Why Your Quad-Motor Rivian Officially Has 872 HP

The documents that join your brand-new car on the delivery day can sometimes prove a bit tricky. In Rivian’s case, one may raise some eyebrows – the Manufacturer's Statement of Origin (MSO). This somewhat standardized piece of paper may create some confusion about the total power output of the vehicle. But do the R1T and R1S have 872 hp (884 ps), as it says on the document? Let’s dive in and find out.
Rivian R1T and an MSO 14 photos
Photo: Top Gear on YouTube / Anthony Schneiderhorn on Facebook / autoevolution edit
Rivian R1T MSO/MCORivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1T in Off-Road Drift Drive ModeRivian R1SRivian R1SRivian R1SRivian R1SRivian R1S
Firstly, we begin with a friendly warning! If you want to find out right now why the MSO of a Rivian states that the quad-motor versions of the all-electric pickup trucks and SUVs made in Normal, Illinois are capable of 872 hp... Well, you have to scroll near the end of this piece. We are approaching this topic meticulously, and it is going to be a while before we can get to the answer.

Secondly, if you bought or leased a Rivian and are among the lucky ones who took delivery of one, chances are the MSO attracted your attention. That's because of one little detail – the larger total power output.

Thirdly, we must clarify one important aspect - the Manufacturer's Statement of Origin (MSO) and the Manufacturer's Certificate of Origin (MCO) is the same. Whatever version of it you may get, the thing to remember is that it is a vital document in most parts of the U.S. It nearly looks like a Certificate of Title in all 50 states. That's because there’s no federal standard enforced. Some jurisdictions have different rules, formats, and names in place.

Rivian R1S
Photo: Rivian
To keep things simple along the way, we’ll refer to this document as the MSO.

Not everyone's on the same page

This important piece of paper is given only to the owner of a brand-new automobile by the selling dealer. It includes a couple of essential details like the unit's year of production, the make, the model, the vehicle identification number, and the gross vehicle weight rating (GVWR). It also stipulates the vehicle's shipping weight, the number of cylinders (zero for BEVs), the body type, and the date when the document was generated.

The MSO’s initial role is to certify that a vehicle was made by an NHTSA-vetted company and that it was sent to an incorporated third-party known commonly as the dealership. Since Rivian does not have middlemen, the name you’ll find on this document is going to be… Well, Rivian! In some instances, an employee’s name might be included instead of the automaker’s, but that does not change anything.

Rivian R1T in Off\-Road Drift Drive Mode
Photo: Top Gear on YouTube
Afterward, the document is requested by entities like the finance office to certify any extras (e.g., the extended warranty). Its last role is to show the people working at the Department of Motor Vehicles (DMV) that the car was made and exists because that’s how the first title and registration are obtained.

Time for some math!

If you live in a state like California, where dealers and manufacturers that adopted the direct sales model are forced to register the car for the buyer, chances are you’ll never set eyes on the MSO.

But if you live in a state where the MSO is handed to you for registering a new vehicle for the very first and getting the first-ever plates for that particular model, you might take a look at the MSO before giving it to the DMV.

That’s exactly how someone from Missouri found out that their brand-new all-electric Rivian R1T with the quad-motor layout is putting out 872 hp and not 835 hp (847 ps) like we’ve all been told.
It’s important to add here that Rivian officially says its quad-motor all-wheel-drive vehicles “have more than 800 hp (811 ps) and more than 900 ft-lb (1,220 Nm) of torque.” Since bigger numbers are always better for bragging rights, it’s peculiar that the Irvine-based automaker chose to refrain from saying something along the line of “nearly 900 hp.” But there’s a good reason for that!

Yes, it does say 835 hp on the R1T and R1S online spec pages, but the above quote was taken right from Rivian’s Frequently Asked Questions (FAQ) page.

Rivian R1T in Off\-Road Drift Drive Mode
Photo: Top Gear on YouTube
Fourthly, nobody has managed to reliably do a dyno pull with a Rivian vehicle – for now, at least. Somebody tried almost a year ago, but the torque management system (aka the stability control) kicked in and stopped the vehicle from reaching its full potential for an accurate reading. The vehicle’s sensors mistakenly identified walls as traffic participants and told the computer a crash could be imminent. That’s how power was cut, which is like what Teslas were doing before Dyno Mode was introduced.

So, why does the MSO say 872 hp?

The official power output for a quad-motor Rivian vehicle is expressed by the Environmental Protection Agency (EPA) in kW. The Bosch motors have a maximum rating of 324 kW for the front axle and 326 kW for the rear axle. This tells us that an R1T or R1S with one motor for each wheel is theoretically capable of putting out 650 kW. When this figure is converted to horsepower, the result is 871.6 hp (883.6 ps). The EPA rounded it up and got 872 hp.

Naturally, you may now wonder why the EV maker says that its quad-motor units come with “more than 800 hp” or 835 hp and why doesn’t it use the figures coming from the government. That’s because Rivian would lie to you. The total gross output is never equal to the net.

The four motors are theoretically capable of 872 hp when pushed to the limit, but they require cooling, and the battery must be able to sustainably work with the driver’s request for increased acceleration. Plus, physics dictates that mechanical losses will occur when friction and air turbulence are involved.

Finally, in the name of safety and reliability, all you get are 835 hp, even though the MSO may add 37 hp more.

Video thumbnail
If you liked the article, please follow us:  Google News icon Google News Youtube Instagram Twitter
About the author: Florin Amariei
Florin Amariei profile photo

Car shows on TV and his father's Fiat Tempra may have been Florin's early influences, but nowadays he favors different things, like the power of an F-150 Raptor. He'll never be able to ignore the shape of a Ferrari though, especially a yellow one.
Full profile


Would you like AUTOEVOLUTION to send you notifications?

You will only receive our top stories