The $106,000 Rivian R1S electric three-row SUV was dogged with shortcomings. So I was eager to see what the automaker would do for its next generation of big hype, big price tag vehicles.
The upgrades for what Rivian is terming as the second generation of its R1S SUV and R1T pickup truck directly address the SUV’s unexpectedly harsh ride while also cutting the price. In doing so, Rivian has confirmed the accuracy of my criticisms at that time, which is a bit of a relief. The negative review of the R1S came as a surprise to no one more than me, after I loved the company’s R1T pickup truck at its launch in 2021.
But Rivian launched the SUV using the same suspension settings as the pickup, despite its shorter wheelbase and resultantly different weight balance. It also dramatically jacked up the vehicles’ prices in response to overwhelming demand for the cool-looking EVs at a time when Rivian’s factory was struggling to increase production.
Enduro Motors
What’s changed? The Rivian-designed and manufactured Enduro motors have now replaced the Bosch-sourced motors across the entire R1 family of models. These motors not only cost less than the outsourced motors, but are more powerful. Oil cooling also means that they have more robust thermal management, so the R1s are less likely to reduce power due to excessive heat.
The vehicles are now available configured with either a pair of motors with one driving the front wheels and the other driving the rears in the Dual-Motor models or with four motors, with one driving each wheel in the Quad-Motor. As before, the Dual-Motor is available with standard power or with the software-upgradable Performance option for more oomph. The second generation adds a new option, the Tri-Motor, which mounts a single motor driving the front wheels and a pair of motors driving the rears.
Rivian learned from the original vehicles that having identical motors front and rear was not optimal, because the front wheels couldn’t use all of the available torque and the rears needed more for catapult-launch acceleration. So Rivian juggled the sizes of the front and rear Enduro motors, mounting motors that are 85 mm long in the front and 110 mm in the rear.
These motors produce absurd power that yields ridiculous performance numbers. They are:
- Dual-Motor, 533 horsepower and 610 lb.-ft. torque
- Performance Dual-Motor, 665 hp and 823 lb.-ft.
- Tri-Motor, 850 hp and 1,103 lb.-ft.
- Quad-Motor, 1,025 hp and 1,198 lb.-ft.
The 0-60 mph acceleration times for the configurations are 4.5 seconds, 3.4 seconds, 2.9 seconds, and “less than 2.5 seconds” respectively.
The Rivian hot-shoe driver has recorded a 2.43-second 0-60 run and ripped through the quarter-mile in 10.5 seconds. As the Farmer Hoggett character told his sheep-herding pig in the classic movie Babe in understated style, “That’ll do.”
Zonal Architecture
The company has also simplified and improved the electronic guts of the R1, replacing the original wiring loom with a cutting-edge “zonal” architecture that eliminates 1.6 miles and 44 pounds of copper wiring. The 17 electronic control units have been consolidated to just seven ECUs for the second generation. Along the way, 80 connectors have also been eliminated, simplifying assembly and reducing the potential for future problems.
The benefits of the new arrangement are obvious, and the time since the first vehicles debuted is short, I’m left wondering why Rivian didn’t do it this way from the beginning. “I’m glad you asked,” is effectively the answer from the company.
When the engineering teams were in crunch time, toiling to deliver their various subsystems for the original launch, they had to be able to deliver stand-alone systems, explains Rivian’s Director of Electrical Systems, Kyle Lobo.
[Related: Used EVs are getting cheaper. Should you buy one?]
With the first-gen vehicles on the road, teams have had time to coordinate, so they can develop systems that share ECUs for better efficiency and reliability. Now, only the infotainment, autonomy, vehicle access, and battery management systems have their own ECUs, Lobo says. All of the other remaining functions are handled by the three remaining ECUs.
“Now you’re asking all these teams to live in the same house, share the same processor, allocate the same RAM, so that just takes a lot more resources and learnings from doing it the first time,” Lobo says.
Batteries
Samsung has increased the energy density of the 21700 cells employed in Rivian’s Standard Pack and Max Pack batteries from 50 amp-hours per cell to 53 amp-hours. This, along with changes to the wheels and tires that reduce rolling resistance and aerodynamic drag, boost the driving range by ten miles. So now the Max Pack reaches 420 miles for the R1S and 410 miles for the R1T. It is a tribute to the fact that the company is run by adults and not Elon Musk that there is no special “420” edition commemorating this mileage number.
There is a new lithium-iron phosphate Standard Pack, that provides a driving range of as much as 270 miles. These batteries not only cost less to make and have the bonus of avoiding problematic materials like cobalt, but their individual cells are also larger, so assembly is simplified, reports Rivian’s Director of New Technologies, Max Koff.
“Because you’re switching to a larger cell, you have less connections,” Koff said. “These are all placed in series, so you’re essentially taking that simplification and efficiency from a cost perspective, and passing it on to the customer.” As with all EVs, the range estimates depend on the exact tire/wheel package selected, as well as the drive motor configuration.
These cells, whether the cylindrical Samsung cells or the pouch-style lithium-iron cells that Rivian first used in the Electric Delivery Vans the company builds for Amazon, are installed in a new housing. The original housing was made from extruded aluminum, which was costly and suffered from manufacturing variances. Second-generation Rivian R1 vehicles have a die-cast aluminum housing that weighs an impressive 150 lbs. less than the previous design while providing 0.1 mm dimensional accuracy.
Autonomy
The new brains in the R1’s driver assistance systems are supported by improved cameras and radars that provide the computer with information about the vehicle’s surroundings.
The updated compute platform is 10 times more powerful than the first-generation system, at 250 trillion operations per second, courtesy of the dual Nvidia Drive Orin processors. “For most customers, their R1 Gen 2 will be the most powerful computer that they own,” says James Philbin, director of autonomy.
Data pours into these processors from 11 high-resolution cameras and five radars that provide 360-degree vision for the R1. The cameras combine to supply eight times as many megapixels of imagery as the previous camera suite, with the ability to see three times farther ahead thanks to installation of a new narrow-field-of-view front camera.
The cameras are backed by the radar units, which have different capabilities, such as the ability to see in bad weather and dim light, explains Philbin. Camera images have no depth and collect no information about objects’ velocity, he pointed out. “We are leveraging the strengths and mitigating the weaknesses of our sensor data.”
On, and Off, the Road
The new specifications are fabulous, but it is important to know how the changes deliver results for the driver. The ride and the handling of the R1T pickup were already superb, so Rivian has left that vehicle’s suspension unchanged.
The R1S finally gains the unique calibration it should have had from the beginning, with stiffer springs, softer damping, and better roll control from the advanced cross-linked hydraulic damping system whose only apparent limitations are in the programming. The good news is that the changes work, delivering a much-improved on-road driving experience during a day of driving on rural highways outside Seattle and on the city’s streets.
The R1S can still be harsh over legitimately serious impacts like potholes, but now the calibration is much closer to ideal. I considered the previous vehicle’s ride to be disqualifying for the R1S to be a candidate for purchase. That is no longer the case. Now, the ride is fine. There are still many vehicles that deliver a more comfortable ride, or that deliver a better balance of ride and handling, but Rivian’s SUV is at least now in the game.
The new motors and their control systems deliver obvious benefits when off-roading. Navigating a very muddy course at the Dirtfish rally driving school, the Performance Dual-Motor R1S demonstrated improved ability to put its electric power to the ground compared to the first-generation Dual-Motor vehicle I drove at Rivian’s Illinois factory course last year.
A year ago, putting power to the four wheels from two motors through differentials delivered an off-road experience pretty similar to that of a combustion-powered vehicle. I could easily discern intervention from the vehicle’s traction control system as it applied brakes to control wheelspin and shift power to a tire with grip.
This was a contrast with the Quad-Motor vehicle, which ascended the same obstacles as if by magic, as the computer control of each motor was precise enough to prevent the need for any traction control intervention. Driving the second-generation Performance Dual-Motor over obstacles that were specifically designed to stymie progress, the new vehicle picked its way forward nearly as effortlessly as a Quad-Motor.
This is because the second-generation vehicle is measuring electric motor speed at the inverter rather than at the motor, so the computer knows what is happening in more granular detail. The difference shows.
The Price Is Right
The best news for prospective buyers is that all of this newfound goodness costs less than the previous-generation vehicles. The Dual-Motor Standard Pack R1T starts at $69,900, getting entry pricing back down near where Rivian started in 2021. The R1S costs $6,000 more and the step up to the Large Pack battery adds another $7,000, with the same price increment again for the Max Pack.
The Tri-Motor R1T is $99,900, and the SUV is still an additional $6,000. The company hasn’t set pricing for the Quad-Motor.
It is good for carmakers to have halo models to create favorable impressions of their vehicles, but it is hard to imagine who could possibly use the Quad-Motor’s power. Though it is surely the most capable model in serious off-road conditions, so there are a few people who could benefit.
The rest of us will surely be choosing between the Dual Motor or the upgraded Performance Dual motor, with some mental wrestling over whether we can live with the cheaper 270-mile battery pack or if we need the 420-mile battery. The best part is that, for non-pickup buyers, the R1S is fixed so it rides satisfactorily, putting it back onto the shopping list.
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