PDM/DM/QM Need input to confirm order

[GRC]

All, thank you in advance for your input.

I had made up my mind based on the forum and all the info gathered that I will pursue a PDM version of the r1s. This decision was primarily based on getting the maximum mileage since a dual motor option was not available for me at that time. Now I noticed that I have shop access and have access to all three variants of the R1S.

I am pasting below the screenshots I see when I look at the mileage of the three variants with the 21" tire option which also I decided based on maximizing mileage since I would have preferred the 22 inch more.

DM - 566kms w/21"
PDM - 548kms w/ 22" (can't see a config with 21" to get EPA) should be something lower than 566 and higher than 548kms since screenshot below for PDM is w/ 22"
QM- 516kms w/21" and 487kms w/22"

A question and an observation:

1) is it true that if I go with the QM and use conserve mode I can get the same mileage as the DM? (So would I get the 566 KMS on the qm model using conserve?)

2) there appears to be a small discrepancy in the PDM versus DM numbers. My understanding is that PDM gives you higher performance and therefore a lower mileage. In a QM model I loose 29kms going with 22 inch tires over 21 inch. If I assume that the loss of mileage is the same then a PDM model with 21 inch should be giving me 577kms (548+29) which would put this above the DM model. But this can't be true because DM should give better mileage than PDM correct?

#1 is the key deciding factor for me. #2 was just to get people thinking and doing some math and maybe there is a good explanation for this

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[R1Tom]

If range is most important....go with the DM. With the DM you get the range of conserve or better without the negatives of running around in conserve in a QM at low speeds.

For me...other criteria are up top, so QM is my choice, but if hypermiling is the goal....DM and let it engage and disengage that rear motor for max range without running around at lower speeds in front wheel drive.

 

[ksurfier]

Without making this overly complicated, yes - the QM with 21" should be able to get ~550 km range in Conserve. Range is very much temperature dependent, with a big difference between 4c (40F) and 27c (80F), in this case almost 30% reduction in range for the colder weather. Speed is major factor as well, for example, 37.3 km/hr (60 MPH) is 16% more efficient than 43.5 km/hr (70 MPH).

So all of this being said, range at 80F driving 60 MPH is nearly 555 km (345 miles), but range at 40F driving 70 MPH is only 370 km (230 miles), as you can see a lot of variation...

 

[R.I.P.]

All, thank you in advance for your input.

I had made up my mind based on the forum and all the info gathered that I will pursue a PDM version of the r1s. This decision was primarily based on getting the maximum mileage since a dual motor option was not available for me at that time. Now I noticed that I have shop access and have access to all three variants of the R1S.

I am pasting below the screenshots I see when I look at the mileage of the three variants with the 21" tire option which also I decided based on maximizing mileage since I would have preferred the 22 inch more.

DM - 566kms w/21"
PDM - 548kms w/ 22" (can't see a config with 21" to get EPA) should be something lower than 566 and higher than 548kms since screenshot below for PDM is w/ 22"
QM- 516kms w/21" and 487kms w/22"

A question and an observation:

1) is it true that if I go with the QM and use conserve mode I can get the same mileage as the DM? (So would I get the 566 KMS on the qm model using conserve?)

2) there appears to be a small discrepancy in the PDM versus DM numbers. My understanding is that PDM gives you higher performance and therefore a lower mileage. In a QM model I loose 29kms going with 22 inch tires over 21 inch. If I assume that the loss of mileage is the same then a PDM model with 21 inch should be giving me 577kms (548+29) which would put this above the DM model. But this can't be true because DM should give better mileage than PDM correct?

#1 is the key deciding factor for me. #2 was just to get people thinking and doing some math and maybe there is a good explanation for this

For number one, no, Even in conserve, the QM is not quite as efficient as the DM.

Even in conserve mode, the QM is running two motors, and two inverters, aggregating those losses.

The DM is running one higher efficiency inverter, and one arguably (slightly) more efficient motor. This cuts your losses, which are most easily seen on long runs.

 

[MidnightRivian]

QUAD MOTOR FTW. Go with 21" tires for range and down the road upgrade to 20" All Terrain when you go off-roading.

 

[jjswan33]

I don't think you will see any efficiency difference between the DM and PDM unless you use sport mode a lot.

Personally I would get the DM and save the money, I have no need to go 0-60 in less than 4.5s or whatever. Coming from a current QM owner.

 

[Eric9610]

Dont forget the QM and large pack has the best warranty offered by Rivian. Its a significant difference if you are keeping the car long term.

Also on my QM not in conserve mode I have got 345miles now on 2 trips. Rivian is very conservative on number.

 

[HaveBlue]

The pdm is a dm and gets the same range and performance in all purpose mode. This is the mode you will be driving daily. I think how you drive will have a bigger effect than whether you pick the 21s or 22s.

 

[R.I.P.]

The pdm is a dm and gets the same range and performance in all purpose mode. This is the mode you will be driving daily. I think how you drive will have a bigger effect than whether you pick the 21s or 22s.

You will get four to five percent better on 21s than you will on 22s. I found 21s to be my friend when hypermiling across the Mexican deserts.

But yeah, I'm betting most people are never going to miss that 4% lol.

 

[GRC]

thank you all - after considering all things, I decided on QM - will drive on conserve most of the time but feel that the longer warranty will be helpful for me.

 

[R1Tom]

thank you all - after considering all things, I decided on QM - will drive on conserve most of the time but feel that the longer warranty will be helpful for me.

My technique is use All Purpose day to day when ultimate range isn't needed. Charge to 70%. Sport mode if I feel like driving fun.

Then when I need ultimate range(which is 1-2 days a week)...I charge to 100%....use All Purpose to get to the interstate....once up to speed on interstate...I switch to Conserve. Then...when I exit interstate and speed is down under about 25....I switch back to All Purpose. I figure that is easier on the disconnects. But not sure that is necessary. Their have only been a few reports it seems of those failing. The disconnects seem to be a pretty robust design.

With that approach, I am at 37K on 20" tires and still have probably 5k left on them...maybe more.

I do like that I still have 23k of warranty left and not 13k if I had a DM. But I wouldn't hesitate to get a DM if I had a need for every last mile of range it has to offer.

 

[BCondrey]

For number one, no, Even in conserve, the QM is not quite as efficient as the DM.

Even in conserve mode, the QM is running two motors, and two inverters, aggregating those losses.

The DM is running one higher efficiency inverter, and one arguably (slightly) more efficient motor. This cuts your losses, which are most easily seen on long runs.

Actually, it is better than that. DM uses the rear motor and the front motor when you start moving. It de-couples the rear motor when the torque decreases, you reach about 20 mph. You keep accelerating and the rear motor stays engaged. The rear motor is geared differently for more torque for this reason. So you use both motors to get started, and then it settles in on the front motor. It is very smooth and you don't notice the decoupling. If you punch it to pass someone or accelerate, the rear motors kick in. The QM in conserve mode doesn't do any of that, it is just the front two motors. The PDM is the same as the DM, except that there is more horsepower when all four motors are engaged. I've owned QM and DM and I prefer the DM. The efficiency is very good, I'm getting 2.5 to 2.6 for 30 mile trips when I precondition.

 

[Eric9610]

thank you all - after considering all things, I decided on QM - will drive on conserve most of the time but feel that the longer warranty will be helpful for me.

Good choice! In reality you had no bad choices.

Related to conserve mode, I would only put it in that mode when you know you are taking long trips and keep in in all purpose for daily driving. It has been reported on this forum that conserve mode chews through the front tires very fast. It makes sense as you are using 2 wheels to move 8k lbs and turn.,

 

[GRC]

Thank you for that info. Noted and will keep in all purpose at all times unless I need the extra mileage

 

[Eric9610]

coming from a Tesla and non realistic range, the Rivian is so accurate. Evey time i have used the navigation I have arrived with more leftover range than estimated by 3-10 miles.

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