REX speeds for long highway drives

[bencpeters]

I'm considering buying a REX that is located about 1000 mi away from where I live. If I end up getting it, I'll probably just ship it, but I was wondering a bit about the feasibility of driving it back as a road trip after reading some of the long distance accounts here. I'm a software engineer, and would be very comfortable/plan on hacking the increased gas tank volume & ability to put the car into charge hold mode at a higher SOC, both of which seem fairly essential to a long drive.

My question is, for those who have experimented with this - if you activate hold charge mode at, say, 50% SOC, can you reasonably drive ~70-75 mph indefinitely with the REX running (barring long mountain passes and with the caveat that you'd need to fill up every 100 miles or so)? The drive home would be mostly flat mid western highway, but going through Wyoming on I80 at the end.

Or should I just ship instead?

Thanks!

 

[jadnashuanh]

Personally, I'd ship the car. 70mph on the flat, the REx can keep up, probably just barely. But, considering the spacing of service stations and the indication from others that the REx gets about the equivalent of 34-38mpg, you'll probably need to be stopping MUCH more often than once every 100 miles. Unless you play tricks (not shutting it off, exiting via the passenger's side), when the SOC drops, the REx may not be able to bring it back up again. Eventually, you'd need or at least want to plug it in. If you're really lucky, you might find a place along the way, but would probably have to get off of the interstate to access one. In a few years, that may change, but for now, that seems to be the case, at least in the middle of the country. While it would be an adventure, especially if you're doing this now in the cold where you'll take a range hit, I would not do it. On the REx, if you want cabin heat, it all comes from the battery. On the BEV, at least when it isn't really cold, it uses a heat pump which can be 2-3x more efficient at getting heat into the car. While driving it with just the seat heaters on, doing that for 1000-miles would, I think, get old. With the shorter days, you'd have the lights on most of the time, and maybe even the high beams in the middle of nowhere, and every load just adds up.

FWIW, you really shouldn't be refueling any car with the motor running. Yes, I know people do it, but it isn't the best practice, and if you do shut it off, the current SOC is the max the REx will try to attain unless it is in the critical single digit SOC area. Now, depending on the SOC, the REx usually will stop when you are not moving, but that's not guaranteed.

 

[RExingIT]

I'd also recommend shipping it. I've not doubt in your capability of coding the car, but you're basing the whole trip on that working first time as well as being able to find a gas station every hour. This sounds like allot more work than simply just getting the vehicle shipped. Over a 1000 mile trip, you will need to have reliable spaced gas stations about 60 miles apart as I'm assuming you will need to be using the heat and dehumidifier due to the current weather. While this is not imposible, it does mean stopping for fuel around 15 times and not having any gaps in your service.

Just my 2 cents.

 

[redbarn]

We do monthly 500 mile each way drives with our Rex but it is coded to Euro spec.
With 3 CCS superchargers en route now, the journey is quite doable.
Fuel stops are circa 80 miles and we carry an emergency 2 gall gas can in the frunk.

But to do a 1000 mile trip without reliably knowing that the Rex is in Euro spec would be actually dangerous. Too many things can go wrong, even if there were some reliable charging stops en route. The journey could wreck your whole I3 experience.

Ship it.

 

[janner]

You should be broadly breakeven at 20x your journey average miles/kWHrs.

Code the car to turn on at 75% battery SOC.

Bring up trip details on split screen - one of the lines will be the trip miles/kWHr.

Drive first 25% of battery SOC and then turn on ReX.

You can drive at 20x the trip miles/kWHr - 3.2 = 64mph, 3.5miles/kWHr = 70mph, 4m/kWHrs woyld be 80. This accounts for load, speed, acceleration, heating etc. This is because the ReX produces 20kW at 3600rpm above 56mph.

My experience is that it s drives very well at 65mph sustained. Keep an eye on the SOC% - you'll see it drop going uphill and increase going downhill.

When you stop for gas you will lose charge due to the compressor and fan for the battery cooling and for the REX radiator cooling fan and pump.

If you think of 70 miles between gas stops that's 15 or so stops and about 20 hours driving. If you had two overnight stops and could set off with a full charge in the morning, then why not. Otherwise ship it as the others suggest.

 

[imolazhp]

First and foremost, it is NOT A HACK. You are not changing any lines of code, all you are doing is changing settings, BMW owners have been doing this for YEARS. The i3 is not the first car with the ability to have things coded, nor will it be the last.

That said, this is exactly what I did, but my travel distance to home was only about 420 miles. Saved me $600 in shipping, I took a bus (don't laugh, yes, I took a bus to buy the most expensive car I've ever purchased) and with food spent less than $80 getting there and driving the car back. Not to mention the $55,850 at the dealership, well, that was the MSRP, not the price paid, but still. Now that I have the car "home" I am not so keen to take it back out of town, I have not yet had any flats (knock on wood) but the car does not have a spare. I have added a plug kit to the frunk and the car does come with a bottle of goo and an air compressor, but still.

Do it, you won't regret it, have fun. Just be sure to have your laptop charged and all the programs you need uploaded and ready to go. I had never coded a car previous to my i3. Now that I have the experience I am kicking myself for never doing the coding things I wanted to do to my e46 for so many years. I would suggest keeping it simple, just get in there to code the REx HSOC and the fuel tank to 8L and get out and get back on the road. Play with the other code'able features after you make it home safely.