KEN KOCH’S 1934 FORD ROADSTER PROJECT
Most Powerful EV Built to Date

Having sold KTA Services, the EV parts supply business, I now am able to achieve some semblance of retirement. This has created extra time whereby I can work on a personal project I’ve wanted to do for a very long time: To build up a 1934 Ford roadster street rod. Back in high school I used to race my car at a local drag strip every weekend, and this created a need for speed that’s still in my blood today. When I was a teenager, everyone dreamt of having an early 30’s street rod. I was no exception. Of course, at that time not many could afford to fulfill this dream. For anyone who eventually could afford it, it simply had to wait until years later. Well, now’s the time, before it’s too late! What could be nicer than a gorgeous-looking street rod which is ELECTRIC and possesses HUNDREDS of ponies under the hood?

INSPIRATION COMES NEXT

Any project conceived by the human mind requires inspiration to build it and sustain it. This roadster project may have been conceived in my teenage years, but the type of drive system employed didn’t come into focus until years later. Sure, I could have built up a 500+ hp Hemi and put it under the hood, but that’s been done many times before. After watching the EV industry grow to produce higher and higher-powered motors, controllers, and batteries, this project absolutely had to be powered by an all-electric drive system. However, all of this thinking didn’t come together without the influence and inspiration of others.

First and foremost I must thank my good racing buddy, Jim Ludiker, whom I partnered with to create the “Circuit Breaker” dragster. This race machine was a test bed for our ideas, crafted into hardware, and then tested under such extreme conditions that it would shock the average drag strip attendee if he/she only knew what we were up to. The “Circuit Breaker” saw its best 1/4-mile performance from 1999 through 2001: 136 mph in 9.44 seconds. That’s not bad for something full of lead! This machine was a converted top alcohol dragster (250”) that formerly contained a 2000 hp engine. We stuffed in a pair of stock 12” G.E. motors, ran a pair of 1800 amp Café Electric Godzilla controllers, and twin 336-volt JCI Inspira battery packs. The rest of the drive system consisted of a 2-speed racing power glide tranny and a heavy-duty Ford 9” rear end. The dragster was inspirational: 60 ft. time of 1.28 sec.; 1/8-mile at 5.82 sec/119 mph; 0-60 mph in 1.85 sec.

Nobody could talk about EV racing inspiration without mentioning Dennis Berube and his “Current Eliminator” dragster and “Smoke Screen” Chevy S10 pickup. Dennis has more 1/4-mile time slips than all the rest of EV drag racing combined. Some of his time slips are sub 8-seconds, with his best “Current Eliminator” effort in December 2007 at 7.956 sec./160 mph. Equally impressive are Bill Dube’s A123 Killa-cycle numbers: 7.890 sec./174 mph in October 2008. The National Electric Drag Racing Association (NEDRA) world is hoping that these two racers will duke it out on the track someday. But bottom line, Dennis is the consummate EV racer. In the not to distant future drag racing could see its first 6-sec./200 mph pass in an electric. Dennis is the person most likely to make this happen.

Three years ago Tom Conley brought his ’28 Ford EV roadster (with ’32 grille) to my shop and asked me to work on it. The wiring needed some help. Tom is about my age, and this lucky guy’s been building roadsters most of his adult life – about 18 in all. This roadster may be work in progress, but what fun and inspiration it was to have it around for a brief while. The car truly is a street rod, even though it was never intended to burn up the streets. It has a 48-volt battery pack with a 5 hp motor and controller from a lift truck. Top speed is only 33 mph, but the roadster does everything Tom intended for it. It’s well known around the streets of Lake Havasu, providing him with one of the neatest rides in town. Tom has provided much-needed mentoring to give my street rod the right roadster equipment and just the right look.

EARLY PROJECT DECISIONS

No project can be completed until its inclination, time, and money all coincide at the same time. No problem with the inclination part. Once the budget was established, creating enough time was the next challenge. Things gradually got under way in late 2005. First, I needed to decide whether I truly should be building a street roadster that can be licensed and insured to drive on public roads, or should it be a dedicated racecar that could be driven only on the drag strip? After all, the car’s drive system I had in mind could produce up to 800 hp. However, full-out performance with 800 peak hp, lithium ion batteries, and 2600 lbs., in theory, calculates out to a very scary 157 mph at about 8.7 seconds in the 1/4-mile. Being enamored with these numbers for a brief while, I had to ask myself if this was what I really wanted to accomplish. It would require building a custom race vehicle with a chrome-moly tube chassis, full roll cage, and all the other equipment that the NHRA requires for this kind of performance. It would be impossible to drive it on the street. After a while I finally came to my senses and decided that the roadster would be one my wife and I could enjoy driving on the street, plus take to car shows, parades, and hot rod cruises. Trips to the drag strip to check its performance and race against others then became only secondary in purpose. There was no reason to produce 800 peak hp to accomplish what we wanted the roadster to do – but – 600 would be adequate! Hmmmm, let’s see: 600 peak hp, lithium ions, and 2600 lbs. calculates out to a more reasonable 142 mph and 9.4 seconds in the 1/4. Now that’s a bit more sane.

The most popular early Ford being restored or built today is the 1932. The “Deuce,” as it’s called, is very recognizable with its bull nose grille. My initial preference was to build up a ’32, but then I discovered that it wouldn’t have enough room under the hood for the two-motor drive system I wanted to use. I also learned that a ’32 isn’t too spacious when it comes to legroom, so I opted to go with a ’34 instead. There’s ample room to mount two big motors in tandem configuration, which is a must. The ’34 also has more legroom and a slightly longer wheelbase compared to the ’32. Since the ’34 was a close second choice in personal preference, I decided that I’d go with the ’34. Its grille (as shown on the left) is probably the most distinctive of all the early Fords.

ELECTRICAL DRIVE MOTORS

The “Circuit Breaker” dragster was retired and parted out in late 2005. I purchased the two motors, ATO power glide transmission, and some of the electronics before the rest of it wound up in Australia via E-bay. This purchase seemed the right thing to do if I were going to give my roadster a good foundation for high performance. (Besides that, I didn’t want the two 300 peak hp motors to wind up in someone else’s hands, and my having to race against them someday.) After conferring with Dennis Berube, I was convinced that he could perform some of his special magic to make them 400 peak hp each. Dennis took on the task, but it was a daunting one that consumed months of meticulous work in his spare time. I had to promise that I wouldn’t put these two monsters in a dragster and race them against him.

At last the motors are completed, tested, and are ready for installation. The motor bodies are industrial hard chrome plated with powder-coated ends to match the chrome and metallic candy tangerine color theme of the roadster. Shown in the photo to the right, they look absolutely terrific! I’ve decided to dub them the “Diabolical Duo” by Dennis. (Also shown is the monster 13” G.E. motor Dennis built up to go into his new Chevy S10 “Smoke Screen” race truck.) The “Diabolical Duo,” when chain-coupled end-to-end, represent the most
powerful pair of EV motors in captivity. Here are some of the specs for each motor:

• Series-wound DC, 4-pole, w/interpole windings
• 12” diameter, 230 lbs.
• 400 peak horsepower
• 8000 rpm maximum
• 400 volts DC maximum
• 2000 amps DC maximum
• 775 ft.-lbs. peak torque

ELECTRONIC MOTOR CONTROLLERS

Of course, the roadster had to have the best, most powerful motor controllers available. They also needed to be computer-programmable. There is some lead-time to endure, but they are an absolute must if you’re gonna go racing. These are the Zilla Z2K-EHVs made by Café Electric.

I had two of them built, along with their “Hairball” logic control boxes, and after 6 months they were delivered exactly as I wanted them with metallic candy tangerine cases. One will be applied to each motor, and each will have its own 370-volt battery pack. Individual specs are as follows: 36-400 volts DC max voltage range 2000 amps DC maximum 15.7 kHz switching frequency 640 kW peak power Programmable battery voltage & current limits Programmable motor voltage & current limits Liquid cooled 37 lbs.

ELECTRICAL INSTRUMENTATION

Once the battery pack maximum voltage and current, maximum motor current, plus rpm range were established, it then became possible to define the instrumentation. And since there would be two battery packs, two motors, and two controllers, it was a natural decision to monitor all of those things with some pretty nice–looking gauges. Everything would have to be custom made, and the folks who do that best are Westberg Manufacturing. The analog speedometer/odometer and tachometer are 3.75” diameter, and are programmable with magnetic pickup drivers. The ammeters and voltmeters also are analog, voltage driven, and 3.00” diameter. Individual specs are as follows:

• Tachometer is 0-8000 rpm, pulse-driven
• Speedometer is 0-120 mph, LCD odometer readout
• Both ammeters are 0-1500 amps, 50 mVFS
• Both voltmeters are 200-400 vdc
• 12-volt illumination on all gauges

THE WHEELS PRECEDE

Having never built a street rod from scratch, I thought that I could simply order a fiberglass ’34 body, have a frame and chassis manufacturer put together one of their ’34 packages, and then slap on a trick set of wheels. Little did I know that it all starts with the wheels. The chassis totally depends on tire size and wheel backspacing. The body to a large extent does too, because clearances need to conform to wheel diameters and widths. I also knew that I wanted lots of stopping power, so 13” diameter brakes were preferred. This meant that the wheels had to be at least 17” to accommodate the brakes. Another requirement was to have the right look with skinny tires up front, and fat tires in the rear, all with matching tread pattern. I poured through tons of wheel and tire brochures, and finally settled on Mickey Thompson (M/T) tires and wheels. For the front I ordered M/T Sportsman S/R radials in a #26X6.00R18LT size with HR-2 #15X4.5 wheels. For the rear I ordered M/T S/Rs in a #29X18.00R18LT size with HR-2 #18X15.5 wheels. The wheels are forged and polished aluminum. You’ll have to admit that I’ve achieved the “fat (17.2” wide) vs. skinny (6.3” wide) look, but I know that the drive motors put out a lot of torque, so the car would need serious rear “meats” to hook up all that power to the tarmac.

FRAME, CHASSIS, AND SUSPENSION

Next, I looked around to see who might have a ’34 Ford chassis available that could handle the power of the drive system and stop the vehicle quickly (just in case I might drive it fast someday). After researching I concluded that Total Cost Involved Engineering (TCI) had the best package with the most options. I chose their complete ’34 Pro-Street setup. It seemed the right decision because going this route would save a lot of time compared to building much of it from scratch. The frame is very strong and rigid, and is intended for “some of the wildest, baddest street rods built.” I found TCI to be quite knowledgeable based on their years of experience, and also very easy to work with when it came to defining the right options. One thing that really needed definition was what type of rear end could handle up to 3500 ft.-lbs of input torque, and, be selectable as either a differential or a spool. A differential for street driving was a must, as you can imagine the scrubbing and squalling noise a set of 17.2” wide tires would make around a turn if the rear end were locked up. The other side of the coin was that I needed a locked rear end for racing if I hoped to aim the car in a straight line. TCI’s solution was to use a Dana 60 “E-Locker.” Pretty simple: It’s normally a differential; send it 12-volts and it locks up electromechanically.

Now that the ’34 Pro-Street chassis, frame, and suspension are completed, I must say that the entire package is everything I had hoped for. The frame is a piece of artwork and the weld joints are a thing of beauty. The 4-link suspension is set up to handle lots of torque. The stopping power should be good. Here are some of the items that went into its construction: Custom independent front suspension Polished 13” front and rear drilled triple brake rotors Polished 6-piston brake calipers Stainless steel brake lines Chrome-moly 4-link suspension Dana 60 E-locker rear end, 4.11:1 gears Currie 35-spline forged alloy axles Billet yoke and pinion support Severe C-notch to accommodate rear wheels Billet adjustable rear coil-over shocks Master cylinder and 7” dual diaphragm brake booster Rear anti-sway bar Proportional valve, stop light switch, and line lock X-member central brace and drive shaft loop Rack and pinion steering

THE BODY, FENDERS, AND RUNNING BOARDS

There are lots of companies who manufacture early Ford bodies in fiberglass and steel, but a very small number who make them in aluminum and carbon fiber. The latter two were out of the question, in spite of their light weight and strength, because the price tag was just too high. Wescott’s Auto Restyling specializes in fiberglass. After checking around they seemed to have the best reputation for quality, fit, and completeness. We decided to check them out personally. In August, 2007, Wanda and I took a trip to Oregon which included a Wescott’s factory tour. They were courteous, helpful, and left us with the opinion that they are experts in their craft. The steel braces they employ in specific areas around the body add strength and rigidity. Initially I was concerned that the fiberglass pieces might be excessively heavy at about 600 lbs., but Wescott’s allayed my fears with a more respectable estimate of 400-450 lbs.
They also took extra time to answer all of my questions. In February, 2008, we ordered the ’34 roadster body and all of the pieces. They were delivered in June.

PUTTING IT ALL TOGETHER WITH A BUILDER

While the chassis and body were being readied, I looked around in earnest for a shop that could put everything together – everything except the electrical and electronics. Having a builder far distant from my address didn’t make sense. Who wants to hop on an airplane every time you need to answer questions, give direction, or make critical decisions? So I looked within a 30-mile radius and found several hot rod builders who had experience putting together street rods with fiberglass bodies. Some were too busy and couldn’t take on the project for months. Still others wanted you to ransom one of your kids for a down payment. But by sheer coincidence I received three referrals to one builder all within the same week. I picked up his business card at a powder coating shop, another at a street rod show, and the third from my neighbor who has a beautiful ’34 Ford roadster rebuilt by Brian Noppert of Ultimate Customs. Brian’s shop is in Ontario, California, only 8 miles from my house. All of this coincidence had to mean something, so I gave him a call. “Hey Brian, we’ve never met before, but I feel as though I know you. Your reputation and your work precede you, and I’ve got a project that I think you’ll find unique and interesting.” The conversation went well from there, and so we cemented the deal. Brian is a multitalented young man whose portfolio of custom vehicles grows with each passing day. A recent build of his is a ’50 Ford with a blown Lincoln Navigator engine, featured in the September 2007 issue of Hot Rod Magazine. I feel very confident with my pet project placed in Brian’s hands.

To date, Ultimate Customs has accomplished about 85% of the work required. They have designed and installed an adapter and motor mounts to put the transmission and two motors in place. The motors are securely mounted to the frame, and are joined together in the middle with a heavy-duty chain coupler. Boy, what a job the motor installation was! Ordering the roadster body with a 6-inch recessed firewall (for a big block engine) was a good idea. Can you imagine installing 39 inches of motor length under the hood of any vehicle, much less in a ’34 Ford? Nevertheless, the two motors and the transmission have been engineered into place with perfect alignment to the differential.

All the body pieces have been installed, joined to the frame and each other, and then tweaked for best fit and appearance. This includes the running boards, fenders, grille, trunk lid, dashboard, hood top, and hood side panels. Also in place are the two low-profile seats, windshield, headlights, taillights, steering column and wheel, foot brake, accelerator pedal, emergency brake and cables, remotely operated trunk latch, and drive shaft. Just behind the grille a special shroud has been fabricated and installed. This shroud closes off the grille except for two 400 cfm fans, each of which can be used to force air into the motors and across a small transmission cooler to provide cooling for the two Zilla controllers. Also installed is a vertical 3/16” plate that will be used to mount up all the power electronics.

The last 15% of Ultimate Customs’ work will be to mount the battery boxes securely to the frame, build a bulkhead between the trunk and passenger compartment, and finally to design and install a six-point roll bar. After that it’s teardown the car and sort all the parts into four piles: Paint, powder coat, chrome plate, or metal polish. More later as work progresses….

THE BATTERIES, LOTS OF BATTERIES

It took a long time to finally resolve this portion of the roadster project. I knew early on that I needed a set of batteries which would be nearly equal to the 800 hp that could be produced by the motors. I also knew that the batteries might be multiple smaller cells such as A123’s #26650 M1 lithium-iron-phosphate. Even though the project was well underway without a battery solution in hand, I was afraid that I might have to remove the floorboard and do the Fred Flintstone thing if no solution presented itself. Finally, I was contacted by the guys at Go Wheel Group, and they referred me to ev-battery.com. They have been manufacturing 13.2 volt modules which contain 24 of the #26650's in a 4-series, 6-parallel (4S6P) arrangement. ev-battery.com has been selling their 13.2 volt modules which contain 24 of the #26650’s in a 4-series, 6-parallel (4S6P) arrangement.

After taking a close look at what ev-battery.com had to offer, I decided that this approach made good sense. I knew I needed around 360 volts and 1200+ amps from each of the two battery packs. A total of 2592 cells could produce this kind of power, but the wiring, interconnection, and battery management (BMS) would be hugely complex. Instead, the same thing could be accomplished by using 108 of the 13.2 volt modules that already contained the BMS. Interwiring would be much simpler….simply interconnect the main terminals using 3/4 X 3/16 inch solid copper bus bars. So, basically, the plan is to have two battery packs each comprised of two parallel strings of 27 modules. 54 modules per pack, 108 modules total. Each pack’s rating is 356.4 volts nominal with an output current of 1440 amps maximum for 10 seconds. This would be great for the drag strip, but would still allow the roadster to have reasonable range, estimated at 75 to 125 miles-per-charge.

I recognized right away that it would be helpful to design and build a battery tester, as it would be necessary to check all 108 battery modules from time-to-time for power delivery and consistency. Of course, the most accurate way to test batteries would be to charge them consistently, and then discharge them consistently at a preset current level. Since the voltage of any loaded battery varies with time, the load must remain constant. A simple load resistor requires continual adjustment to keep the current constant, and that’s way too time-consuming. I used two 400 amp motor controllers and two high power resistor banks. Total current is held constant according to potentiometer input, and is presettable from 0 to 800 amps. Input range is 8.5 to 24 volts. The load shuts off automatically according to dialed preset voltage. An elapsed time meter records load time to within 1/10th of a second.

Testing a battery now is pretty simple. Dial in the shutoff voltage and test current, zero the elapsed time meter, then push the start button. When it’s done it shuts off. Simply record the elapsed time and move on to the next battery. The tester is only a breadboard for now, but it’s usable on any battery of 12 to 24 volts. It’s also expandable in 400 amp increments. While the tester is heavy and somewhat cumbersome, I can roll it to a battery pack and connect it to individual batteries. Someday I may package it up into a metal console with cooling fans.

Packaging all 108 battery modules into the trunk of this ’34 Ford was challenging. In the first place, space was limited because the wheel wells are tubbed into the trunk 12 inches on each side to accommodate the super wide tires. There was only so much room to work with. Each battery module measures 6.75” H. x 5.2” W. x 3.38” D. and weighs 5.65 lbs. Trying to package them all in one layer wouldn’t work, so it became obvious that multiple layers would be required. It was decided to place the batteries into two individual aluminum boxes that could be lifted into or out of the trunk with a hoist. The boxes are being placed into a mounting tray which is attached to the frame. Each pack, including the box, will weigh in at about 320 lbs.

The batteries currently are on order. ev-battery.com has agreed to configure the BMS for each of the 108 batteries to drive an LED indicator. 54 LED indicators will be mounted on the sloping panel of each box, and will give blink codes showing the status of individual batteries. Codes will signal battery overvoltage, undervoltage, and overtemperature. A high current 500 volt DC fuse will be mounted in each box. Also, each battery is to have vent holes which will allow forced air cooling for extreme operation such as when drag racing. A thin plenum will draft air through holes in the end of each box that match up to the vent holes in the batteries. The packs will have two-pin aircraft type high current disconnects on their sides which will wire to the drive system.

I expect the batteries to be delivered in early December. It is also expected that the reassembled and freshly-painted car will be delivered around Christmas time. After that, it will take me a couple of months to install and complete all the electrical and power electronics. Upholstery will come after that. More later as work progresses….

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