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Rivian performance claim vs reality, for the 0-100mph.

Rivian_Hugh_III

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Just did a First Mile test drive yesterday. To me it feels like there's some strange throttle mapping going on. For instance, to me 0-60 for the first 30 felt sluggish (in relative terms) and then you can feel the truck pull exponentially harder from 30-60. It almost feels like a turbo kicking in on a combustion engine. As a Model 3 owner, it felt strange to me because the 3 feels linear in its acceleration. Might be something I would get used to, but my initial take was that it felt a little odd.

A friend and fellow Rivian orderer asked me what my thoughts were after test driving. I told him that I know it sounds weird to say, but it felt like an electric truck. The point being, my frame of reference is a Model 3, so I assumed that's largely how all EVs would feel like. The R1T felt solid, substantial and heavy, sort of like a truck (go figure). The Model 3 by comparison feels light and snappy like a fighter jet. The R1T feels more like an absurdly fast tank.
The sluggish 0-30 could be because this is a *truck* that may well have gear or cartage in the bed. You don’t want that stuff slamming into the lift gate.

In the future we may see a launch option that breaks 3 seconds. Perhaps a $10,000 plaid upgrade. It could make sense to keep that available and up the sleeve.
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ajdelange

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As I often do I have used engineering terminology here and expected everyone to understand it which may have resulted in some confusion. Off the line the goal is to apply as much thrust to the vehicle as possible to accelerate it as much as possible. This is done by increasing the torque and measuring the slip. As long as the slip is below some threshold value slip and thrust increase proportionally and the proportionality is linear. Increasing torque 5% increases thrust 5%. At the break point this is no longer true and additional torque only causes the wheel to "slip" without delivering more thrust. Thus the controller applies as much torque as it can without "breaking". If conditions are good (dry smooth - but not too smooth) surface the applied torque will remain constant at the drive's maximum deliverable torque, thrust will be constant and so, therefore, will be the acceleration. The speed will increase linearly. The power taken from the motor under constant acceleration is proportional to the speed and so it is also increasing linearly. Eventually the power required limits the motor's performance and we transition from its "torque limited" region to its "power limited" region. If you are being judged on 0 - 60 time the obvious strategy is to have the power limited region start at 60 mph.
 
 








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