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2001 "REV4" - Build Thread

101383 Views 144 Replies 27 Participants Last post by  tylerwatts
Formally introducing myself - I am an Electrical Engineer working in power
systems (wind farms, HVDC links, machines etc...) and specializing in
computer simulation. I also have a bit of auto-mechanic experience (I
have owned a 1975 F250 4x4 Highboy since 1983).

I have been a long time lurker here - thank you all for the phenomenal
support/information - this is a great site!

I am also fortunate to have my nephew (Derek) helping me on this - he is
18 and will graduate from high school this year. He has an aptitude for
taking stuff apart and fixing things, so this is a win-win situation. I enjoy
working with him, and his help will be appreciated. We hope to work every
Saturday and maybe one evening during the week. I have 2 boys (6 and 8)
who play hockey etc... so I am already pushing the limits of my spare
time - this will be a very slow build...

I recently saw Rob's (RKM) Red Miata - this lit a bit of a fire, so here we go...

My overall plan is to convert a relatively new vehicle (>2000) and to make
an EV that works just like its ICE counterpart in all ways - it will have
power everything, heated leather seats, full trunk space, air conditioning,
AWD etc... The plan is to demonstrate that you do not have to give up
anything to drive an EV (in fact it will be faster and better). Of course this
will not be a cheap build, nor will it be a super-efficient low kWH/kM build,
but it will be a very driveable car I will use as a daily driver in all seasons
(also more on this later).

I really only need about 50kM of range per day, but given winter
conditions in Winnipeg, and my desire to not push any equipment close to
its ratings, I will try to squeeze in more batteries/range than what is
really needed.

I finally bought my donor and started work:
2001 Toyota RAV4, 135,000 kM, AWD

I choose the RAV as it is a family car (would love a light 2 seater
convertible but with a family of 4 it is a no go), has some height/weight,
plus it has a history/reputation for EV'ers (stock RAV4 Ev etc...). also
considered a Ford Escape or Honda CR-V...

Everyone loves pics (although this is only the stock car so far):

Yeah - I know - the big sticker on the hood has to go. You should have
seen the car before - it had "all available Canadian Tire options". I bought
an OEM leather interior kit, as well as some carbon seat heaters for driver
and passenger with 5 position dial (I can hear the groans from all the EV
purists who have scrimped on weight/features etc... to get max range!)

My "REV4" EV Conversion Plan (please - all comments/suggestions/feedback welcome!):
- Warp 11 (or maybe even Warp 11 HV?) motor
- Zilla HV 1K or Soliton1 (not decided yet)
- SE or TS LFP batteries, probably 65*100AH (more if there is room - more on this later)
- keeping the 5 spd manual transmission, have bought a new clutch

Note that the motor and controller are likely more than the stock
clutch/transmission/AWD system can handle - I figure that equipment that
is rated for higher duty conditions but driven "soft" will last longer, not
heat up etc... (definitely an engineer talking - over design it). I love the
power however, so will start with the max controller amps limited, then
increase it until everything feels shakey, then back it down a bit...

If the Warp 11 HV motor receives good tests reports, then it seems like a
no-brainer for the cost - I will use a high voltage and as many batteries
as I can fit.

I plan to put the majority of batteries under the hood (on top of the DC
motor, manual transverse transmission and AWD transfer case). There
also is room under the rear of the car where the gas tank used to be (2
smaller boxes) - keeping the 4x4 definitely adds a penalty here as the
rear drive shaft cuts everything into 2. I do not want to fill up the
trunk/back seat with batteries though.

The batteries are a big pain (a low-height LFP battery that can stick under
the floor pans would be killer) - in reality I only have about 11" to work
with (which means TS or SE 100AH batteries, which are 8.66" high - once
you add the BMS, enclosure, insulation and heating pads, this doesn't
leave too many options. There are also the new SE 240Ah batteries (6.73"
high, 17.72" long, 2.8" thick) but that massive 18" length just won't match
up with the room I have in the car.

Horizontal placement of the batteries would also work, but I have been
told by SE that this is not recommended and would void warranty.

I think I can fit about 20kWH of batteries into the 3 boxes - I will pull out
all the junk in the way before ordering batteries though (maybe a
reasonable priced A123 deal will come along between now and then?)...

One non-logical aspect to my choices are using a 1000Amp controller with
100AH batteries - 5C would be a huge draw (perhaps too much?) so higher
AH batteries would be a better fit - they are too darn tall however (or too
wide for the 240AH) so I am somewhat torn/stuck. All suggestions
appreciated here - what would you do?

I am undecided on many other parts - will be deciding soon though. I will need:

- electric vacuum pump for power brake booster (Rob/RKM showed me a
pump that was enclosed inside of the vacuum tank - that made sense to
- electric power steering pump (no-one in Canada has a 2000-2005 MR2
Spyder pump - trying hard to find one in US for a decent cost - let me
know if you find one!)
- hydraulic pump/heater for interior heat (will keep stock heater core and
fan/controls - I don't like the idea of electric heaters inside the interior
heater core)
- 1000 Amp contactors/breakers/fuses?
- battery heating pads (it gets to -40 deg in Winnipeg for a few weeks
every year and I have to get to work!).
- charger (I want a dual voltage 120/240 charger - 30 Amps would be lots)

I plan to pull the motor etc... soon (1 or 2 weekends from now) - I will
take careful measurements for the motor and batteries and make some
decisions then...

I have never done this (and definitely respect the people who have) so
please - all comments/suggestions appreciated!

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Since you aim for high voltage you will never pull 5C from the pack. 1000 amps controller means 1000 amps on the motor side, not the battery. If you go for 65 cells ( 208V nominal ) you will probably pull 300amps during acceleration, which is perfect 3C for 100ah cells. Cruising will be about 100amps, which is perfect 1C rate. Still, try to pack as many cells as possible to add voltage if you stick to 100 ah cells, to reduce current.

That sine wave is fine, I had same exact signal on my Mazda. You need 36 tooth wheel, which may need one gap ( one tooth removed ). See my Protege build thread, I have pics of the tooth wheel I made for RPM signal.

You will need a shop manual, get one, it has all these signals documented, helps a lot...

Good luck, seems like a very interesting and ambitious project.

I had same goals with my Protege, no compromise EV, turned out well, but being in warm and flat Florida helps a lot :D, you will have more challenges in Canada, but its all doable.
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Hi Dave:

The ECM even has wiring to the ABS braking system and A/C system (in addition to the airbags) - not sure if this is only for the check engine light/diagnostics, or if there is more to it. I think I will plan to keep the ECM for now.

I did spent some time mapping out all of the sensors and which trouble codes light up - I was originally planning to fake out each sensor with resistors etc... (so the CEL light would stay off), but it got too complex (the 1 or 2 wire sensors would be easy, but some sensors have 4 or 5 wires, such as MAF etc...).
I've gone thru all same steps with 2003 Mazda, analysed every sensor, etc. Don't bother simulating all sensors, its a waste of time. All you need is the RPM signal from the engine, all other engine sensors can be cut off. All transmission sensors ( VSS mainly ) should remain. ECU should remain, there is more benefit in keeping ECU than in removing it, why remove it if its not causing any troubles?

As for CEL light, don't even bother, just cut the CEL light wire at the instrument cluster harness and use it for other EV purpose, like controller fault light in Soliton1, works great....
In addition to RPM, another OEM engine sensor I used was coolant temp sensor. I epoxied the sensor into one of the lift holes in Warp9 and added 5k trimpot in parallel to the sensor to lower its resistance, to allow meaningful range on the temp gauge, since EV motor has much cooler temp range compared to ICE. Now I can look at the temp gauge and see if my motor is overheating, nice and simple :)
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