# Planning 1986 Honda CRX Conversion



## drgrieve (Apr 14, 2011)

Welcome.

lead vs. lithium - lithium
Forklift motors? - possible - 144V might require modifications (eg advancing brushes / brush replacement / rewiring). Many folks on here has gone down this path.
The Open ReVolt controller? Yes [or look at a soliton jr $1800 if you can strech]
Clutch vs. clutchless? Clutch

35 mile range at 80% DOD. CRX is a very light car lets be ambitious and say you can get 200 wh/mile. 

35 * 200 / .8 = 8750 kwH.
8750 / 60ah / 3.2V = 46 batteries
45 * 3.2 = 144v 

Look at paying 1.20 to 1.25 per ah for Calb (not including delivery). Not sure on price on Sinopoly. Based purely on the spec sheets Sinoploy is a better battery but you'd have to get them from China (not aware of a USA distributor).

So 60 * $1.20-1.25 * 45 or 46 = ~ 3300 to ~3500.

Doable for an around the town car.

Note when designing your battery boxes and/or layout, leave room for paralleing the cells - so if later on you want to spend another $3500 you can double your range and power. It's better to parallel the cells as opposed to putting modules in parallel. Perhaps something to read up on if this doesn't make any sense.


----------



## youreakirk (May 12, 2012)

Thanks! What are the pros/cons of maintaining the clutch? Is it difficult to incorporate with the electric motor?


----------



## youreakirk (May 12, 2012)

Updates!

We have completely de-ICEed the car. Also we recently acquired three electric forklift motors, *amp*le (ha) power cabling, and a control system from an old forklift for FREE!

We're gearing up to start adapting the drive motor of the forklift (other two are hydraulics) to the transmission and machining the coupler.

Additionally, due to monetary/time reasons, we have downgraded our expectations. New requirements: 30-35 mph, 12 mile range.

We'd like to use some used golf cart batteries at a low cost and I hope this will get us to our goals. However, I still have a few concerns - the motor is only rated to 24v and is 7" in diameter. It is an extremely light car, but I hope the motor will be enough. It was hard to beat the price...

I've seen 24v motors used in a few conversions, *how safe is it to overvolt them? And thoughts on voltage or other battery pack specs (lead acid for cost) for the aforementioned goals? Also, is there anything we need to do before we bolt together the motor and tranny to still use the OEM spedomoter and tachometer?* Keep in mind we are high school kids with small albeit expendable incomes from summer jobs - we are trying to do a "rat rod" conversion that will get us to school and back.

We also decided to go clutchless in the interest of time and money - I can already shift (up and down) comfortably in an ICE car without the clutch.

Thanks! Any advice/comments/critiques are much appreciated!

Also, here are some pics!

Before de-ICEing


The lift!


The motors


The drive motor


The external shaft drove a gear in the forklift tranny


Power connections


Info plate


Cables!


Car tranny and clutch plate


24v control system with wrist throttle potbox for forklift


----------



## youreakirk (May 12, 2012)

The old ICE. Trying to sell this sucker, any tips?


Engine bay!


----------



## drgrieve (Apr 14, 2011)

Try cross posting the information for the forklift motors (all the info on the nameplates) to a new thread in the motor section with a link back to here.

Someone there should be able to help you. 

There is also a massive thread there all about selecting a forklift motor and the difference between rated voltage and the maximum voltage you can run them at.


----------



## hondaguy72 (May 1, 2012)

youreakirk said:


> The old ICE. Trying to sell this sucker, any tips?
> 
> 
> Engine bay!


The people over at redpepperracing.com would love to take the extra bits off your hands. Be aware that prices are not very high for these motors.


----------



## youreakirk (May 12, 2012)

Update:

Progress is being made! I recently bought a contactor rated for 48v and a 250a 48v curtis controller. The adapter plate and coupler are almost complete, and I drew a preliminary circuit diagram for the car. No idea on batteries yet, people seem to not like returning my calls.

I have a few questions: How does one wire a curtis controller? I'll post pictures of it, but B+ and B- are fairly self explanatory, but for some reason I thought the controller was just in series with the battery pack, so there would only be a need for a B- and a M-, not a B+ too... hmm.

Here's my first sketch of the basic circuitry:



My only experience with DC circuits is my high school physics class last year... I don't fully understand grounds and the whole thing may be way off but that's why I'm posting it here! To hopefully get some input...

Thanks everybody! I'll put some pics of the controller, contactors, and adapter plate/coupler up soon.


----------



## youreakirk (May 12, 2012)

Pics of controller and contactor - how do I work/wire the controller?


----------



## MN Driver (Sep 29, 2009)

You could probably push 48v through the 24v motor, just check for any brush arcing and if there is any you may need to advance the motor to stop the arcing so it can handle the higher voltage. In reality 48v may not be a problem. I've used little DC appliance motors and overvolted them without much trouble.


----------



## Ace_bridger (Nov 22, 2011)

I'm running the Open Revolt controller in my Golf with 144V of Trojan T-1275 lead acid batteries. My motor is a pukker EV motor.

I'm currently driving with no clutch and it is a pain to change up and down. I suggest you leave the clutch in. Although the motor doesn't have rotary inertia the flywheel does and it takes 5-10 secs for the motor to slow down sufficiently to be able to get into gear. A real pain.

I'm currently getting about 240-270 wh/mile so I think you'd get somewhere around 200-220 wh/mile.

The car in its current format should get 30-35 miles at 30-40 mph.

I think what you guys are doing and you deserve every encouragement. You're going to be spending a great deal of time and effort doing this and I appreciate that you're short on cash but don't over-compromise as you'll risk ending up with something that doesn't do what you need it to do.

I suggest you don't use a 48V motor controller, the car will probably move but not fast and probably not up hills.

Regarding the motor: posts the pics in the motor section on here and I'm sure someone more knowledgeable than I will comment and give you a good idea of what you can expect from them.

Good luck and well done. I'm sure your rat rod will rock!!


----------



## youreakirk (May 12, 2012)

Update: we got the wheels to spin the other day off of 12 volts - exciting! 






Now all I need is batteries, a charger, pot box, and vacuum brake stuff... and to figure out how to connect everything. I'm very confused about what kind of potentiometer to get - I can't find any info online about my controller (Curtis 1510-5201, 48V 250A). This is what it looks like: 



Here's my updated schematic:



Any ideas on if that would work / be safe? Also any tips on how to get flooded lead acid deep cycle batteries, 48v chargers or pot boxes for cheap?

Thanks!


----------



## youreakirk (May 12, 2012)

We found batteries and a charger! We have a 48v (6x8v) main pack from a used golf cart application (Trojan brand), a 48v DPI charger, and a 12v SLA deep cycle battery w/ 3 stage 1.5A charger. The 12v battery was graciously donated by Staab Battery Co. The plan is to use the 12v battery to run accessories and close the main contactor. The battery will charge when the main pack is charging (no DC-DC converter).

   

It turns out I couldn't use the controller I had purchased because I didn't have a motor shaft speed sensor, so I am reselling it on eBay (http://cgi.ebay.com/ws/eBayISAPI.dl...486432&clk_rvr_id=444171823269&mfe=sidebarpri) to pay for the Alltrax controller I bought to replace it. I got a great deal on a programmable 48v 300a Alltrax unit with a potentiometer assembly and all necessary cables.

The next things we have to work on include building a battery box, figuring out the final circuit, and crimping all our cables to the correct length. Additionally, we have to complete the third motor mount, but all the welding is done. Some minor bodywork is also necessary (we cut out big rust patches in the floor, need to weld new metal in). Oh, and vacuum brakes. Need to do those.

Any input or advice would be greatly appreciated! Hopefully this thing will be functional soon.


----------



## Yabert (Feb 7, 2010)

With that kind of setting, your car will be very slow!
Take extremely care when you will do your first test drive. 
Find a road without traffic. It won't be interesting to have many car in back of you when you will discover than your top speed is 25 mph...


----------



## Jesse67 (May 12, 2009)

Go for it, there is nothing that will give you more fun and learning than actually trying it! That CRX is pretty light so who knows it might work better than you think! What type of controller was in the forklift? It may have a higher voltage range than it was originally used at. I scrounged one from a 24V pallet jack that was rated for 36V.


----------



## youreakirk (May 12, 2012)

Yabert - Yes, I'm planning on taking over all the dead mall parking lots in town. There is one conveniently located in front of the DMV... and as far as speed goes, I realize this isn't exactly a Tesla. I saw a lot of parallels between my project and the one by the Forkenswift guys (that project inspired me to do this one). They ran a setup with used golf cart batteries (48v) and Curtis controllers ranging from 225A to 400A. Their top effective speed was 30-34 mph which is fine for me, and their top speed recorded was 45 mph. Geo Metro's and CRX's are similar in weight and aerodynamics, and I have a fairly beefy golf cart pack. I'm just trying to get it to move, and if it moves, drive it to school and back (not far or fast). (http://forkenswift.com/how-fast-far-much.htm)

Jesse - I have no idea. I'd assume it's only 24v because this was an extremely old forklift - I decided that in the time it would take me to figure out the mess of wires and cables we pulled out from that monster, I would be able to work and make enough money to buy an actual controller. The throttle was a wrist throttle with 3 forward speeds, reverse and a 1A bypass which just removed the controller from the power circuit.

The Alltrax controller is coming tomorrow, and I will have fun programming it for maximum EV grin.


----------



## youreakirk (May 12, 2012)

Hey y'all, sorry for the lack of activity here. I'm wrapping up my senior year of high school and stuff's been pretty busy. But we've gotten the car to move! We also got the attention of the local newspaper and TV station, which have photos and video respectively of the car.

St. Louis Post-Dispatch - http://www.stltoday.com/sports/high-school/john-burroughs-scholar-athlete-configures-fully-electric-car/article_32a3f236-bcba-11e2-bf35-001a4bcf6878.html

KSDK Channel 5 - http://www.ksdk.com/news/article/380710/3/High-school-senior-converts-gas-powered-car-to-electric

When I found out the Post was coming to take pictures and talk to me about the car, my friend and I freaked out and managed to get the car from having no interior, batteries, or power circuitry to a test-driveable car in 2 long nights. Although it is very jerry-rigged in its present state, it works.

It currently does not have much power because the gas cable does not throw the potentiometer arm all the way, the 40-year-old motor is old and covered in crud (planning on refurbishing it), and we have not programmed the used controller for maximum amperage. After we fix these issues the true moment of truth will come. But for now, we have a car that can do laps around the parking lot.

We're also planning on mounting the batteries closer to the center of gravity of the car (right now they're sitting in the spare tire well). We also need to install the ammeter/voltmeter and fix some general stuff like seatbelts, hazard lights, stereo, etc. But despite everything we have left, the EV grin has definitely arrived!


----------

