AN: Standard disclaimer... I don't own Kim Possible, the idea for the Roth Motor Company, A.J. Foyt, the Roth SL Coupe or the 'Sloth' nickname.
Classic Car File - 1962 Roth Motor Company SL 'Sloth' Coupe
Taken from pages 50-54 of Motorist Magazine, May 2007 issue, illustrations removed.
Built by the Roth Motor Company for only 4 months in 1962 before a government investigation and voluntary recall forced a complete redesign, the SL Coupe is one of the most interesting stories in American motoring history.
Born in the outskirts of Indianapolis, Indiana in 1925 the Roth Motor Company specialized in building sturdy, powerful and dependable family cars for an economical price. During the Depression this philosophy insured their survival while so many other manufacturers floundered. World War II saw Roth Firebrand Sedans used as the preferred staff transport for Generals Bradley, Montgomery and Patton due to the rugged dependability and speed of the model.
Postwar Roth continued with the same philosophy that had carried it through the lean years but as the 1950's came to a close found itself being eclipsed by the stylish new creations from it's American rivals in Detroit. Too small to face this adversary head on Roth was a company looking for a niche and inspiration came from overseas.
The mid 1960's saw an influx of sporty European coupes to the American market. Manufacturers like Sunbeam, Jaguar and Aston Martin were shipping powerful front engine, rear drive sports cars that had no US equivalent.
Management of the Roth company seized on this opportunity and commissioned their engineers and designers to create a car to exceed those of the 'foreign invaders'.
The designers came up with a classic coupe design, long nose, short rear deck, a style the Aston Martin DB5 would echo the following year. Engineering was then challenged to fit a chassis and drivetrain under this design and keep the weight low enough to have the same feel of the European competition while delivering American sized performance from the drivetrain.
The response to the challenges put forth by designers and more importantly the accountants would lead to major issues with what was dubbed the Roth SL Coupe.
But that was in the future, in late 1961 as excitement started to build for the radical new entry from the usually laid back Roth Company crowds would gather at dealerships at just the hint that a Roth SL Coupe had hit town. The local wealthy and elite that had looked down upon the sturdy, powerful and frugal Firebrand and Arrowhead sedans now appeared in showrooms placing orders for the Coupe. Production began just after Valentines Day 1962 with the first car being delivered soon after to the Mayor of Middleton Colorado as a gift for his new wife.
As more and more of the orders were filled the complaints began, usually within moments as the customers got up to speed and realized the car was showing a very high revolutions per minute amount and therefore a very loud engine sound signature for the low speed of 50 miles per hour. The initial wave of good press and cheery promises of fixes from the dealerships headed off most concerns, and cash payouts were rumored to have taken care of the rest. Dealers in the Roth network began to question the car which was supposed to be their savior, they knew the promises of fixes were just words. Rumors had already come from corporate via second hand. The car was all it would ever be, no more money would be spent.
Things seemed to go well for the first few months, complaints continued about the transmissions but overall the feeling about the car was good, the interior was well appointed and used good looking but not expensive materials. The sleek looks were seen as refreshing amongst the usual sedans produced by the other US automakers.
At precisely 12:00pm on May 16th, 1962 Mrs. Ineeda Kasket was making her way through downtown Kokomo, Indiana when she began to notice a vibration in her month old Roth SL Coupe. Thinking it just a loose can in her trunk she ignored it and continued. Two minutes later she found herself sitting on the pavement with two broken legs as her car disassembled itself at a speed of 30 miles per hour. Happening at the height of rush hour and the Coupe still attracting attention witnesses were easy to come by and all stated the same, the car had broken apart. This instantly alerted the police and the state authorities that there may be something unusual going on and an investigation was started. The Kasket family also launched a lawsuit against the Roth Motor Company for damages after consulting with an engineer and a lawyer.
The Roth SL Coupe was also beginning to falter in other arenas as well. The nascent automotive press of the time finally were given the chance to test drive a production car with no distractions after a disgruntled owner who was sick of transmission fix promises volunteered his car. The Coupe was taken to the Sebring Raceway in Florida and for 2 and a half days in the last week of May 1962 various groups of journalists flogged the car over the track and surrounding roads.
On Day 1 of the testing the following notes were made by the late Benny Burble of our publication...
My colleagues and I are having the devil of a time trying to figure out if the SL Coupe got its transmission from a tank or a tractor, it surely was never intended for any car, that much is clear after the first shift... after you figure out where 2nd gear is!
All I can say is that 'SL' must stand for 'Slow and Loud', I love the sound of a good straight six engine and this is one of the best, but screaming at obscene revs at only 50MPH is a trial for anyone and most of the testers have resorted to plugging their ears as they lap the track here at Sebring.
Other comments made by the attending journalists were just as critical and the Roth SL Coupe soon earned it's nickname, 'Sloth' (1). The preproduction SL Coupe they had been allowed to drive by the Roth Motor Company had been excellent (2), they were all stunned.
Stunned became amazed during the morning of Day 3. A. J. Foyt had been invited to the track by one of the journalists and had taken to the track to lay down a hot lap in the Coupe. The car had now seen 2 hard days of racing and driving from the assembled crew and had already gone through one full set of tires. Midway through the second lap as the car rounded the last curve before the straightaway a loud bang was heard followed by a frantic call of a crash. As all in attendance ran to the scene they found Foyt sitting in the tall grass off the turn cursing at the top of his lungs surrounded by the remains of the Coupe. A.J. miraculously suffered nothing more than scrapes and bruises during the incident.
Immediately after Foyt was seen to the remnants of the car was moved to one of the garages on site for further study. A few of the people on hand held various degrees in sciences and engineering and they soon discovered that the car hadn't failed, as they had initially thought, at the connections between the panels... the body panels themselves had failed. Shear failures were evident in just about every body panel, the thin steel having been torn apart. Calls were made to government officials known to the assembled journalists while at the same time those same officials were beginning to hear similar stories from the officials of four separate states (3).
Due to the serious nature of these reports and the numerous injuries involved (4) a crash federal investigation was begun on May 20th 1962 and quickly discovered that the Roth SL Coupe was prone to stress failure of body components and had to be removed from the roadways of the United States immediately, this order was made official on May 28th 1962. Roth dealers nationwide were swarmed by angry Coupe customers and the legal team at corporate headquarters had no defense. The only stay they were able to obtain was that if the owner of any SL Coupe had the vehicle strengthened and certified by an engineer it could be registered and driven. At the time the cost to have this done was estimated at over four times the original purchase price. It was a hollow victory at best for the lawyers.
The Roth Motor company decided to issue a recall before public outcry made the government do so under possibly less painful terms. The cars were all bought back from their owners at the original price plus $500 per car or the same amount off the purchase price of a Roth sedan. Three days after the recall and buyback was announced in every major newspaper all but 5 Roth SL Coupes had been returned (5). Of these 5 cars 2 are still undiscovered and are rumored to be in the hands of collectors preserved in an unmodified state.
From records now accessible to the public and accounts of the Roth Motor Company employees willing to speak (or able due to still enforced legal rulings) we now know that management and design team pressure drove the engineering department to implement radical (for the day) engineering solutions on the Roth SL Coupe.
These techniques would be what the National Highway Traffic Safety Administration would focus on during it's investigation.
Roth Motor Company engineers created extremely complex mathematical models (run on two Word War II vintage analog ballistics computers converted for the purpose) to calculate precise panel thicknesses and frame strengths to maintain the shape and weight necessary to complete the design. At the time it was a great engineering reach only fully realized in recent years as CATIA design and manufacturing software became more commonplace in commercial applications.
Dr. James Timothy Possible, Rocket Scientist at the Middleton Space Center and former owner of a near stock 1962 SL Coupe explains...
It seems my 1962 Roth SL Coupe had never been modified in any way, I bought it out of a barn where it might have sat for 16 years. Before I began driving it all I did was clean it and put new tires on. Soon after that I discovered all of the flaws at once, while I was on a date with my now wife the car literally came apart. After calling my brother (Dr. Samuel 'Slim' Possible) and carting the various parts back to the family ranch we began to reassemble the car, correcting failure points as we went. The engineers at the Roth Motor Company were really on the right track and they had great ideas that are commonplace in any engineering field today but they didn't have the computers that we had even in the late 1970's to help them. I can only imagine what it must have been like trying to do such calculations with what was in essence a massive adding machine. The modified panels my brother and I ended putting in my 'Sloth' just to make it roadworthy added about 500 pounds to the overall weight, but since they were all distributed equally throughout the chassis it did not affect the already perfect 50/50 weight distribution.
The only engine choice for the 1962 model year was a 243 cubic inch straight six mated to a 4-spd manual with syncromesh gearsets.
Powertrain engineers at Roth had found a winner years before with their 'Stampede Six' used in most pre and post war Roth sedans. It was decided this same engine would be bored to a full 243 cubic inches displacement and cast from aluminum in order to raise power and drop weight. Newly dubbed the 'Express Six' and fed by three Veber side draft carburettors the engine was capable of close to 300 horsepower at around 5500 rpm. These numbers were excellent for the day and on paper it looked like the Roth Motor Company had a great product.
The letdown again came from the cost side of the equation, the aluminum castings for the engine left little money in the eyes of the accountants for a suitable transmission. They managed to acquire a supply of 4 speed manual units from Europe but misread the specifications. The transmissions were originally intended for delivery trucks in city areas and thus had gear ratios and a shift pattern wholly unsuited for the vehicle they were placed in. Memos from the engineering department to the accountants that survived to this day show that a near revolt was launched at what some engineers called the crippling of a potentially world beating car. In the end management sides with the accountants and the transmission was made to work with the Express Six engine. All of these compromises were noted at length in the official government report and to this day are taught to both engineers and business students as an example of what can happen when the need to control costs are taken to extremes.
After the disastrous government investigation and recall the sight of an SL Coupe was enough to send people running for the hills, faced with this the Roth Motor Company stopped production after only four months (6) and immediately turned the engineers that had remained at the company loose on the chassis and drivetrain while the old faithful styling of the latest model Firebrand mid sized sedan was converted to a coupe style to sit atop it. The resulting model while looking plain and rather homely by most design standards of the day was amazing on the road. The 'Express Six' now had a worthy transmission (a four speed manual sourced from American Motors Corporation under a new partnership) and a stiff chassis designed by engineers that had been left to do what they did best, build sturdy and rugged cars.
Released with little fanfare by a company unable to afford or risk a mass marketing campaign the new SL Coupe found itself tarred with the same brush as it's predecessor even though it bore no resemblance and only carried over the best components. Out of a production run of 1000 beginning late March 1963 only 200 new model SL Coupes were sold. The rest had their drivetrains cannibalized for Firebrand sedans, the bodies and frames were then crushed.
Stung by the failure of two high cost models and numerous legal actions the once solvent and respected Roth Motor Company fell onto hard times that only became worse as the era of the muscle car loomed on the horizon. The end came in November of 1963. As an extension of an existing parts supply contract the Roth Motor Company was folded into the American Motors Corporation (AMC) and it's models, the now wonderful SL Coupe included, were discontinued.
We leave this unique chapter in American automotive history with words from the sons of Dr. James Timothy Possible (Jim and Tim Possible) who transformed their father's near stock SL Coupe into what the car could have been, what they called the 'Sloth 1.0' specification...
Tim Possible (TP): Truthfully we didn't need to change much on the SL Coupe to make it a good car...
Jim Possible(JP): ... the basics were already there. I mean we told our sister we did this that and the other thing to the engine to make it more powerful but in truth all we did was...
TP: ... change from those antiquated carburettors to a modern multiport fuel injection setup with a new intake made on our CNC milling machine. The drivetrain was even easier...
JP: ... yeah, we're already designing our own cars for when we turn 16 and a dual clutch transmission has always been in our plans. It seemed and is a natural match for the Sloth 1.0.
TP: Our car monkey, I mean our sister Kim, says the car runs great and shifts very smoothly, lots of power as well. We replaced some ball joints, suspension arms and body clips with stronger composite parts and redid the interior but the biggest part of the car is still original, right down to the engine block and rigid cast oil pan. Jim and I really agree...
JP: ... this car was ahead of its time, and too soon all at once.
1962 Roth SL Coupe Specifications:
Weight: 3522 lb
Engine: 4.0 L (243 in³) Straight-6
Induction: 3 Veber Carburettors
Power: 295 hp at 5500 rpm
Torque: 304 ft·lbf at 3850 rpm
Top Speed: 112 mph
0-60 mph Acceleration: 11.1 s
4 Spd. Manual
Possible Special 'Sloth 1.0' Specifications:
Weight: 3800 lb (Estimate)
Engine: 4.0 L (243 in³) Straight-6
Induction: Custom Multipoint Fuel Injection
Power: 310 hp at 5300 rpm
Torque: 325 ft·lbf at 3620 rpm
Top Speed: 190 mph
0-60 mph Acceleration: 5 s
8 Spd. Experimental Dual Clutch Transmission
(1) It is unknown who coined the term 'Sloth', since the words 'Slow', 'Loud' and 'Roth' were in use frequently it's creation has been claimed by many.
(2) It was later revealed during the NHTSA investigation that the car tested was the prototype assembled by the Roth engineers themselves as a 'money is no object' option.
(3) Indiana, Colorado, California and Florida were the first states to send reports to the federal government.
(4) No fatalities ever occurred due to a Roth SL Coupe disintegrating although many serious injuries were reported, most broken limbs or flail chest.
(5) The 5 unreturned cars is over and above those that had already been destroyed in the known incidents and testing, those cars were crushed or left in pieces in junkyards.
(6) The line officially was shut down on May 28th 1962 but production had been proceeding at less than one percent capacity for an unknown amount of time before that.
AN: I had threatened to do this sooner or later. What do you think? I thought the 'Sloth 1.0' sounded like a Straight Six during 'Car Alarm' when Kim was just driving around town. I really got a partial 'DB5' feel from the Sloth before the Tweebs 2.0'd it... comments?