Aussie EV Autocross Special

Over the Christmas break I made a couple of minor improvements.

I added a heat shield between the motor and controller. Last time I competed the heat was rising from the motor into the controller and was making me nervous. If was a rather hot day, but this is Queensland so hot days are not rare. The heat shield is really excellent so I am confident this will mostly take care of the issue except if it is an exceptionally hot day (by QLD standards >35c). But I plan to also install a fan to extract any stray heat from the engine bay.

I modified my rear lower control arms (2 on each side). I added some thread so I can adjust them in and out to modify the rear alignment. This gives me some camber and Toe adjustment. It can't be adjusted on the car, at least one end of each arm must be disconnected so it can be twisted in or out.

The next event is a Motorkhana on Feb 12 followed by a couple more in March. But I am really aiming for a good result in the Khanacross April 9th.
 
galderdi said:
Over the Christmas break I made a couple of minor improvements.

I added a heat shield between the motor and controller. Last time I competed the heat was rising from the motor into the controller and was making me nervous. If was a rather hot day, but this is Queensland so hot days are not rare. The heat shield is really excellent so I am confident this will mostly take care of the issue except if it is an exceptionally hot day (by QLD standards >35c). But I plan to also install a fan to extract any stray heat from the engine bay.

I modified my rear lower control arms (2 on each side). I added some thread so I can adjust them in and out to modify the rear alignment. This gives me some camber and Toe adjustment. It can't be adjusted on the car, at least one end of each arm must be disconnected so it can be twisted in or out.

The next event is a Motorkhana on Feb 12 followed by a couple more in March. But I am really aiming for a good result in the Khanacross April 9th.

Great idea with the heat sheild how are you charging your pack now?

Cheers Kiwi
 
I am still charging 6 cells at a time using a hobby charger. It works fine for most of my needs. But I have a 2 day event coming March 25/26. So I will need a faster solution for that weekend. I am about to purchase a Thunderstruck charger which should do the trick. But it is coming from the USA so it will take a while to get here and then I will need to rig up the relays etc. .
 
oatnet said:
galderdi said:
Hillhater said:
I admire your aproach and results you are getting Galerdi, but if it were me i would certainly be getting some data logging onboard to monitor syslem performance, motor and battery ,volts, Amps, temperatures, etc.
Some of the better controllers have this built in, but stand alone data loggers are not expensive these days, and software for download analysis is freely available online.
Even just using a CA unit would give a lot of useful data, peak amps, max/min volts, rpm etc...
http://www.ebikes.ca/product-info/cycle-analyst.html


Wow that does seem like a good product and price. I have sent a message to their local distributor. I will certainly get a hold of one (Assuming they don't jack the price up by 1000%)

Yes! I'm glad Hill finally got the CA on your radar, because the (3) times in this thread that I have specifically recommended the CycleAnalyst to you for that purpose didn't seem to sink in. :lol: Must be my American accent.

I am looking forward to someone else telling you that your Curtis controller is too weak to drive a 9" brushed motor, and that a $75 power supply will charge your pack in hours instead of days, so you can start enjoying what your build really has to offer. :mrgreen:

Oatnet, you were right again. The controller was too weak to drive the motor. At least I am man enough to admit when I was wrong. My resistance to accept the facts was more about budget than anything else. It has been a painful experience from a financial point of view. But I am confident 2017 will provide some excellent results now that I am running the Zeva 1000amp unit.
 
Here is a summary of my 2016:

Feb 7th was a motorkhana. The car wasn't too bad at this event although I hadn't turned the controller all the way up and the controller delay was a pain making it a handful to drive. I have since turned the controller all the way up and removed the delay.

Feb 21st was a khanacross. The old AGM batteries were not up to the task. I was only able to complete 60% of the event. I also destroyed two of the AGM batteries which split their seams and were venting acid out the sides. The ackerman angle was still wrong at this point so the car was fighting itself in high sped corners.

March 19 was a motorkhana. I had swapped over to the Lilo batteries from a chevy volt. The batteries were fine but I did not have a method of charging them. I travelled 10 hours each way knowing I only had 145volts. It only lasted 20% of the event. But was otherwise running fairly well.

April 24 was a motorkhana. I only managed 1.5 runs before I broke my brakes (broke the weld connecting the pedal to the master cylinder). I managed to complete the second run using the handbrake but decided it was not a great idea to continue for the rest of the day.

May 25 was a Khanacross. I had a loose connection for the first 2 runs. The car actually stalled completely on the second run. I found the issue and the car was promising for the remaining runs of the day. I managed 2nd in class and 10th outright. After the event I realised the brushes were seized in place and the motor was beginning to arch.

June I wound up the controller to the max and solved the issue of the brushes. So I am confident the results will improve in khanacross. Motorkhana will always be challenging for this car as it is wider than the other motorkhana special cars so it is at a disadvantage in most motorkhana courses. The torque of the electric motor will compensate for the width to some degree but whether it is enough is yet to be seen (Starting with this coming Sunday).

Aug 7th was Rnd 3 of the QLD motorkhana championship. The car was OK but I was not in the best mindset as I was not seeing the performance I was expecting. I only managed 18 from 20 competitors due to a lot of mistakes.

Sep 4th was Rnd 4 of the QLD motorkhana championship. I was doing fairly well through the day. But on the last run I had a significant failure of my left rear suspension as a side effect it blew the main fuses. Unknown to me it also blew the pre-charge resistor. Then after replacing the main fuses I attempted to start the car (without a pre-charge resistor) which resulted in blowing out the controller. I still managed 8th from 18 competitors.

Nov 6th was a Khanacross but I hadn’t managed to complete the conversion to the new Zeva controller so I was not competing at this event.

During October and November I replaced the rear suspension control arms and replaced the controller.

Nov 27 was the Vice President’s Motorkhana. This was my best result for the year managing 6th outright and beat 4 Clubmans and 8 out of 10 Porsches. The geometry of the rear suspension was not quite right, although I don’t think that impacted the results. I did have issues with the controller reverting to it’s default settings between each run. I think the resetting would have impacted the results as I was limited to 500 amps instead on around 1000 and the controller was defaulting to a slight throttle delay.

In December I removed the lower rear control arms and made them adjustable by adding some threaded rod. This allows some finer adjustment of the rear camber and toe. I have also re-wired the controller system so I can retain the controller settings for an entire day.
I achieved a 1st in class for the khanacross season and a 2nd in class for the motorkhana season (yes there were others in my class). These are reasonable results considering it was largely a development year.
 
Yeah. I have high confidence for the next khanacross in April. I should also improve in the next few motorkhanas but it will be hard to take 1st or 2nd places in a car so big.
 
My next event is a come and try motorkhana on Feb 12 at Willowbank. If anyone is in the area feel free to come and take a look. Spectators are free and I will have a spare helemet so I can take passenger rides.
 
galderdi said:
My next event is a come and try motorkhana on Feb 12 at Willowbank. If anyone is in the area feel free to come and take a look. Spectators are free and I will have a spare helemet so I can take passenger rides.

Bugger wish I lived closer mate would be into that in a heart beat

Cheers Kiwi
 
Just a short swim away.... swim away, swim away, swim away, in the jungle the mighty jungle.......
 
This weekend I did the final alignment on my rear suspension using my newly adjustable lower control arms.
I then tackled my BMS.
I neglected to realise they needed IDs configured when I originally installed them. Because I mounted them vertically next to each other I needed to disassemble them to access the dial to configure the IDs.
I can now see the voltages of each individual battery etc.
I now need to wire up my new charger.

20170128_182509.jpg

20170128_182453.jpg

20170128_182433.jpg
 
looking great man, i am in town feb 12th if i have time i'll try drop in to willowbank and catch you!
 
sketchism said:
looking great man, i am in town feb 12th if i have time i'll try drop in to willowbank and catch you!

Awesome. I should be able to take you for a run or two if you can make it on the day. Any photos you could catch would be very welcome, I seem to struggle to get action shots.
 
CAMS have banned all remote control aircraft from events under their governance. So it will need to be outside the event boundary. I have a friend with a decent one so we'll see what comes of that. Or maybe I should just try and get the Batt mobile airborne :)
 
I just purchased another camera. This one does the full 360 degrees. IT should provide some great angles
 
It ended up being 43 degrees on Sunday so the event was cancelled. I think it was a wise move.

But a few of us went out there anyway for a casual test and tune. My car went quite well. It was the best performance I have managed. I got it up to 120kmph and 0-70 was very exciting. But my rear wheel alignment is still shot. At any speed over 70kmph it was downright dangerous. I had to fight to make it track straight. The other guys had proper wheel alignment gear so I took some measurements. I need to set it back to neutral camber and adjust the toe in (its currently significantly tow out).

Here are some videos from yesterday:
[youtube]Ifn0MraoOqY[/youtube]
[youtube]R29oHcDjqsM[/youtube]
[youtube]iBq_FRonaF8[/youtube]

360 degree
[youtube]JrBSLbH-KQU[/youtube]
[youtube]_UmPyZ9IsMg&t=12s[/youtube]
[youtube]hCtxdOWFNSs[/youtube]
[youtube]OXndLk-KasA[/youtube]
[youtube]gyJqg8RN2Qw[/youtube]
 
I have finally managed to get a real charger for my car. So I am going from a 3 week turnaround to around a 3 hour turnaround. Yay!!!!
 
Its a Thunderstruch TSM2500. Although the specs indicated it would handle 20 amps I was expecting it to throttle back. But to my surprise it is quite willing to put out the full 20 amps. in 20 minutes it had pumped 0.5kwh back into my pack.

I think I will generally set it to 10amps as everything was getting quite warm at 20amps. But knowing I can tap into the 20amps occasionally makes me rest easy. It means I really can have 2 drivers at an event and even plugging it in for 10 minutes here or there will make the difference between completing the day or not.

I've installed the charger in a plastic storage box for easy transport. Then I added an audio socket in the side of the car wired up to the charge enable (12v) output from my BMS. So to charge I just need to:
  • plug the charger into the wall
  • plug the DC lead into my batteries (via an Anderson plug)
  • plug the charge enable plug into the car
  • and set the controller in "Stationary" mode (which sends the charge enable)

I also added a cigarette socket in the side of the car wired up to my 12v aux battery. I will be using this for fans to cool the motor and controller and also as an input for a solar panel to prolong the charge in the aux battery in the hope to avoid swapping it mid way through the day.
 
A quick reminder. My next motorkhana is this Sunday (March 12) at the back of the Willowbank drag strip. If anyone is in the area feel free to pop by, spectators are free.
 
My weekend was great although a little stressful at the end. Our club had a come and try Motorkhana with a decent turn out. I took my new slicks but couldn't get motivated to swap them on. Plus they are expensive tyres to waste on a come and try event. The car went really well. I set it on 750amps for most of my runs. That was plenty of power to spin the wheels. I was starting to get the hang of feathering the throttle. My adjustment of the throttle has made it much more controlable. 3 of the 5 motorkhana specials dropped out after a few runs. 2 were due to mechanical issues and 1 due to a driver's previous health issue. The other special was quicker than me, as expected. Not because of power but because his car is smaller, lighter and more nimble. I will gain a little at the next event by swapping to my new tyres but I doubt I will beat him (for the same reasons). Hence why I am starting my next project. I am fairly confident I beat all the road cars so I would have come about 2nd if it wasn't a come and try day. But then, just before the last test, my car suddenly died. I checked all the usual causes but couldn't see anything obvious. Eventually we pushed it on the trailer and I called it a day. I sorta hoped the trip home would cool it off and it would be OK again, but that wasn't it. Then I got to thinking the SOC was getting sorta low by that stage. I had run it lower with the old controller but this is the lowest I had run it with the new controller. So maybe I had exceeded the controller threshold. So I went to connect the charger and realised the controller was set to "Stationary Mode". So I switched it back to "Running Mode" and it worked again. I will try and replicate this scenario this coming weekend to understand if my theory is correct. But I was quite concerned while it wasn't working because I was unsure if I would make the next 2 events on MArch 25/26 in Gladstone. But it has all worked out.


Oh and the rear alignment is now great. Much more stable than the Feb tests. Here are the videos from Sunday:

I am not embedding them all just to save space and scrolling.

External view:
https://www.youtube.com/watch?v=_uXDdvUHg6Y

With GPS:
https://www.youtube.com/watch?v=asit5SQQSZc
https://www.youtube.com/watch?v=xa2w1gjgRIQ
https://www.youtube.com/watch?v=c3y_nly2_mw
https://www.youtube.com/watch?v=YYa9lguj_I4
https://www.youtube.com/watch?v=XnaZaJxcd5U
https://www.youtube.com/watch?v=KD0WnfrfIDc
https://www.youtube.com/watch?v=Tf6WaTz6M04
https://www.youtube.com/watch?v=4QpN9s1WFsM
https://www.youtube.com/watch?v=6blm59_tczY
https://www.youtube.com/watch?v=DGEAs0eIJkI

360 degree:
https://www.youtube.com/watch?v=CUJe4m1k4ZE
https://www.youtube.com/watch?v=ojP3m5nVLEY
https://www.youtube.com/watch?v=L46Kg-hptzU
https://www.youtube.com/watch?v=-3eUchGXwdM
https://www.youtube.com/watch?v=eZBPCqvG9sU
https://www.youtube.com/watch?v=ABUpOKKD9W0
https://www.youtube.com/watch?v=9mYojBCwMa0
https://www.youtube.com/watch?v=BclkWfzSe9A
https://www.youtube.com/watch?v=2RhTYfb5e_0
 
Just got the results from Sunday. It is about what I expected.
• Every time was my personal best.
• I only placed 7th outright because I missed 2 tests (I didn’t even realise I missed the one earlier in the day).
• Of the tests I completed I came 5th once, 4th twice and 3rd twice.
• Of those that beat me only one will be heading to Gladstone. This means I should move into second place for the club championship.
• On average I was roughly 1.5 seconds off the pace (behind first place). I don’t think I will be able to pick up the full 1.5 seconds but my good tyres will get me fairly close in Gladstone. Plus more feathering of the throttle will help too.

It is a bit of a stretch for me to expect to beat the fastest cars outright because mine is a bit bigger and heavier. But attrition plays a big part, so if I can be consistant through the year I can still place well in the motorkhana championship.

Really though the car is much better suited to Khanacross. So I am mostly focused on that championship for 2017 and I aim for a more serious crack at the motorkhana championship when I build my new car.
 
Nice work mate .
Just a thought after watching your videos its seems that your steering can't keep up with the car, I could be wrong.
There are inline power steering systems that could reduce your steering wheel turns.
Just a thought mate.

Cheers Kiwi
 
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