EV build...feeler thread

[ModelE]

so i have before me a nice opportunity...

a basically free 1995 ford thunderbird, that i'm thinking of converting to an EV
now the only things i'm worried, is that its a 4 speed auto, and weighs a tad over 3500 lbs curb weight in its current form. now, do those disqualify it as a relatively budget sorta EV conversion, all other factors notwithstanding?

[Christ]

That 3500# weight is VERY misleading. There is lots of luxury componentry in the T-bird and Cougar of those years, and they can be put on a diet of almost 1000 lbs easily.

IIRC, I had my 1992 Cougar down to like 3000# just by removing things.

[ModelE]

thats very helpful actually, i know that they have lots of extra stuff...but yeah that sounds really good! 1000lbs would be good. and what about getting rid of all the power windows and power locks, etc etc. or is that not really necessary....

[Christ]

If you want a power window, keep the driver's side. (I had straps to lift/lower my windows.)

Power locks are worthless, but if you want something cool, remove the locks, leave the solenoids, and connect them to the latch. When you push the button, the door opens.

You'll need to remove the speedlock system though (when you start moving, or put it in gear, the doors lock) as this will cause your doors to open when you put it in gear.

The thing has a 20 gallon gas tank that won't do anything for you anymore... the auto transmission is another worthless piece of weight that would be better replaced with a lighter manual transmission, or at least a 3 speed non electronic automatic. A 2 speed Chevy Powerglide would work great too.

One thing to think about: The car is inherently heavy. You may want to check into what type of suspension you have, things like that... options are the killers for weight, but you're definitely starting w/ a solid RWD chassis.

If you have a sunroof, do you really want it? Even the MIRRORS are heavy on that car, honestly. I was so amazed at all the crap on the Cougar that was under-engineered and followed the "it's heavy, so it must be good" ideology.

Good Luck w/ the project!

[Silveredwings]

Making an EV out of a car with an automagic tranny is a setup for frustration. Electric motors don't idle like the old ICE did, so the gearbox won't stay lubed. Also when you do hit the 'go' pedal, the slush box needs to spool up, waste a lot of energy and maybe cut your range in half.

From EV Weblog: Can I Use an Automatic Transmission?

There are virtually no automatic transmissions, bar the Power Glide, that have a low enough drag (or high enough efficiency) to justify having them; torque converter or not.

You cannot simply operate an A/T sans a converter because without hydraulic pressure (“engine” running ALL the time – even at idle) you can’t engage ANY gear.

The slight motor efficiency loss at low speeds (<35 MPH) of a single gear set-up more than outweigh any benefits of a transmission, any type of transmission.

See: EV Weblog: Your First Electric Car

[ModelE]

I'm trying to look around and see if i can't find a manual tranny, because 2 out of the 4 trim levels that year came with them, so there must be some around... or maybe just have a direct drive system, though that would probably be a last resort...

also, i have no qualms about tearing almost everything thats not vital out of the car. really. the rear seats, most interior trim, stuff like that can all go really easily. so, lightening it up shouldn't be a huge task...and yeah i might just remove the window motors from the doors and make a strap system, i guess like what christ had.

[Christ]

If you're that serious about losing weight in the car, just about everything can go, honestly. Check out your local craigslist and get some cheap "racing" seats... they're pretty comfy, and half the weight of the stock seats.

The manual transmission is simple, since it's RWD. Any transmission will work, and since you don't need to use a clutch pedal or clutch, the only modification you'll need to make is the transmission mount/crossmember and the end of the driveshaft. (Tranny-side yoke)

If you really wanted to, you could actually put a T56 6 Speed in there, and it would work fine.

If not, any Mustang tranny from the same time period will work, and should match up to the mount location on the crossmember.

[ModelE]

i'm assuming that you had a cougar of this same time period..did you convert it?

[Silveredwings]

Another take on automatics from a motor mfr:

Manual Vs. Automatic Transmission

Most EV conversions are manual transmissions because they are more efficient than automatic transmissions and provide greater range, require less motor torque, require no transmission cooler, and are easier to convert. The problem with an automatic transmission is that it shifts at about 2000 rpm; the electric motor is usually designed to operate efficiently between 4000-5000 rpm. Consequently, the automatic transmission is a poor choice which results in decreased range. If you buy a vehicle with an automatic transmission, you can replace it with a manual transmission. The additional cost is $150 and up depending on the transmission and used auto parts dealer. Consider trading the automatic transmission.

[ModelE]

^^ i definetly will look into replacing the automatic with a manual.