mod@tech

[Editor’s Note: Some engine swaps are simple bolt-in affairs, while others require complete re-engineering of the vehicle. Swapping an air-cooled three-cylinder motorcycle engine for the air-cooled three-cylinder motorcycle engine already in his Berkeley should have fallen under the former category, but ended up more like the latter, as James Bornhorst details in this story he sent along.]

In 1968, I was at Texas A&M University, working part time at the Hydrodynamics Lab doing instrumentation for grad students working on thesis projects. My best friend at the time was Jeff Kirby, an electronics tech and 1st Lieutenant in the National Guard who had helped me avoid Viet Nam. Jeff worked in the Wildlife Management Department and built radio tracking collars for animals, all kind of animals; deer, turkey, bobcats, and even snakes. He was a sports car enthusiast who owned an old Volvo P1800S and a beautiful white Jaguar E-Type. We were such fast friends that my wife was jealous at times. I would ride late nights on weekends to South Texas with Jeff in that Jag, at breathtaking speeds, to deliver tracking collars and test them at wildlife refuges. He liked to drive with his right shoe off so he could curl his toes over the top of the big aluminum throttle pedal and better feel the machine.

At A&M we would attend local gymkhanas together and were constantly impressed by a little yellow car owned by a local bachelor photographer, Roland Chatham. He would always beat the socks off of the other competitors. We learned the car was a rare and unique British fiberglass job known by its British pronunciation “Ba-kli”, Americanized to “Bark-ley.” It came to pass that Roland was getting old and wanted to sell the Berkeley so Jeff bought it, for $300 as I recall. It was so unique with its two-stroke air cooled three-cylinder motorcycle engine and front-wheel chain-drive (unheard of in 1968), incredibly small, and fetchingly cute. Oh, and it was fast as hell! We were both completely smitten. Not long after, Jeff was moving on for a new job and needed to sell the car. I couldn’t pass it up. I paid him $250 and drove the car home to our rental duplex where it tucked neatly in the gravel-bedded carport next to our “real car,” a Volkswagen SquareBack.

Photo courtesy James Bornhorst

Eventually, I discovered that this was a rare production model of which very few, if any other at all, still exist. Records show that between October 1957 and March 1959, Berkeley Sports S-E 492 chassis numbering from 1 to 666 were produced in Biggleswade. Of those cars with chassis numbers up to 120, which was produced in April 1958, all had backward slanting door front edges with external hinges and no external door latch. The slant allowed the door to swing slightly upward when opened allowing for easier access. My Berk was chassis number 40, so it is either a late 1957 model or an early 1958. Berkeley could have easily produced 40 cars in the last three months of 1957 so I call mine a ’57. But I have no proof.

The car’s shortcomings soon became apparent. It smoked like a chimney due to the 6:1 gas/oil mixture required by the Excelsior engine. The plugs fouled all the time and there was always an oily smell and mess associated with the car – and, as a result, me. It ran hot and inefficient because its center cylinder never properly cooled. Turns out that Excelsior had taken a relatively good 328cc twin, cut it half, and added the middle jug to boost displacement to 498cc. Unfortunately that cylinder had much less fin area for cooling, plus it was irradiated by the adjacent two!

The biggest problem with it, though, like so many British cars of that era, was the ignition system. The two-stroke high-revving three-cylinder engine required three hot sparks every revolution. At 5,000 RPM, the spark frequency was 250 Hz (4 milliseconds/spark), far too fast for a Lucas coil to recharge and deliver at the time. The Excelsior solution was to pack three independent sets of points with three individual condensers around a cam shaped extension of the crankshaft. Each set of points fired its own individual spark coil which connected to its plug. No distributor necessary. The points assembly occupied an inaccessible spot on the lower passenger side end of the engine accessible only through the wheel well with the tire dismounted. And the points constantly needed adjustment because the phenolic cam followers wore at an alarming rate on the hot crankshaft. To time the engine, the screws holding the single plate mounting all the points had to be loosened and the plate rotated with the No. 2 piston at 11/64” BTDC. A nearly impossible task.

The first improvement I undertook was to design a new ignition system for the engine. New high-voltage power transistors were becoming available as were CD (capacitive discharge) ignition systems. In my spare time, I designed a replacement assembly for the points employing photo diodes and a rotating light shutter to trigger the spark timing. The trigger worked pretty well but the downfall was the CD system needed to jolt the spark coils. Partially due to my lack of design skill and partially due to the state of HV transistors at the time, the CD system never worked.

The Berkeley sans hood on a road trip in 1969.Photo courtesy James Bornhorst

Other problems were to be lived with at the time. I began to use marine two-stroke oil to reduce smoking and ran with the bonnet off in the summer for improved cooling. The leaky rag top and side curtains and lack of any defrost or heater, other than a hole cut through the fire wall, dictated it stay garaged during inclement weather. Not a big sacrifice in Texas, but what did the British do?

On a National Guard weekend drill I was telling stories of the car to some of the other ground pounders and complaining of the problems I was having. One of the guys recommended I just replace the whole engine. He happened to have recently acquired a Kawasaki H1 MACH III 500cc street bike, which was designed by Kawasaki to compete with Honda’s new 750cc transverse four-cylinder four-stroke street bike and would do a quarter mile in 13 seconds. The H1, with its three-cylinder two-stroke half-liter air-cooled engine, should have been a perfect replacement for the Berkeley’s Excelsior. The big plusses were its unique (at the time) oil injection system and a CD ignition system! So no smoke and no fiddling with points. And by the way, the H1 produced 60 horsepower, twice the Excelsior’s 30, with just half of the mass of the old iron Excelsior engine. And it had a five-speed transmission.

The Kawasaki with the BerkeleyPhoto courtesy James Bornhorst

So the guy said he would sell the bike to me cheap. The problem was that the bike was stolen. Well, I thought, no matter. If I stripped the engine out and dumped the bike frame no one could possibly trace it, right? The Berkeley would take on a new life! So we did the deal.

The Kawasaki was an almost perfect fit. I couldn’t believe that even the final drive sprocket lined up perfectly with the Berkeley’s sprocketed rotating differential. The old drive chain was a #40 and was always breaking, but the Kawasaki had a #50 roller chain at about double the strength. I could easily make a new #50 sprocket from a blank on the lathes at the Hydro Lab.

The Kawasaki engine in the Berkeley chassis today. Note the strengthened aluminum substructure.Photo courtesy Geoff Hacker

The rest of the Berkeley’s front-wheel-drive scheme consisted of two telescoping Spicer half shafts driving the front wheels. Each shaft had a simple U-joint at each end. The U-joints and telescoping mechanisms of the drive shafts allowed for suspension movement of the twin A-arms on both sides as well as left-to-right steering motion. The clever differential was bearing-mounted in a fixed cradle with a limited rocking motion allowing for chain tensioning. Simple but effective.

The only complicating issue was (and still is) what to do about an exhaust system. The Berkeley exhaust had a cylindrical collector connected to the cylinder ports that dumped gasses and unburned oil from the end of a small output pipe extending through the engine compartment floor. This was a poor solution because a two-stroke greatly benefits from a tuned exhaust and the massive collector blocked cooling air at the front of the engine. Furthermore, the hot collector itself compounded engine cooling issues. I decided I had to use the Kawasaki individual expansion chambers that came off the bike, but where to put them?

Undeterred and excited to experience the performance boost, I ripped the old Excelsior Talisman triple out of the car and began to fit the Japanese power plant. Other issues needed consideration, though. The Excelsior engine was equipped with a dual-purpose electric generator/starter motor uniquely incapable at both tasks. The generator function was unable to provide enough juice to keep the battery charged if the headlights were on and the starter drained the battery in a flash as you tried to start the car with fouled plugs. On the other hand, the Kawasaki had a great alternator that kept the tiny, by comparison, motorcycle battery topped up under all condition. But the engine had no self-starter. The other issue, motorcycles had no reverse gear back then. Initially, I solved these issues by opening the bonnet and sticking a foot in the engine compartment to kick-start the engine. The reversing issue was solved by just lifting the car from the rear. Parallel parking was a snap.

Kyle Feller demonstrates the Berkeley’s reversing technique.Photo courtesy Geoff Hacker

So the H1 engine was in and mounted to the sheetmetal bottom pan of the Berkeley’s engine compartment. Ignition components were hung on the compartment bulkheads as was the engine oil injector tank. A gear shift was rigged using the Berkeley shifter components through the firewall; one-down, four-up didn’t exactly match the four-inline pattern of the Excelsior, but the shifter worked snappily. The stock Kawasaki clutch cable worked just like the Excelsior’s, as did the throttle cables. They were of course, both motorcycle engines. Fuel lines and electrical support, no problems. It was almost ready to go. Still, what to do about exhaust? The two-stroke would not run right without proper back pressure timing. I finally decided to simply hang the bike’s expansion chambers under the front end of the car, sacrificing the little bit of ground clearance the vehicle had to begin with. The Kawasaki’s curved exhaust tubes exited through the front grill, which worked well with my under mount exhaust scheme and all was well, for the time being.

The first time I started the car with the new engine, it fired right up. The energy of the new power plant was also unmistakable. I eased out of the driveway going forward and immediately dragged the mufflers. Undaunted, I hit the streets and had a thrilling ride, better than I had imagined. The H1 was incredibly responsive and breathtakingly quick when it reached about 4,000 RPM. It literally smoked the tires in second gear. Yahoo! I remember driving it around for a few months, taking care not to bottom out on railroad tracks and the like. It was fun to pull up to a muscle car at a stop light and smoke the front wheels on take off. The exhaust had a wonderful throaty sound that seemed way bigger than the car. But there was a downside.

The Berkeley front end was entirely constructed of .040” aluminum sheetmetal bonded into the fiberglass monocoque body. Remember, Berkeley was a caravan (travel trailer) manufacturer in the first place, so axle weight was critically important. The engine pan was very flexible and the H1 moved around a lot as it produced torque. The front suspension components were literally hung off of the aluminum side bulkheads, which were also very flexible. The suspension A-arms seemed remarkably wispy now. It became immediately apparent that the car needed some significant reinforcement if it were to be truly functional.

My wife’s family lived in Waco and had rental property there. I needed a proper place to work on the car as our exposed gravel-floored carport in Bryan was a miserable place to work. So I drove the car north, pulled into a proper garage my father-in-law graciously provided and began again. My mission was to completely rebuild the front end structure and refit the engine. I had also begun serious research into the design of expansion chambers for two-stroke engines. Then, another distraction. I became aware of a wrecked Berkeley Sport SE 328 that had hit a tree (driver survived, I was told). The owner was willing to give me the car, so what could I say?

Both Berkeleys on the trailerPhoto courtesy James Bornhorst

On our many weekends visiting Waco family, I spent most of my time at that garage working on the two cars. The first task was to remanufacture the front A-arms and their hangers, which I accomplished between weekday study halls in the A&M Hydro Lab shops using their machining tools and welding equipment. Progress was slow and eventually stopped. But my vision remained and was determined to drive that car again. I just needed a better environment to work and needed time. Hopefully graduation and a new job would yield both. Well, it didn’t. I couldn’t find a job as Viet Nam was winding down as the defense industry was shutting down. My wife and I eventually moved to Dallas with the two cars where I could conduct face-to-face job interviews.

Over the next several years, I managed to do some work on the yellow car in slow times, fabricating an aluminum engine cradle and forming front end structures from square structural aluminum tubing in Showco’s shop. The black car moldered. I gave it away to a workmate in 1985 and have no idea what happened to it after that.

The yellow car moved with us from house to house, always under cover with the dream of restoration not far out of mind. The project eventually became slated for retirement years, which came way too soon. At 77 years of age, two things became painfully apparent. One, I was not skilled enough and didn’t have the proper tools to do what rightly needed to be done. Two, I was getting old, and I was never going to finish the car. It was time to find that Berk a new home with someone who would appreciate the forward thinking that came out of Berkeley Coachworks’ design studio in Biggleswade in the mid-1950s.

I would have been satisfied if the car was just cleaned up and added to someone’s collection of dusty hanger queens. But in late November, I was introduced to Kyle Feller, a young and gifted restorer with a focus on small and unusual cars. Perfect!

Kyle now has the car at his St. Louis area shop and has begun work on it. He has committed to restoring not only the Berk, but also the old Kawasaki engine. The H1 was put up years ago with care so hopefully it is salvageable. And speaking of commitments, Kyle is shooting for a first showing in September of this year. He says he will film me driving the Berk again!

This is why I kept that lovely little car all those years.

Who doesn’t love finding an old former racing machine that still has some life inside? Enthusiast Matt Kurek of Mullica Hill, New Jersey was lucky enough to grab a 1972 Plymouth Duster that once lived its life a quarter-mile at a time. “I got a tip from a friend of mine that this car was sitting in a backyard near my house. I figured I’d head out and take a look. I’m happy I did,” states Matt.

Though the car’s racer origins are most prominent, the Duster was born with a solid pedigree. Originally this A-body was a 340/4-speed car with a 3.91 Sure Grip-equipped rear axle. The B3 Basin Street Blue paint is the original paint for the car..

Kurek made the short trip over to the yard in question to find this forlorn Plymouth sitting in the high grass. From the looks of things, the Duster had been there for quite a while. “I took a quick look at it. For what this car had probably gone through over the years, it was still in reasonably good, restorable shape. I mean, it needed work, but it wasn’t a basket case. The paint really grabbed my eye and as you could tell, it had been a racer for at least part of its life.”

The “shark tooth” grille was available for 1971 and 1972 Dusters and is a coveted item. The J54 scoop was a 1971-’72 Dodge Demon item, though finding one on a Duster is pretty common. Note the tow tabs on the front bumper…before everyone had a truck and trailer, the race car was flat-towed!

A quick look-over said that even without the drag racing history, this Duster was something to have. The twin snorkel scoop, an option on the 1971-’72 Dodge Demon, is commonly installed on A-body Mopars to give them a proper muscle car look that separates them from their pedestrian Dart/Valiant origins. Of course, that shark-tooth grille up front, a 1971-’72 option, is something every A-body fanatic wants on their ride. The Duster’s grille appeared to have a dose of body color added to it along the way. However, there was one more modification that really stuck out when Matt checked over the car.

The craziest modification were these light-up “440” callouts on the rear quarter panels. After cutting out the numbers, the previous owner created a light box behind Plexiglas. Hit the switch, light up the numbers, and show everybody what they were up against.

That one customization was the “light up” 440 call-outs on the rear quarters. “This guy went out of his way to let everyone know what he had under the hood. He devised a neat system in the trunk to “light up” his engine call outs.” On the rear haunches of the Duster, the previous owner built lighting fixtures to illuminate the “440” numbers, which he cut out of each quarter panel. Then Plexiglas was mounted in the numbers to finish off the look the owner wanted.

The engine bay of the Duster tells the tale: fender well headers and an engine plate meant for a 440ci big-block application.

Under the hood, there were also remnants of days gone past. “Someone cut out the inner fenders for a set of fenderwell headers, which are still present. The car also had custom-made aluminum engine plates installed to mount the big 440. There is a fuel cooler can still attached to the radiator support up front,” Kurik told us. A set of rusty tow tabs on the bumper and a set of crusty Cragar Super Tricks at the corners give blatant clues to this car’s past drag race history.

A mainstay on drag racing machines in the 1970s, Cragar Super Tricks were some of the lightest wheels you could put on your ride. Don’t confuse them with the SS/T (Street Super Trick) that were DOT-legal…these aluminum classics aren’t.

Matt got some info on the history of the car when he purchased it. “The Duster is an original B3 Basin Street Blue ’72 four-speed 340-motivated ride, built up nice from the factory with a Sure Grip and 3.91 gears. Somewhere down the line, the owner wanted to do some serious drag racing, so the 440 was installed and was backed up by a 727 Torqueflite. It also has subframe connectors and a trunk mounted battery.”

The interior of the Duster was left mostly stock, minus the auxiliary panel for ignition, the fuel pump switches and the fuel pressure gauge, and the line-lock button laying on the carpet. The wide center hump and third pedal are from the car’s stock form as a 340/4-speed junior supercar.

The interior looks pretty much the way it was born, except for the hole made for the automatic shifter that was installed over the years, and an aluminum panel which houses the ignition and fuel pump switches and a gauge to keep track of fuel pressure. The buckets are still there, and the dash isn’t chewed up too bad.

After the powertrain was swapped into another car, the Duster was parked for about thirty years before Matt Kurek was able to purchase the car.

The car was raced at Old Bridge Township Raceway Park in Englishtown, New Jersey and was a street brawler as well for many years. At some point the powertrain was extracted and installed in a Plymouth Road Runner. The Duster was then parked behind the owner’s house for storage. After about thirty years of sitting, Matt made the move to make it his own. Maybe one day, this Duster will make its way back to the street, and who knows, it might have a few good runs left in it!