Italian engineering

The Slabang is a Swedish design intended to derive the maximum speed from a twinshaft engine. Very much like an enlarged Russian schools car, it incorporates a quite delicate front suspension controlled by nothing more than a single piece of piano wire. In the hands of Swedish drivers with much modified Olivers, or their own, home built versions these cars can regularly exceed 100mph. John Goodall described his own car that he used to break the 100mph mark, the only British person to achieve this. Now, Gianmauro Castagnetti has updated the concept by fitting fully damped, rear suspension, described and illustrated below. This design could equally well be adapted for any twinshaft car that has a suitable pan shape.

I started construction with a casting purchased in Sweden, I built the engine completely with the possibility of rotation and mounted a rear shock absorber. The body is made of fiberglass and is higher to allow the engine to be sprung. I will take it to Buckminster in June for use.

We met Gianmauro at Gt Carlton in 2019 where he had a bag full of original and historically important cars from Italy, France and the UK, as well as examples of his superbly engineered replica cars and engines. Communication was not easy but we are delighted at last to be able to feature a few of the engines he has built, mostly Oliver inspired.


Replica Oliver Tiger MkI RVB	Replica Oliver Tiger MkII	Replica Oliver integral gear motor


Parts count for the MkII	MkII crankcase	MkII on test rig


Replica ETI twinshaft	Exploded view of the ETI	Engraved logo rather than cast in

Oliver Twin Recreated. Gianmauro Castagnetti

When the MCA was set up, there was considerable disquiet about 'professionals' competing, primarily manufacturers such as the Olivers, father and son. By way of a protest, JO set to and built a 5cc twin based on two MKII Tiger units. The car was formed from hand beaten aluminium with the centre section removable for access to the motors and tank.

initially two separate fuel systems were used to get the tanks in the correct position, but by reversing one venturi, a single tank and cut off could be used.

The engine, in a later MI special survived and has now been built into a replica by John Goodall, that he ran on several occasions in 2023.

Photo right shows JO with the original car

Gianmauro has built this superb replica that included machining the entire motor from scratch.


Replica of the one-off 5cc twin built and raced by John Oliver


Superb reconstruction of the Oliver twin in a period style, cast pan, with a one piece GRP top

All photos supplied by Gianmauro.
©copyrightOTW/GianmauroCastagnetti2024

An Italian 'Sidewinder' Restored

Dear friends of “On The Wire” I would like to present a rarity worthy of being shown to all enthusiast of our beloved hobby.

My name is Franco Colla and I am writing from Italy, together with a group of friends we restored an old heirloom that belonged to a great Italian model maker named Carlo Saudella. We thought you might like to read the story of one of the greatest Italian speed flying champions together with the recovery.

Few months ago at a race Paolo Del Bianco, a well-know Italian speed flyer from Treviso surprised me, opening the trunk of his car showing a tether car in poor condition and telling me: “ you have the skills... please fix it!” This car in need of a deep restoration belonged to Carlo Saudella, he was an old friend of mine and also a great speed flyer who unfortunately passed away in 2010.


Unusual 5cc car in 'sidewinder configuration in need of serious restoration

I would like to briefly describe his career, he was born in 1924 at Fabriano and started aeromodelling with sailplanes , I have an old photo showing him at an competition in Rome , he was only 17 years old. In 1949 he build his first speed plane equipped with an ETA 6 engine build by Elio Tacchella. Also Elio was a good Italian speed flyer and owner of “Tacchella Machines” a company producing fine grinding machines , his mechanical skills allowed him to build model engines that were very competitive at the time.

Again back with Carlo …. he also started racing tether cars with a team of Ancona but there is little information about this period , I know he moved to Milan to seek better working conditions and in 1950 he was one of the competitors at “Giornate Ambrosiane” a prestigious and renowned control line race of the Italian championship. In this race he ranked 2^nd at 156 Km/h behind only Robert Manchon (CH) at 172 Km/h but with a more powerful 10cc Micron engine... old times and different rules ….

Carlo had a long break from modelling due to his marriage with Gianna and the birth of his daughter Loretta, moreover he changed jobs often. In 1958 he restarted speed flying competition for a short time using Super Tigre G24 engine and finally, after another stop for personal reason, in 1968 he was back again with freshly born OPS 60 engine from Gualtiero Picco.

The picture show him with his trophies, 7 Italian championship in 10 cc class , in 1983 at 52 years old he was the first to officially break 300 Km/h with two lines, to be precise 300,7 Km/h - FAI fuel – 100 gr/dcm2.

Right: Carlo at Piste il Monza 1971
Palmares: 1970 1st Italian championships 258kph
1971 8th Italian Championships 254kph
1972 1st Italian Championships 283kph

After this long and brilliant career at about 75 years old he honestly recognized that his legs become “too slow and tired for speed flying“ … so he returned again to tether cars. He was really very much “creative” giving vent to his imagination.

'Sidewinder' gearbox with suspension


Carlo Saudella's car, superbly restored


Raw castings	Finished car with suspension	Rear, fully damped suspension


Superbly engineered, home built twinshaft	Trunnions on the cylinder fins	2.5cc diesel twinshaft


Trunnion blocks	Rocker arm for damper	Adjustable damper in position