1 (edited by rmcdaniels 2016-12-24 01:16 PM)

Topic: "Racing" the Duff Beer Electric Car

Just a little background; after our win at Barber, it was time to make the Duff car faster and move it to A or to find another ride. While we love the Duff car and it's served us well for 7 years, it's time to move on. See you around Duff car:


After some team discussion, we decided to build a cheaty fast class A car, but we were short of time before the CMP fall race, so we thought that we'd do something ridiculous for a change. We've always admired teams like Speedycop, NSF, Sputnik, and many others who bring hopeless, but entertaining cars, and we've never done anything like that, so we figured we'd give it a shot. 

After a quick review of local Craigslist ads, we found a 1981 Jet Electrica 007 (that was actually a real car, Google it), which was easily the most hopeless car that we'd ever seen. Ricky and I dragged it back to the shop:


Other than it's innate horribleness as a car, it wasn't in bad shape. We fixed a few minor mechanical and electrical gremlins, and it was ready to go. Ricky tagged it and I drove it around town for a while. This plan might actually work.

Then the crazy part started.

To power it, we needed batteries, and Sam's Club deep cycle 12v batteries seemed like the cheapest option. We'd need 10 of them (120V DC) to run the car for 18 or so miles, and we'd want extra sets so we didn't have to wait for hours in between runs. After cleaning out 8 or 9 Sam's Clubs in 2 states, we collected 31 batteries (needed one extra to run the 12v electrical system).


Then we'd need to charge them. That required 20 chargers, or more. I started ordering chargers off of eBay, and just kept bidding. There was no way that we'd power that many chargers (a 20A battery charger pulls 5A of AC) off of the sketchy CMP electrical power, but the RV had a 10KW generator that would power 14 of them, while Sam's Club had a cheap generator that would power the remaining 6, so we ran two generators all weekend:


We figured it would be slow, so we attached kid's bicycle safety flags to it so everyone could see it and stayed full track right at all times:



Ricky's first stint went okay, but my stint was a disaster, overheating the motor and killing the batteries in a couple of laps. We quickly determined that racing was different from street driving. You are on throttle a lot more and the motor never gets a chance to rest like it does in street driving. This leads to heat buildup and takes you out of the race. Eventually we worked out how to keep it on track. We could only go for 6 laps on a set of batteries (3 laps, 20 minute cooldown, then 3 more laps), and had to adhere to the following rules:

Never let it go under 30 MPH
Never let it go over 40 MPH
Never use more than 100A
Never use the brakes

That seemed to keep it running, albeit slowly and for short stints. Then we just had to swap out 1700 pounds of batteries and get the old ones on the chargers so we could do another 6 laps. That seems reasonable.



Once we got it sorted out, we came up with a goal for the weekend, which was to double the previous lap record for an electric car and to not get towed off track, so we needed 52 laps and for the 35 year old electric drive system and vintage Chrysler L-body running gear to work flawlessly. Again, that seems reasonable.

By the end of the first day we had a smoothly operating system and crossed under the checker with 27 laps, a new electric car record. By the end of day 2 we crossed under the final checker with 55 laps and drove it on the trailer.

I have never worked so hard or spent so much or been so happy for 55 laps.


Phil and Jay put us in a new class, Class E, which we won by 55 laps, and awarded us the IOE-e, which comes with a free entry to the next race if we bring an electric car.

After some discussion, it looks like we'll be back at Barber with the electric car. Preliminary goals for the next race are:

Be able to go 70 MPH in race conditions
Double the previous record, so 110 laps or better
Do not get towed off
Pass another running car on track (other than the minivan that was going backwards, on fire, and driverless, I mean, technically it was running on track and we passed it, but we really don't count that one)
Post a lap time that is not the slowest time of the weekend.

We'll see you guys at Barber.

Everybody grab your brooms, it's shenanigans!

2 (edited by Drdanteiii 2016-09-21 06:32 AM)

Re: "Racing" the Duff Beer Electric Car

Awesome.  Well done.

Charging 20 batteries at a time from gas generators with minimal pollution controls running constantly is exactly what Al Gore had in mind.

I wonder if you calculate MPG from how much fuel the generators burned vs your track mileage  what you'd get.

consistent with Duff Beer theme...

The Roto-Racer '89 Merkur:  If it ain't rusting, It ain't racing.

'14 Real Hoopties of NJ: Judges Choice

Re: "Racing" the Duff Beer Electric Car

As I've said before, you guys are_the_ best slow car team to share a race track with.  All of you are excellent with use of the mirrors and giving point-bys.  You are very predictable, and I'm never concerned that you will do something stupid, like a few others that I won't name.  I wish you well in your future electric car endeavor.

Team Super Westerfield Bros.
'93 Acura Integra

Re: "Racing" the Duff Beer Electric Car

Once I get back to the east coast I'll be glad to offer you some generator time at the track to charge batteries. I have a collection of military generators that would have no problem powering a charger farm.

I also have an inverter/charger setup (Schneider XW6048) that will charge a 48v string of batteries. It will do 100 amps on the charging side. The charger is programmable for any battery chemistry and has temperature sensors to prevent cooking the bats. If you run 12 batts in the car in the future you could segment them into 48v packs and charge all 3 packs in parallel at once.

Charging the batteries in banks will be better to keep them balanced. You want to make sure each battery has the same SOC when it goes back out on track.

Looking forward to seeing the next revision to the vehicle!

Re: "Racing" the Duff Beer Electric Car

I fantasized about doing something like this. It's harder than I would have imagined. Thanks for everything (building, sharing, steering me off this horrible path, keeping Lemons lemony, etc.).

M-Ark-2 Vodden 2012; Babelfish Pointless 2013, More Pointless 2013 (Organizer's Choice); Lamborarri Vodden 2013 (P9), Freeze 2013 ; Royal Mail Vodden 2014; Can't Am Freeze 2014; Iron Flutterby Vodden 2015; Baltimorons Loudon 2015; XX Racing (crew) Freeze 2015; Ernie Pointless 2016; WINsome/Scotsmen Discomfort 2016; D-Spec FTW Vodden 2016, Sweat 2016

Re: "Racing" the Duff Beer Electric Car

I have never worked so hard or spent so much or been so happy for 55 laps.

Sometimes even just 1 lap is the sweetest, most glorious lap ever to be had.

Great writeup and super happy you were able to meet your goals!

Reading this, now I understand why there are water-cooled electric motors. Wonder if you can some up with a cooling setup for the electric motor, similar to what the Lemons Rally participants did for their transmission--  maybe wrap some tubing (metal or other) around the motor and use a pump to circulate water across it? Maybe an axle-driven pump so there's not another electrical load wink

Re: "Racing" the Duff Beer Electric Car

Drdanteiii wrote:

I wonder if you calculate MPG from how much fuel the generators burned vs your track mileage  what you'd get.


Everybody grab your brooms, it's shenanigans!

Re: "Racing" the Duff Beer Electric Car

Thanks for the info and pictures. Keep up the great work.

I was curious how Formula E does their cooling - found this.


12X Loser - Delinquent Racing - '86 TRUMPACO Merkur - '17 Arse-Sweat, Sears Pointless, '16 Pointless, Vodden, Arse-Sweat, Button Turrible, Arse-Freeze - 2015 Vodden, Arse Freeze. '96 Ford Taurus SHO Skunk - '17 Vodden (Hope for the Future award - not me, the rookies), '15 Pointless, Button Turrible.

Re: "Racing" the Duff Beer Electric Car

rmcdaniels wrote:
Drdanteiii wrote:

I wonder if you calculate MPG from how much fuel the generators burned vs your track mileage  what you'd get.



Hats off to Duff for a fantastic job of executing a fantastically bad idea. I can't wait to see V2.0 at Barber!

RetroRacing-1973 Super! Beetle: 2010 CMP Fall-Judges' Choice, 2014 Barber-DFL and I Got Screwed!, 3X- You Talk Shit Better Than You Race (YTSBTYR) Award, 2017 NCM- IOE (thanks, Speedy!)
Now available west of the Rockies as... Nine Finger Drifters- 1982 te72 Toyota Corolla Wagon (it's got a HEMI!)
My one man show: G. D. Yo-Man: No! YOU Ams Da A&&hole! (coming soon to a racing venue near you)

Re: "Racing" the Duff Beer Electric Car

You mentioned the weight of the batteries.  How much does the car weigh with a full battery setup?

Also, do you have a different onboard fire extinguisher?

LemonAid - Changing kids lives one lap at a time.

Re: "Racing" the Duff Beer Electric Car

The car weighed about 3700 pounds as raced.

Fire extinguisher was a regular small fire bottle, although that will change when we move to lithium-ion.

We'll need newer and better technology next time. Thankfully major manufacturers have been making EV's for several years now, so salvage yards are pretty well stocked.

Everybody grab your brooms, it's shenanigans!

Re: "Racing" the Duff Beer Electric Car

And now one salvage yard is slightly less well stocked. I got back from Fayetteville today and found 16kWh of creamy lithium ion goodness waiting at the shop:


Everybody grab your brooms, it's shenanigans!

13 (edited by billybobster 2016-09-22 07:39 PM)

Re: "Racing" the Duff Beer Electric Car

Nice score. What did it come from?

12X Loser - Delinquent Racing - '86 TRUMPACO Merkur - '17 Arse-Sweat, Sears Pointless, '16 Pointless, Vodden, Arse-Sweat, Button Turrible, Arse-Freeze - 2015 Vodden, Arse Freeze. '96 Ford Taurus SHO Skunk - '17 Vodden (Hope for the Future award - not me, the rookies), '15 Pointless, Button Turrible.

Re: "Racing" the Duff Beer Electric Car

This was a real accomplishment.  Congratulations!

Be careful when you break into your new battery pack if you feel the need to repackage it.  Manufacturers get nervous when you crack into their packaging.  We had a couple of "pre-alpha prototype" (the vendor's description on the manual) high voltage NiMH batteries about 10 years ago, and we couldn't get support from the manufacturer, so we were replacing individual cells in one battery from the other in order to keep the project going.  When they discovered what we were doing, they rebuilt both batteries for cheap and asked us to please not do that any more.

A little inspiration.  White Zombie, a 10 sec, street legal Datsun 510.

Formula None
Because Saab Turbos have too much power
Inexplicably OC @ Humidi TT 2014

Re: "Racing" the Duff Beer Electric Car

It came out of a 2012 Chevy Volt. It is already broken up internally into 24v and 48v packs, so not much is required to build the 96v packs that we want. The 48v packs are already popular as golf cart battery upgrades. I don't plan on messing with the individual cells. I picked the Volt battery assembly because there are plenty of them at salvage yards, and the way that the Chevy BMS worked, they tend to be in good condition. I can also get them for less than $100/kWh, which is pretty cheap.

Next on the list is pulling the motor to verify the shaft type and housing bolt pattern so we can look at alternatives.

We also need a BMS and charger, controller, and probably other stuff.

Everybody grab your brooms, it's shenanigans!

Re: "Racing" the Duff Beer Electric Car


Re: "Racing" the Duff Beer Electric Car

Spank wrote:

Reading this, now I understand why there are water-cooled electric motors.

Actually, there are several oil cooled options. But a modern power system designed for high speed/torque applications that hasn't had 17 generations of squirrels living in it will be perfectly adequate. The only question right now is regenerative braking; that means an AC motor, which means higher volts and amps. (the AC50 is 4x what's in it now.) The WarP 9 DC motor can take 190A continuous (450 peak, 225 for 1hr) But a brushed DC motor has stalling concerns, brushes that wear, and brush dust causes ground isolation faults. (the current GE motor is leaking ~32v to the chassis) If I go DC, it'll likely be a 144v system to have mostly ICE torque/power curve; @72v it peaks about 3000rpm. We already drive it like an automatic leaving it in 3rd. A W9 will get us to 70mph in 3rd - just, 5200rpm puts us up at the 5500rpm design limit. (yes, there are idiots that spin 'em >10k in drag applications; they also throw 4000A into them. The armature is spun tested to 10k.) [I don't have that data for the HPEVS AC50]

Duff Beer Civic (#128) -- 2014 Sebring - Class B (#1 of 7), 2016 Barber - Class B
1981 Jet Electrica 007 [Plymouth Horizon TC3] (#128) -- Mk.1 - Index of Effluency Eco (IOEe) @ 2016 Lemons South Fall, Mk.2 - Judges' Choice @ 2017 'Shine Country Classic, Mk.3 - Index of Effluency @ 2017 Southern Discomfort

Re: "Racing" the Duff Beer Electric Car

Very nice.

Have you thought about sourcing a Zero Motorcycles power train?

The lithium ion packs are very compact, the 3 phase AC motor does regen and the sevcon controller is off the shelf.

It's all air cooled and makes decent power.

'96 Dodge Neon, a.k.a. "Neon Pope" - 20 Lemons races - 1 Class B win

Re: "Racing" the Duff Beer Electric Car

For motors, the car currently has a 9" industrial motor with a 1.125" shaft. There are enough modern units with the same form factor that should bolt right up that it doesn't make sense to me to try anything too different. We're going to have enough problems without making any new ones for ourselves.

After tearing down the Volt battery pack, I really like these batteries. The hold-down mechanism is going to make it much easier to secure than the Sam's Club batteries. I'm going to assemble them in to 144v, 6kWh packs, then probably put 3-5 of them in parallel in the car. They also sell for $100/kWh, which is as cheap as lead-acid batteries. I figure some quick-disconnect plugs and a couple of lockdown bars should keep it secure and maybe we'll even do a hot pit refuel.

Everybody grab your brooms, it's shenanigans!

Re: "Racing" the Duff Beer Electric Car

i was sitting with roger at the bbq, discussing the benefits of an a/c motor. The only difficulty I see is you having enough voltage to run an industrial VFD. They typically run around 330 vdc for a 240 volt motor and 660 for a 480.

I'm not familiar with the voltages/ controls in the new car motors/ controls.

You really don't need more hp, just need to take care of the overheating. Typically, an industrial VFD can put out up to 150% full load current, which is plenty of torque for acceleration.

Silent But Deadly Racing- Chief cook and bottle washer, Former Flyin Turd Race Team Captain 
Ricky Bobby's Laughing Clown Malt Liquor Thunderbird Turbo Coupe, Datsun 510, 87 Mustang (The Race Team Formerly Known as Prince), 72 Pinto Squire waggy, Parnelli Jones 67 Galaxie
Besmirching race tracks in the Eastern US since 2001

Re: "Racing" the Duff Beer Electric Car

More progress, here's one of the 48-volt battery packs. I'm currently working with arranging them in to different configurations and figuring out coolant and voltage routing:


Here are a couple of assembled 96v packs with some loose 24v and 48v packls behind them, although it looks like we'll be using them in 144v packs for the finished powertrain.


The old motor, bolted to a '74-'84 VW Rabbit transmission. Luckily Rabbits were popular EV conversion candidates back when that was a thing, so there are plenty of pre-engineered adapter kits to attach a modern motor to. Interestingly, the axles were attached by bolts that were completely loose and flopping around. I removed them with my fingers. I'll have to loc-tite those. Shortly after I took this picture, I dropped the motor out the bottom of it:


And finally, another Volt battery pack showed up today. Note the fancy custom dolly that I built for it. Getting the first one from the parking lot out front to the shop bay out back was not fun at all. I've got a Volt battery pack disassembly line set up here. I ordered a programmable hobbyist charger/discharger for RC car battery packs that will let me test and balance cells. I'm going to have no end of fun playing with these toys:


The AC or DC motor question is still in the air. I originally wanted DC because it's simpler/cheaper, but apparently AC motors are much better at heat dissipation because they don't build heat in the rotor like DC motors, so now I'm lobbying for an AC motor.

Note, as I'm typing this, the Simpsons is playing in the background and the electric car scene from Drdanteiii's post just played; creepy.

Everybody grab your brooms, it's shenanigans!

Re: "Racing" the Duff Beer Electric Car

Go AC and dont look back.

Re: "Racing" the Duff Beer Electric Car

That's going to be Ricky's decision. It is, after all, his car. I think he originally wanted AC and I wanted DC, but now we have reversed positions. My main concern is managing heat, and I think that AC has an advantage there.

Everybody grab your brooms, it's shenanigans!

24 (edited by Team Infinniti 2016-09-30 06:17 AM)

Re: "Racing" the Duff Beer Electric Car

Never had the time or $$ to get a proper pack together.


Homestead Chump 5th-Sebring 6th-PBIR Lemons 9th - Charlotte Chump  CrashnBurn 9th
Sebring 6th again -NOLA Chump 1st -PBIR Chump Trans Fail 16th
Daytona 11th - Sebring 6th - Atlanta Motor Speedway 2nd - Road Atlanta Trans Fail 61st-Road Atlanta 5th
Daytona 13th - Charlotte 9th - Sebring 2nd-Charlotte 25th broken brakes - Road Atlanta 14 10th-Daytona 14  58th- Humid TT 19th Judges' Choice!

Re: "Racing" the Duff Beer Electric Car


Five 144v battery packs. I figure three of these packs in parallel will be a tank of gas. I've got one more Volt assembly ordered, which should be here next week. I'll get a couple more 144v batteries out of that. I'm thinking that we'll have two sets of batteries for Barber and maybe 3-4 sets for the next CMP race. Before it's all over, I'd like to be able to drive it for an hour stint (45 minutes racing, three cool-down laps, and a pit stop) on a set of batteries and have enough batteries to last all day.

Ricky is getting us a big-ass AC motor and controller; the car should be pretty quick.

I'm working on cooling plumbing for the batteries and controller, as well as electrical connectivity. I've found some high volume medical quick-disconnects for the coolant lines, and 350A Anderson connectors for the batteries. Ideally I'd like to do a hot-pit refuel next race, not that it would gain us anything, but eventually I'd like to get enough performance and batteries for the car to turn 300+ laps.

Ricky is working on a charging system for it using big Cisco switch power supplies controlled by RC vehicle chargers. Craig from Terminally Confused is working on a battery cell balancing system. I'm working on a cell monitoring and alerting system. Lithium ion batteries are more complicated to manage correctly, but should be worth it.

I'll have to take a break from this car for a bit; I'm going to Romania for a few weeks for work and I've got to get the transmission in the Duff car fixed for our COTA race in December, but I'll post as we get stuff done.

Everybody grab your brooms, it's shenanigans!