Build your own Electric Car!

Step 3: Adapter plate

You did make sure to keep the transmission, right?

We will use the car's original transmission as a way to connect power from the electric motor to the car's wheels.

The trick here is how to attach the motor to the transmission?

We will make an "adapter plate" out of a chunk of plate aluminum which has holes in it to line up with both the transmission and the end of the motor.

I pulled the transmission out of the car, and flopped it on some tagboard, then outlined it in pencil and marked all the holes.

I then took that and the motor end cap to a local machinist who is also a hot-rodder and knows way more about cars than I do.

He cut an aluminum plate to the size and shape required, complete with carefully aligned holes. The center of the motor drive shaft and the center of the transmission driven shaft need to line up perfectly.

Before bolting the motor and transmission together with the adapter plate, we need to design a coupler that will mechanically connect both drive-shafts.

Comments

[dansoffdawall]

Where can I get an electric forklift motor and batteries for a good price?

[jimramos]

I work as a buyer for a scrap metal dealer. We buy forklifts and chop them up for scrap. You might check in your town for metal recyclers instead of junk yards to hunt down a motor. I haven't read ahead to how the controls are constructed, but you will probably find some relays etc. tho help finish the project in the same visit.

[bennelson]

Start with a salvage yard for in inexpensive forklift motor. Good, cheap batteries are harder to find. That's one item that might be best to buy new. For used batteries, check with places that deal with power backups, uninterruptable power supplies, and telecom.

[dansoffdawall]

Thank you so much, this really helped me alot because I'm converting my old BMW to run on an electric power supply.

[fr334risT]

That's pretty straightforawrd , also you look just like "Tony Stark" even more with all the "Mechanical Fuzz" lol

Great Job! Looking forward to make me own very first car be an Electrict one :D

So other ppl be jelous of "Why the heck that car doesn't have a muffler or why he doesn't use gasoline!?"

Thanks :D

Joey

[montague]

Would this work the same way with an automatic transmission?

[motormayhem]

No it wouldn't work with an automatic because the torque converter always needs to be spinning to run the hydraulic pump to keep the transmission in gear. This is why you cant push start a automatic. If you loose hydraulic pressure then the transmission will be unable to shift and will not stay in gear. You might be able to pull it off with a lockup torque converter (torque converter with a clutch inside it), but you will still have problems with the transmission starting from stops because the hydraulic pressure would be too low to correctly hold it in gear resulting in a swift failure of 1st gear. The only way to make it work would be to run the electric motor at about 800 rpm when stopped with a lockup torque converter, and then when it is time to go lockup the torque converter and go. It would be a tricky process at best and running the motor constantly would kill the batteries.

[Danish M1Garand]

Back in the day this was the hot setup for drag racing. You replace the Torque Converter with a manual trans style clutch.

[jimramos]

This setup required an adapter that constantly drove the transmission pump with the clutch cover. The engine was always running just like it does with a torque converter. The only way to make an automatic work with an electric motor is with a separate small electric hydraulic pump that would keep the pressure up in the transmission. This would be additional battery drain. If you have a driver that doesn't know how to operate a clutch, no need to worry. There is no clutch with the electric motor.

[Danish M1Garand]

http://books.google.com/books?id=KKPcTD4nxBsC&pg=PA208&lpg=PA208&dq=clutch+in+an+automatic+transmission+drag+racing&source=bl&ots=CiGdgXs4zi&sig=qgNF8C5sxoVRLYzDdD7pg4jG4qo&hl=en&ei=K1m5SpraLN2C8QbP1uFi&sa=X&oi=book_result&ct=result&resnum=3#v=onepage&q=clutch%20in%20an%20automatic%20transmission%20drag%20racing&f=false

[ChemGuy45]

Did the machinist follow your stencil drawing or did he just rework all the measurements himself? The times I've gotten people to weld things for me they haven't been too accommodating.

[bennelson]

He started with the stencil drawing, and then measured, make a tin template, tested it, and then made the aluminum plate.

[matroska]

Long story short about this step: you had to fit the forklift engine to the transmission and made a custom part, right? This sounds complicated! But still an awesome project!

[bennelson]

The adapter plate to connect the motor and transmission was the most difficult part. That's why I went out to find some help on that. The adapter plate really is just a piece on aluminum plate with holes in the right places. But those holes need to be located, measured, and drilled very accurately.