National Post May 11, 2007
By David Grainger
Aerolithe Part Six
Ettore Bugatti made his company's name on the racing circuits of Europe in the 1920s with his brilliantly conceived straight eight engines.
In the beginning of the 1930s his competitive edge started to founder as other teams using newer technologies, most notably Alfa, Mercedes and Auto Union, started to crop up. A the time Ettore Bugatti shared many of the same racing philosophies as a gentleman in the United States by the name of Harry Miller and they spoke often by letter. Miller manufactured racing cars exclusively and his engines produced huge amounts of power in comparison to their displacement. He did this using a twin cam set up, one camshaft for intake and one for exhaust. This system produced far more power than the single cam units that were common to the day. Ettore looking for more horsepower from his engines bought a Miller engine and copied the twin cam design for his eight cylinder Type 59 3.3 litre racing car.
In typical Bugatti tradition the 3.3 litre racing engine with a few modifications to tame it a bit was used to power the Type 57 road cars.
The T 57 engine is true to the art forms established by Ettore Bugatti who always married form to function. It was a spectacularly beautiful creation which actually stands alone as an art piece. That it was an incredibly effective reliable and fast engine was icing on the cake.
Ettore Bugatti never had the huge sums of money needed to create mass produced cars without compromises. This is where he displayed his true brilliance. He often engineered designs that were beautiful and effective in yet were incredibly cost effective. Modern designers might find it prudent to take note. The cam boxes for instance, often touted as a brilliant piece of design, were quite simply put, just square cut flat planed, which meant that they were a lot cheaper and faster to produce and machine than other companies cam boxes which were curved and covered in swells and bumps.
In many cases the engines were polished and covered in both machine turning, a decorative finish of interlapping circles which was created using a drill with a course round felt pad, (rather like scotch brite) or ornamented by hand scraping.
Hand scraping which was considered a machinist's signature each man doing it having a different touch, was accomplished by laying a dull chisel on the aluminum surface and then striking it off and away with a mallet. It was a repetitive and time consuming process requiring hundreds or thousand of strokes. Despite this it was even seen on production engines as well as show pieces.
The T 57 3.3 engine, like everything that Ettore designed was subject to some eccentricities. One was that there was no head on top of the cylinder block. Instead that cylinder block was a solid cast. Ettore's thought on this were that if you have no head, you have no head gasket. No head gasket, no head gasket leaks. True enough and effective, but doing valve work necessitates a mechanic with small hands as the valves are accessed by removing the cylinder head from the engine block and then reaching up the cylinder bore from the bottom. Machining and adjusting the valves becomes quite an epic procedure and unlike many cars where the head is just quickly removed, the Bugatti engine requires the entire motor to be dismantled to access the valves.
The engine for the Aerolithe project is engine 45 that came with the chassis from the factory. It is in quite good condition but did require a complete and exhaustive overhaul. There is nothing worse than having a fully restored high points car stuttering and stopping and belching clouds of black smoke as it moves about the Concours lawn, especially if it has won an award. Despite this, you do get to see many show cars that can't make ten miles under their own power. I don't like creating them like that.
We decided that, while we had pistons and rings etc, we should change the out for new and cylinder head and block components were sent out for precision machining and fitting before coming back to the shop to be carefully measured, assembled and adjusted. The valves have to be very carefully shimmed and their tolerances measured as the motor is what is called an interference engine. Get it wrong by even a few thousandths of an inch and the piston comes up and smacks the valve into the next county. That is a very costly collision. Once the engine is assembled and every component has been tested, it is rolled over by hand to make sure that there are no sticking points and nothing evident that might cause an explosion when finally gasoline and spark are added to the mix.
Once complete it will be married to its already rebuilt transmission and then it will be started and run briefly on the bench. In the mean time I get to see it standing on its purpose built engine carriage, a magnificent creation that skillfully blended high art with superb mechanical engineering. Vive le Marque, Vive Bugatti.