DIY Electric Car Forums banner

2001 "REV4" - Build Thread

99952 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
me!).
- 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!).
- BMS
- 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!


Garth
141 - 145 of 145 Posts

· Registered
Joined
·
309 Posts
Discussion Starter · #141 ·
Hi Pete and nice to meet you. I know it is a long thread, but dont just read the first post - there are many upgrades along the way (DC/DC converter, vacuum pumps, bigger vac reservoir). I ended up with 46X200AH LIFPO4 cells, Zilla Z1KHV controller and Warp 9 motor, and an Elithion BMS - all are still in use.

I would consider a more modern AC drive and controller (instead of DC brushed motors) - it is not a huge ordeal to maintain brushes (blow the dust from motor out 2 times a year, pulled motor out and switched brushes once since 2009) but the "direct short" aspect of DC controllers is not present in AC controllers. I think this would also lead to better overall efficiency - suprisingly it may be still hard to find high power AC motors and controllers I think (so if you can live with lower performance it is much less expensive, and much easier on your batteries). Using AC would mean a higher DC voltage and lower AH cells. I would not consider using lead acid batteries - although tempting due to lower initial costs, they are heavy/bulky, short life, maintenance needed etc...

Although some things have "moved on" - surprisingly the cost of LIFEPO4 large format cylindrical cells have not changed - virtually the same cost today as it was in 2009 (which due to inflation means some small reduction). If you can get cells from a salvage vehicle (leaf etc.) that would reduce costs. If you need 50 miles, you will need a pack bigger than mine - cold weather reduces range, and over time the range reduces as well. My pack started at about 100 kM, but is down to 50-60 now - this degradation can be minimized by adding insulation and heating pads on day 1 (ie do not charge when it is cold). I would even add an interlock to disable charging unless the cells are above 0C. The charge port should be standardized now - J1772 etc.

I would still go wtih a BMS (for monitoring cells as a minimum) - maxwell DC/DC converter has been awesome. Charger and Zilla controller are still supported by Manzanita (they have been great) but there are other less expensive options now. Hopefully you can find a quieter vaccuum pump and power steering hydraulic pump. Do put in a large vacuum reservoir - my original 4" ABS tube was too small (and lead to a scary sensation when the power brakes loose vaccuum from a hard brake and it is back to manual) - all good with a larger ABS vac reservoir.

A RAV4 has been a perfect match for my needs (ie small SUV to carry hockey stuff, kids etc, AWD in winter etc.) - that said it does not have the cool factor. It is a good daily driver, but for the amount of cost/effort to convert, make 100% sure that it is the correct vehicle for you. My 2001 has been updated with a touchscreen, android head unit etc.. but it is still a 20 year old vehicle - if you can find something newer it would be better. A lot of money to convert, so using a newer donor would make sense. I dont think they still make standard transmissions in newer RAV4s (at least not available in Canada) - manual transmissions are a lot more popular in the UK so hopefully you can find one.

All the best on your conversion - make sure to add a build thread!

Garth
 

· Registered
Joined
·
697 Posts
Oh-oh - big problem! Which motor will fit?

Oh-oh - big problem...

Look at these pictures - top view:


Manual transmission is on the right, AWD transfer case (top) bolts to the transmission, and has a rear drive shaft exiting toward the vehicle rear (not shown).

and side view (zoomed in):



The manual transmission bell housing is plenty wide, but the transfer case (remember, this is AWD with a transverse motor mount) sticks out and really limits how big of a motor can fit.

I was hoping to build a rocket, and maybe use a Warp 11 or Warp 11 HV motor, but this clearly is out of the question. My fallback was to settle for a Warp 9, however even this is questionable.

The Warp 9 diameter is 9.25" - I have just enough room for 4", 19/32, equals 9.1875".

This is too close to call - can anyone confirm that the Warp 9 is exactly 9.25" diameter?

I thought about pounding in the differential cover on the transfer case, but it looks like some sort of composite and probably will not bend nicely...

Now I know why no-one converts AWD (and here I thought it was just the wasted range).

Any ideas?
A Nissan LEAF EM57 motor is very small and compact. Not sure if it will fit nicely in there with the t-case however. There is a lot of aluminum casting that could be cut off to slim it down also. See the photos below:







 

· Registered
Joined
·
1,320 Posts
A Nissan LEAF EM57 motor is very small and compact. Not sure if it will fit nicely in there with the t-case however. There is a lot of aluminum casting that could be cut off to slim it down also. See the photos below:







That wouldn't clear the transfer case unfortunately, the max was around 8" but you could build a tunnel to move the motor over if the motor were short enough, though I don't believe a Leaf motor is.

I've wanted to convert a Rav4 for years though I'd go twin motor for AWD but if I kept the trans I'd fit something like a VW GTE electric motor inside the bell housing in a water cooled housing, no clutch and probably only keep 2nd and 4th gear, reduce resistance etc in the gearbox. But there a fair bit of machining work.

cheers
Tyler
 

· Registered
Joined
·
11 Posts
That wouldn't clear the transfer case unfortunately, the max was around 8" but you could build a tunnel to move the motor over if the motor were short enough, though I don't believe a Leaf motor is.

I've wanted to convert a Rav4 for years though I'd go twin motor for AWD but if I kept the trans I'd fit something like a VW GTE electric motor inside the bell housing in a water cooled housing, no clutch and probably only keep 2nd and 4th gear, reduce resistance etc in the gearbox. But there a fair bit of machining work.

cheers
Tyler
Thanks Electric Land Cruiser for posting the pictures. Now I know it's not too long and I can run reduction gears between the motor and transmission. Which will push the motor over enough to clear the transfer case. Thankfully I work in a shop with machining capability.

Tyler, removing unnecessary parts from transmission is possible? I was thinking that way also. As for motor choice the used EV selection is limited in Canada. We have only had Leaf and Tesla for any length of time, most of the others didn't have a presence here until recently. I want to use an existing EV system for reliability and hopefully simplicity. For the money I have to put into this I could have bought a compliance Rav4EV from California back in 2019, but no AWD. Current RavEV prices are ridiculous for a 10 year old car. But we don't do this for saving money do we, it's for the challenge.
 

· Registered
Joined
·
1,320 Posts
Thanks Electric Land Cruiser for posting the pictures. Now I know it's not too long and I can run reduction gears between the motor and transmission. Which will push the motor over enough to clear the transfer case. Thankfully I work in a shop with machining capability.

Tyler, removing unnecessary parts from transmission is possible? I was thinking that way also. As for motor choice the used EV selection is limited in Canada. We have only had Leaf and Tesla for any length of time, most of the others didn't have a presence here until recently. I want to use an existing EV system for reliability and hopefully simplicity. For the money I have to put into this I could have bought a compliance Rav4EV from California back in 2019, but no AWD. Current RavEV prices are ridiculous for a 10 year old car. But we don't do this for saving money do we, it's for the challenge.
@94Tracker I'm very curious of your plans, would you mind starting your own thread so we don't pollute Mr gdirwin's thread here? Love to chat with you there.

cheers
Tyler
 
141 - 145 of 145 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top