[stuntfreak]

Hello Folks once again!

So after driving all sorts of vehicles, I have been obsessed with EVs for the last few years. So I wanted to build a light weight super fun car to drive in and around places. Naturally I have chosen the Maruti 800. It's one of India's legendary cars that brought the automobile market up.

Anyways a good condition vehicle cost me Rs. 75,000/- I really did not want to spend time on repairs. Luckily I found a car in great shape body and chassis wise. The engine was removed but is still in good condition in case anyone wants it

So coming back to the point, I have used a 19 KW motor with a 13.2 KW BATTERY pack and a Curtis 1234 SE controller. We get 54 Nm torque constant and can probably push it to 70 NM for a few seconds with programming. Although these may not be impressive figures, the almost 7:1 Step down transmission amplifies this torque to the wheel at continuous 378 NM at the wheel until 3500 motor Rpm then switching from constant torque to constant power mode. Given that we have been able to reduce the weight of the car, this torque may end up being a fun way to enjoy this little car.

We have not achieved the exact program that we have wanted to yet on the controller in terms of torque delivery, but it's a work in progress. I had a bunch of slightly used WINSTON Prismatic LFP Cells with me, sorted them out, balanced them, and started my build.

We have used an off the shelf BMS to ensure passive balancing of the Battery Cells. I have a twin charger setup so as to cater to the charging the vehicle in 4 to 4.5 hours as the vehicle doesn't have fast charging.

I originally planned to mount the Motor on the Gearbox in place of the engine, but since I've already done that on multiple vehicles, I thought of Being innovative and used a Single Speed Step down transmission with an axle from the scrapyard, reconditioned it.

The benefit (in my case) was that I had automatically achieved longer track width.

In order to mount the Rear axle correctly, we scanned the floor pan and developed the needed 3D data to construct the necessary mounts and frames. Things went well and we have installed the Rear axle in place with Approx 98% accuracy.

Initially I though or placing all the batteries in the Engine bay, but due to space constraint and also because I would be working on something unique, I decided to place 9 cells in the Engine bay and 7 cells in the occupant compartment behind the front seats. I have a good low Center of Gravity because I shifted all cells as low as possible. And plus the space saved on top of the Batteries in the engine bay gives me the opportunity to mount the OE AC Compressor coupled to a small 200Watt BLDC Motor. (I will now have inverter AC in my car )

Bought an off the shelf Curtis Foot pedal, Mounted it in the engine bay and made brackets to operate it via the foot throttle pedal (accelerator).

The Brakes in this car are non vacuum assisted. Putting bigger rotors and calibers also seemed a little waste of time as I would have to add a Brake booster, another master cylinder, and so on. So we have programmed the motor controller for a very aggressive regen on throttle release itself. The car now runs on what TESLA calls - ' Single pedal operation ' mode. The second you release the throttle, it starts regen and slows down. So driving this car is a different experience altogether. You have to keep the throttle pressed continuously at the speed you want to drive it at. You can minutely control the speed of the car both plus and minus only based on throttle input. Brake usage has reduced tremendously thus saving on brake pad replacement cost and also good utilisation of kinetic energy for charging the batteries. We conducted a small emergency brake test and it went fantastic due to the programmed Regen.

We have also added Hill hold in the car for both uphill and down hill again because the brakes are not too great. unfortunately while braking, the car absorbs energy to charge the battery but position hold positively consumes energy to retain the position of the vehicle. This holds the car in place quite nicely but at a small cost. We will do something on this to save energy further. but at the moment if you're not worried about a few Amps being drawn to hold your car steady on a slope, its super fun!

I had recently bought an amazing Quick release steering wheel from USA during my road trip across the country. And we used it on this car. It GLOWS green in the dark too! We also installed racing seats (local. no brand) I would say they add a lot of value to the car the day I go drifting in this fun RWD, but for now it looks ultra cool.

The car has been completed mechanically. Electronically i am yet to install the Multi information display with all touch panel controls, main digital speedo, and a few things like infotainment system, speaker and so on. Cosmetically I am yet to finish the wide body kit on the car, external paint and graphics, interior carpet and new door pads, and the flat floor behind the front two seats as I have made the car into a two Seater fun RWD car.

I will update as all these changes happen.

For now the car has an estimated range of 120 kms and a top speed of 80 To 85 kmph but with nice torque to literally enjoy the car like a Go kart

We have lowered the car and put stiffer shocks too! Alloy wheels was a thought deal. The front PCD was 114.3 and the rear was 100. I had to find multi PCD Alloys of these two PCDs while checking CB, Offset, J size and so on. and luckily found a decent set. Have put on low profile tyres onto it and its good to go!

I am yet to test the car thoroughly on my track but I’m sure it’ll turn out to be fun.

I’ve made some home videos for the work done on the car step by step as below.

https://youtu.be/OEUC5oFDgac

https://youtu.be/Pci7HaCtPmM

Caption: A nice front angle of the car.


Caption: Yet another nice front angle of the car


Caption: Widebody kit is pending. but looks cool doesn't it?


Caption: Charging time.


Caption: Racing Seats and Steering Wheel


Caption:Another angle. I still have to finish the floor carpets and touch screen


Caption:I am going to mount the AC compressor coupled to a BLDC in this area.


Caption: Curtis Foot pedal throttle and drive mechanism seen.Original Battery retained and constantly charged by the DC DC Converter to retain all original 12V functions.


Caption: You can see the Curtis Controller 1234SE along with the Master Relay in the spare wheel compartment. No Spare wheel. Instead using anti puncture gel in tyres since my top speed is limited. Twin charger setup, DC DC Converter, BMS, secondary battery pack, all visible.. for now. Will be adding a nice clean empty floor board over here to put luggage.


I will be updating this thread with more information as and when possible so do check it out!

I hope you guys enjoy. !!

Cheers, Hemank

[GTO]

Thread moved from the Assembly Line to the Electric Cars Section. Thanks for sharing!

Beautiful 800, totally unique! Your car is going to our homepage today .

[srini1785]

As usual a wonderful project. I did not see the video fully but I am sure it is more detailed than the previous one. Nice job and keep going.

P.S : I wish I had not given away my M800 for cheap.

[Miyata]

Gorgeous! Return of the wizard of EV (pronounced EVE)! Will watch the attached video a in the course of the day and be back for more. Thanks for sharing.

[jothishX]

Wonderful Project. I too have a M800 catching dust. This would be a great revival for the 20 year old.
Where do you source your Lithium Iron Phosphate cells? I looked around and could find some sellers in IndiaMart. Couldn't confirm if they were genuine though. I was looking to upgrade my home automation backup system from tubular inverter batteries to these.

[adityasatish]

Originally Posted by stuntfreak

The car now runs on what TESLA calls - ' Single pedal operation ' mode. The second you release the throttle, it starts regen and slows down.

Amazing build once again. Congratulations! Just one question, is it possible to keep the option of setting how much regen you want? That would be something really useful to have, if you could set it on the fly.

[chaudh2s]

What VW model is standing behind the M800 in the first picture? Is it a VW Sharan?

[Living2Drive]

Very well done, trust you would have taken care of the 3 holes you drilled on the spare wheel tray from chaffing the 3 cables.

[rangakishen]

Hey! Looks like an interesting project. I had a few questions though.

What is the battery size (kWh or Ah)?
How are you handling the cooling, especially of the cells? And how are you monitoring their temperatures?

It seems like a great learning experience! Wish you good luck with it.

[carthick1000]

That is a wonderful build you have there. I like the idea of an Electric RWD car with a low weight and a low COG with a nice weight distribution. I am curious about the weight distribution of this car now. It is indeed smart to choose a Maruti 800 platform (Light and nimble) and not go overboard with range. 120km is more than enough for the fun drives!

I already saw one of your previous build videos few months ago somewhere in cleantechnica (or maybe in Electrek, but don't remember). That looked like a user friendly shopping car. But I am looking forward for the build to be complete and driving.

Please do share the detailed specs and if possible would be glad if you make an opensource project on github for your code. Since you already have hillhold and other such goodies installed, some of us can one day use it. I am looking for an MX-5 NA platform for a similar build. Have fun.

PS: If your home videos are this good, then I am looking forward for production quality videos.

[kiranton]

That's some next level DIY build. Forget making an electric car, I take hours to figure out the LED lights for my Christmas tree. And not to mention the time taken to untangle it.

[dajay0]

Amazing !! This is a full blown, working, road worth EV. Hats off to you. Would love to wait and watch the first road drive video.

[stuntfreak]

Originally Posted by GTO

Thread moved from the Assembly Line to the Electric Cars Section. Thanks for sharing!

Beautiful 800, totally unique! Your car is going to our homepage today .

Thank you so much for the opportunity to present on Team Bhp. There is truly no other Automotive forum like this in the Country! Hats off.

Originally Posted by srini1785

As usual a wonderfull project. I did not see the video fully but i am sure it is more detailed than the previous one. Nice job and keep going.

P.S : I wish i had not given away my M800 cheeps .

Thanks a lot. Please see the video and share frank suggestions and comments.

Originally Posted by Miyata

Gorgeous! Return of the wizard of EV (pronounced EVE)! Will watch the attached video a in the course of the day and be back for more. Thanks for sharing.

Haha. Nice name. The Wizard of EVEEEE. Pls share your opinions once you see them.

Originally Posted by jothishX

Wonderful Project. I too have a M800 catching dust. This would be a great revival for the 20 year old.
Where do you source your Lithium Iron Phosphate cells? I looked around and could find some sellers in IndiaMart. Couldn't confirm if they were genuine though. I was looking to upgrade my home automation backup system from tubular inverter batteries to these.

LFP cells I have been sourcing multiple models from multiple sources. If you need any help pls let me know. I'll direct you to the right guys. PM me.

Originally Posted by adityasatish

Amazing build once again. Congratulations! Just one question, is it possible to keep the option of setting how much regen you want? That would be something really useful to have, if you could set it on the fly.

Yes we will be having it in our upcoming GUI based touch screen with a lot more features attached. PREVIEW Attached. Do check it out.

Originally Posted by chaudh2s

What VW model is standing behind the M800 in the first picture? Is it a VW Sharan?

No its a Polo GT Tsi with 6 pot Brake calipers, drilled and slotted rotors, 17" alloys, Coilovers, Remap, and headlights.

Originally Posted by Living2Drive

Very well done, trust you would have taken care of the 3 holes you drilled on the spare wheel tray from chaffing the 3 cables.

Yes will cover in the next episode. Making the full car OEM Standard Water proof.

Originally Posted by rangakishen

Hey! Looks like an interesting project. I had a few questions though.

What is the battery size (kWh or Ah)?
How are you handling the cooling, especially of the cells? And how are you monitoring their temperatures?

It seems like a great learning experience! Wish you good luck with it.

Batteries are 200 Ah 3C cells. Cooling is a not a problem. LFP Cells are quite efficient at 45 Deg operation temp and we are monitoring Each cell PD and taking care of excess charge / discharge.

Originally Posted by carthick1000

That is a wonderful build you have there. I like the idea of an Electric RWD car with a low weight and a low COG with a nice weight distribution. I am curious about the weight distribution of this car now. It is indeed smart to choose a Maruti 800 platform (Light and nimble) and not go overboard with range. 120km is more than enough for the fun drives!

I already saw one of your previous build videos few months ago somewhere in cleantechnica (or maybe in Electrek, but don't remember). That looked like a user friendly shopping car. But I am looking forward for the build to be complete and driving.

Please do share the detailed specs and if possible would be glad if you make an opensource project on github for your code. Since you already have hillhold and other such goodies installed, some of us can one day use it. I am looking for an MX-5 NA platform for a similar build. Have fun.

PS: If your home videos are this good, then I am looking forward for production quality videos.

Thank you so much for your kind words. Will share all your concerns in episode 3

Originally Posted by kiranton

That's some next level DIY build. Forget making an electric car, I take hours to figure out the LED lights for my Christmas tree. And not to mention the time taken to untangle it.

Haha . Thanks a lot.. these are my Christmas lights..

Originally Posted by dajay0

Amazing !! This is a full blown, working, road worth EV. Hats off to you. Would love to wait and watch the first road drive video.

Thanks a lot buddy. You're most welcome to come and drive it too!

[stuntfreak]

A quick sneak peak to show development of the GUI for my touch panel VCU control and information module.

Enjoy.

[carthick1000]

Originally Posted by stuntfreak

I originally planned to mount the Motor on the Gearbox in place of the engine, but since I've already done that on multiple vehicles, I thought of Being innovative and used a Single Speed Step down transmission with an axle from the scrapyard, reconditioned it.

The benefit (in my case) was that I had automatically achieved longer track width.

Since you have a bit longer trackwidth and probably additional weight due to a custom rear axle /sub-frame, do you plan to reinforce for lateral stiffness?

Originally Posted by stuntfreak

Initially I though or placing all the batteries in the Engine bay, but due to space constraint and also because I would be working on something unique, I decided to place 9 cells in the Engine bay and 7 cells in the occupant compartment behind the front seats. I have a good low Center of Gravity because I shifted all cells as low as possible.

Did you happen to measure the weight of the whole car before, removing ICE powertrain and after putting in the electric powertrain? Would be interesting to know that in EP3