Electric car conversion: Project ForkenSwift

[Silveredwings]

Originally Posted by MetroMPG

Well, the 400A unit has a user-settable acceleration ramp (via a pot), and a couple of other adjustments. Haven't played with them yet.

I always found the 225A acceleration ramp to be sluggish - it definitely wouldn't give you 225A immediately from a standstill (though you could get it under way). And it would bog down in thick snow at low speeds (ie come to a stop, with no amps showing on the meter).

I see. 225A to your motor and car weight it is sluggish. Maybe on a bike with a smaller motor, it would be blistering or even hard to control.

Still, it seems like putting a slower 'acceleration ramp' on the 225A is a little like taking a guitar amp and graduating the volume control so "it goes to 11."

[MPaulHolmes]

I'm sure you know this already, but check out ebay! 100 72v 400 amp curtis controllers!!! Cheap starting bids!

[MetroMPG]

Great find. Thanks for posting that. I need a sixth controller.

[bennelson]

Yep, 5 more ForkenSwifts and you can carry them around in a six-pack ring!



I may need to keep an eye on these for my Metro build.

[PeteM]

Hi,

Nice work on the Forkenswift, I've spent a few hours over the last few days getting educated on your build.

I am currently looking into building my own EV and I am stuck on the process of getting the car certified for the road. Can you point me to any documentation or Ontario Gov web sites with details on what needs to be done?

I gather from your build that the process included getting the donor car certified first and then converting, so I would probably do the same, it's the post convert process that I am interested in. Can any Motor Vehicle Inspection station do the work, or did you need to find a "special" place?

Thanks,


--Pete

[MetroMPG]

Hi Pete-

There aren't any documented rules you need to follow to have an EV conversion certified in Ontario. We thought having it certified before doing the conversion would simply save some hassle having to do a lot of explaining, so that's what we did. But it turned out the insurance company required an additional inspection anyway (since the original inspection had expired after 30 days or whatever it is, not because it was an EV).

That said, I'd take the vehicle to a mechanic you have a relationship with already, since they have a lot of lattitude to interpret the regulations and you want someone who will help you to make sure the car is safe, not simply throw up road blocks. I used my regular mechanic that I've been going to for several years.

You might want to ask on the Durham EV Association Google group for specific recommendations in the Toronto area. Their website: http://www.durhamelectricvehicles.com/

Their discussion group: http://groups.google.com/group/Durha...iation?lnk=srg

[RarestAce]

i just finished reading your whole conversation and i must say what an amazing job you guys have done. I really cant wait to see what your car can do with the 400 amp controller

[MetroMPG]

Hi RarestAce - thanks for the compliment. The 400A controller is great. It's nice to have the extra power when needed, which is rare, but better than willing the car forward when more accel is needed. FYI, accel to 50 km/h is 21 seconds vs. about 36 seconds with the 225A unit.

---

Update!

Ivan and I will be pulling the car apart probably next week to clean it up - paint the motor compartment, components, and generally tidy up the installation. But before that we wanted to get a better picture of the health of this set of batteries.

So... yesterday we installed the LED pack monitor I talked about back here.



It's awesomeness can't be underestimated. Up to now, we've only been monitoring a single battery in the pack - the one we thought was the weakest. Rule of thumb: avoid drawing the weakest batt below 5.25v under load.

Well, oops. Within 15 feet of driving, the dancing equalizer-like LEDs showed us several things, not the least of which was we were NOT monitoring the weakest battery all that time. We had a true dud in the pack that fell on its face under the lightest load.

I'm going to post pics, and maybe make a short YouTube vid about this handy device. It's very cool to watch, and immensely useful. Every EV should have one (esp. if you've got an older, less balanced pack).

[RarestAce]

thats great when its all done it sounds like it's be one sweet little car to drive around. hopefully you'll be able to get yourself a nice set of batts one day but its just a great project thumbs up man

[MetroMPG]

If we keep the car long enough to completely wear out the 2 sets of old batteries we have, I'm sure we'll feel like a new pack will be worth the investment.

Besides: now we're properly equipped so that the investment would be protected: the combination of the proper 3 stage smart charger and now a proper means of monitoring the pack means it wouldn't be abused by our (old) dumb charger or damaged out of ignorance from over discharging the weakest battery(ies) while driving.

I'm definitely going to make up a short YouTube vid showing the LED pack monitor. It's too cool.