I discovered why the Tesla app did not want to route me through Flagstaff. Even though it is a shorter trip in terms of miles, the way I want to go is through the Apache National Forest. The two nearest superchargers between north side of the national forest and the south side is roughly 300 miles, and probably a lot of uphill and downhill driving. A M3LR might not make it all the way through. If I insist on going though Flagstaff, the other alternative route will be almost 100 miles farther going through Albuqueque NM.
As a new Tesla owner, for my own peace of mind, it's probably best for me to go through Phoenix. There are dozens and dozens of superchargers all along the way going this route.
I plan on subscribing to FSD for this trip. Any tips on using FSD? I have no experience with it. I have been using the basic autopilot with autosteer (not enhanced autopilot) and a couple of times it slammed on the brakes because of a dark spot on the road. Both times it was a rectangular piece of pavement where it was once dug up and refilled with new asphalt so the color is darker than the rest of the road. It was just typical road repair, nothing abnormal about it. But autopilot decided it was something else.
On the topic of navigating, choose a destination, then use the nav to add a waypoint. If it adds the waypoint in the wrong order/place, you can drag and drop it to the correct spot in the list. Basically, add a Flagstaff supercharger and make sure it is in the right sequence. Note that there are two SC's in Flagstaff, but the newer, faster one is not convenient to the interstate - you'll go 5 miles out of your way on the way there, and 5 more on the way back. Going to the Beulah St charger is a bit slower, but closer to the I-40/I-17 intersection. Be aware you can use the Marriott lounge at the slower SC. (Also note that you turn at the light to get to the SC - it's a bit tricky to find.0
On FSD - I've done that too. I find it extremely useful on the interstates, less useful the smaller and more crowded the roads get. I find it particularly useful to increase range as I can tolerate FSD driving at speed limits much more than if I'm driving. It allows the driver to be more of a passenger and look around. BUT - FSD can make a boring drive exciting when it does things like sudden phantom braking with a semi behind you. It's also very aggravating when the speed limit drops on the interstate. There are many places where a speed limit drops - curves, hills, odd traffic patterns - and nobody changes speeds. 80mph through it all - unless on FSD. You can have it set to go 80mph in a 70, but if the speed limit drops to 60, FSD will take you from 80 to 60 while everyone else wonders what you are doing. But mostly on rural interstates it is a wonder and a relief. That's FSD 11.4.9 for me, in a MYP. Still, you must always be ready to override in an instant. It's usually not hard to figure when you might have issues as they generally involve other vehicles, particularly big trucks. On things like speed limit changes, that's usually something you need to override, but not instantly. And sometimes FSD gets so weird in a stretch that you just turn it off, or drop back to TACC. Incidentally, you want Double Pull to engage FSD, or you will not have TACC to drop back to when FSD disengages.
Here's the rub on that - if FSD disengages, it has two options: drop back to TACC, or drop to total manual control. On the interstate, you don't generally want the car to drop back to manual as the speed drops immediately. On the other hand, in town you don't want FSD to disengage at a stop sign and throw you instantly into TACC which tries to take you back to speed immediately. The difference between these two choices is Double Pull or Single Pull engagement of FSD.
Next - charging. If going through the west, you often have a charger right where you need it, but no other choices. (Flagstaff is an exception). Therefore you don't really get the choice a lot of the time of doing 2x the stops for shorter charge times or one long stop to get through a long stretch. There can be a number of 125-150 mile stretches with no superchargers, and so you must stop as long as it takes at one SC to be able to make it to the next SC. On the other hand, if SC's are close enough, you can employ a dash-and-go strategy where you stop at 10% charge, then charge just long enough to make it to the next one with 10% charge - even if that is only 50 miles. The charging rate at 10% to 50% will be much, much faster than 30-70%.
When first hitting a long stretch between superchargers, go easy and see how your destination charge level tracks for the next SC. (Wind and temp can affect you a lot, which is why you want a 10% buffer to start with.) If you see your destination charge level actually improving, you know that you are driving slower for conditions than you need to. So I use a strategy where I start driving faster and faster to use up that 'excess charge', always with the idea of arriving at the next charger at about 10%.
Naturally you want to have the car running efficiently, no matter what speed you drive. By far the best thing you can do here is to have good tire pressure. The default is 42, but that's within a range of useable pressures. I generally set 45psi before a trip to improve mileage. (My father used to max tire pressures and tailgate semis across Nebraska...) Your car should also at least start clean.
Next, it really helps if you can eat and take your bathroom breaks while charging. Figure 20-30 minutes for charging, which is enough for eating at the Carl's Jr you are likely to see nearby a lot of interstate chargers. That worked well for me for two road trips to California from Phoenix, but my fiance said she can't continue to eat fast food at every stop. She's added a yoga mat for killing time at chargers.
It's when you are eating that you tend to get 'excess charge'. By that I mean that the charging happens so quickly you haven't finished eating before you have enough charge to continue. So you just let it charge up to 80% instead of the needed 50%. Now you might be able to skip the next charger or simply drive a lot faster the next leg. What you don't want to do is keep hitting chargers at 50% and going up to 80-90%. It's 2x or 3x slower charging to do it that way.
