Electric car conversion: Project ForkenSwift

[MetroMPG]

Originally Posted by SVOboy

It's so cool how you ev people help each other out so much!

Whatever happened with that batteries you just got?

Yeah, the EV community is pretty awesome.

The 4 additional floodies I got? They're still sitting in the flea, weighing it down. I'm using them to evaluate the aesthetics of cut springs

The NiCads were offered, but I didn't bring them home. Later this month I think I'll pick at least some of them up to play with & learn about. He also suggested I could use them in the Flea for 12v support when going alternatorless.

[MetroMPG]

Originally Posted by MetroMPG
3) A weird rubbery squeak/graunch type sound when the drivetrain is loaded up abruptly from a stop. It's either a motor/tranny mount complaining or the rubber spider in the motor/tranny coupler. Need to investigate.

It's a transmisison mount on the driver's side "frame rail". There seems to be a lot of play in the big rubber bushing, plus it makes the funny sound when the drivetrain is torqued up.

Question is: do those bushings fail and allow excessive play? Or am I just hearing a new noise with potentially the same amount of play that was there before?

The neat thing is with an electric car, I could test this by myself:

- put it in reverse, pull the hand brake hard, switch the key on

- get out, open the hood & activate the potbox arm to repeatedly load up the drivetrain while watching engine mounts & other stuff move around.

Try that with a (manual transmission) gasser!

[MetroMPG]

DaX suggests a fix for the weak mount:

The rubber in these mounts does tend to dry rot, crack, and fail, causing a loose mount. The cheapest and easiest solution is to go to AutoZone (do they even have those in CA?) or equivalent, and get a product that comes in a caulk tube called 3M Windo Weld:

Excellent tip. Thanks, Dax.

[TygerEye]

Thoroughly enjoyed reading you and watching your videos.

I like your approach: Jump in head first and engineer around obstacles as they pop up. I am a minor scholar of Thomas Edison and he used the same approach.

Unfortunately, this spirit of discovery has all but disappeared today. I am trained as a scientist and I believe people permit technology and communications to confirm every new idea is impossible or impracticable.
e.g. "Were it possible, one would already be doing it...!" The same sort of thinking which nearly shut down the US Patent Office in the 19th century.

We are fortunate to have some hardy pioneers as you and Ivan in your generation. Our society and our planet depend upon you!

[MetroMPG]

WOW. Nearly a month since the last ForkenSwift update.

I'm very happy to have this thread installed at EcoModder, and want to say thank you to everyone who gave their permission for me to quote their original comments & contributions here at the build thread's new, permanent home.

And that includes Tygereye's recent post. Heady words, those. Thanks for the compliment!

---

With that out of the way: a FS update. Two milestones...

1) I finally got the drive wheels to spin out! Woo! (But only because I've been driving it in the snow.)

2) And driving it I have been. Milestone #2: Last week the car passed its 500th electrically powered kilometer (300 miles). With the crap weather we had through most of Nov, "the electric umbrella" saw fairly regular use. Which equals something like one or 2 short trips (8-12 km) every other day or so.

Also, I murdered another battery (I think - I may have only gravely wounded it). The cold weather has taken its toll on range and performance - the voltage sags much lower under load.

More updates to come...

[MetroMPG]

Just got back from about a 10 km trip running errands in snowy weather. Some observations:

1) The crummy weather actually "opens up" more roads to the little EV that could, because traffic slows down in general. I drove straight through the Heart of Darkness this afternoon (the soul-less "big box" commercial/retail district) in moderate traffic, and no one was any wiser to the 12 hp EV in their midst.

2) When you've got so little energy on board, and it's further sapped by the temperature and road conditions, you become really aware of the need to use "trip chaining".

3) Reverse 180 spin-outs (on purpose!) are just as much fun in an EV as an ICE car.

[SVOboy]

1) That's also something I like about a good light rain. Less people driving during non-commute times means the drive is a bit more peaceful. Isn't that a good book, too?

2) Did you notice a significant decrease in top speed?

3) Nutter!

[MetroMPG]

OK, did my first batch of MPGe calculations, and stuck it in the car's gas log.

Man - what an oinker! Now, this is calculated at the plug, not at the battery pack, but still - that's the way the EPA does it.

50 km / 31 miles total, 6 charge cycles, using 16.7 kWh total according to ye olde kill-a-watt.

Conversions: 3412 BTU/kWh; 114,500 BTU/gal (US).

One thing I noticed is there's a correlation between distance driven and MPGe. The shorter the distance driven before recharging, the higher the energy consumption.

It's somewhat of a weird concept, but it makes sense. Charging is most efficient when the batteries are empty - they'll gulp down the amps as fast as you can feed 'em (within reason), and SOC will rise rapidly in response. But as the batteries approach "full", the charging efficiency seems to drop. The batteries bubble and burp and heat up (relatively). It takes more and more to push them that last 10-20% to "full".

Also, the charger has a 3 hour timer for its "finish cycle". So if I unplugged the car fresh from the charger, drove it down the driveway and back, and plugged it in immediately, it would take 3+ hours to give me the "fully charged" light again.

Also also, if I leave the charger plugged in after the "fully charged" light comes on, it keeps trickling the pack, lowering the MPGe calc of the previous drive cycle.

Also also also, the pack loses charge just sitting idle. If I drive it over the course of a couple or 3 days before recharging, I'll get lower MPGe than if I drive the exact same route fresh off the charger.

So complicated!

Anyway - it's good to have a baseline. Time to start figuring out how to hyperwatt this puppy.

[Lazarus]

Originally Posted by MetroMPG

Anyway - it's good to have a baseline. Time to start figuring out how to hyperwatt this puppy.

Hyperwatt fabulus I love that term. Man that is complicated.

[Thalass]

Your kWh figure was for the total 50km? That works out to just over two cents per kilometre, with the numbers I could find online for my area. (Couldn't find a power bill in the house. heh)


That's about the same as other conversions I've found the figures for. Averages out to about 2-3c per kilometre. Compared to my 1999 subaru outback, that costs me 12c per kilometre!


So I figure that 25000km (which I'm told is around the usual yearly distance for most people) would cost $625 (australian) for an EV, and $3,223 for the standard petrol car!


I just need a garage and a donor car so I can start my own conversion. :P