Brake-force Distribution, Brake Assist, Anti-lock Braking System, and Smart Stop Technology. All Camry’s also come equipped with a standard backup camera.
Pricing. The manufacturer’s suggested retail price (MSRP for the new 2018 Toyota Camry gasoline models will range from $23,495 for the value-driven L grade 4-cylinder to $34,950 for the Premium XSE V6. The MSRP for the Camry hybrid will range from $27,800 for the LE to $32,250 for the XLE.
The MSRP for the Camry does not include the delivery, processing, and handling (DPH) fee of $885. The DPH fee for vehicles distributed by Southeast Toyota (SET) and Gulf States Toyota (GST) may vary.
A 52 mpg excellent Camry Hybrid (2X better than the national fleet average) will be an excellent seller?
Posted by: HarveyD | 24 June 2017 at 09:06 AM