Does anyone have any comments about the following ?

SUFFIXES.

A type 35B, a car of uncertain parentage and previously owned by a friend carries the chassis plate 4483 which, according to David Sewell, is recorded in the “Factory Production Records” as relating to a type 30 (fitted with engine no. 437) which was delivered to Colonel Sorel in London on the 19th May, 1925.

Attempting to unscramble the history of the 35B I noticed in Antoine Raffaëlli’s book “The Memoirs of a Bugatti Hunter” that most early type 35s are listed as having been registered as type 30As. This designation carried on from the very first car registered on the 12th July 1924 through to 26th March 1926, i.e. for over 21 months.

This led me to consider the various letters added to the type numbers allocated by the Bugatti factory, and the abbreviations used on factory drawings.

A

The letter “A” is used simply to indicate an amended version of the original, basic design.

The amendments include :

1. A touring version of a sports car design, e.g. type 13A
2. A new chassis to replace an existing design, e.g. type 30A
3. An economy version of a racing car design, e.g. type 35A
4. A supercharged version, e.g. type 37A
5. An Americanised version, e.g. type 43A
6. A smaller capacity version, e.g. type 51A
7. A larger capacity version, e.g. type 57A
8. A road-going version, e.g. type 73A

AR
“AR” stands for “arrière” and is frequently used in handbooks and manuals to indicate the rear axle i.e. “pont AR”.
AV
“AV” is an abbreviation for “avant” and is frequently used in connection with the front axle i.e. “essieu AV”
B
“B” is used to indicate further variations from the original design.
The variations include :
1. A supercharged version e.g. type 35B
2. The production version of a previous design project, e.g. type 68B and type 73B.
C
“C” for “compresseur” is frequently used to indicate the supercharged version as in 57C and 57SC. Just to make things slightly more difficult, the factory also used the letters CP, (see below). However to confuse things a bit “C” also seems to refer to the 2 litre version of the racing models, e.g. 35C and the rare 51C.

CH
“CH” is the standard abbreviation on factory drawings and parts lists for the chassis.
CP
“CP” also stands for “compresseur.” Why this unecesesary complication was introduced we will probably never know - the supercharged type 37 was referred to by the factory using three different suffixes attached to the type no. i.e ; 37A / 37C / 37 CP.
CV
The French equivalent of horsepower.
C.V.
“C.V.” is the standard abbreviation on factory drawings and parts lists for the gearbox, i.e. ; “Changement des Vitesses”.
D
“D” is only known to have been used once. The 39D was the final version of the eight cylinder 1.5 litre Grand Prix car having the same bore and stroke as the normal type 37A (i.e. 60mm x 66mm) but being distinguished by its enlarged exhaust valves and modified cambox. Five cars were made in 1927 and competed in the Spanish and British Grands Prix.
Dir
“Dir”is the standard abbreviation on factory drawings and parts lists for steering components, i.e. ; “Direction”.
E
A letter used only once; to identify the rotary valve version of the 48.5 x 50 mm small car (or motorcycle) engine.
E.A.
“E.A” is the standard abbreviation on factory drawings and parts lists for the front axle, i.e.; “Essieu Avant”.
EMB
“EMB” is the standard abbreviation on factory drawings and parts lists for the clutch, i.e. ; “Embrayage”.
G
The suffix “G” was used only once – for the 57G , the 1936 Le Mans “Tank” based on a type 57S chassis.
L
The engines of several type 49 Bugattis have the prefix “L” (e.g L80, L328, L455 etc.) The significance of this is not known.
Mot
“Mot” is the standard abbreviation on factory drawings and parts lists for the engine, i.e. “Moteur”.
P.A.
“P.A.” is the standard abbreviation on factory drawings and parts lists for the rear axle, i.e. ; “Pont Arrière”
S
“S” when applied to the type 46 and 50 meant “Sport” but when applied to the 57 might have meant “Surbaissé”.
S40
The “S40” abbreviation related to a variation of the type 57 which probably existed on paper only. A 1936 brochure shows a four-seater car based on a 57S chassis with an alloy-block type 50B engine with a 4 litre capacity.
S45
The “S45” suffix was confusingly added to the 57 designation as part of a ruse to gain “homologation” for a racing special with a type 59 chassis and 4.5 litre type 50B engine.
SC
The “SC” suffix was applied to the supercharged versions of the type 57S.
T
“T” was first used in 1926 to denote the “Targa” model ; a full racing spec. type 35 enlarged to 2,300cc (60 x 100mm). Presumably the extra torque of the larger motor was thought to make the car more suitable for the demanding conditions of the Targa Florio. The next use of the letter was in 1933 when the “Touring” long-wheelbase type 50T was introduced. “T” was next used (in the UK) on the sporting type 57T also known as the 57TT and, by the factory, as the 57 GR. The final use was for the 74T design project for the mutiple use of the four-cylinder steam engine.
TC
“TC” stands for Targa Compresseur, a suffix applied to the 2.3 litre type 35 which was more commonly known as the type 35B. Their engines had the suffix “T”.
TT
“TT” stands for Tourist Trophy and was used for the type 57 variants prepared for the Ards Tourist Trophy in 1935. The suffixes “T” and “GR” were also used to describe the same models.



Type numbers and their suffixes are used in the following ways :

1. On factory drawings
2. In sales brochures and advertisements produced by the factory and its agents
3. Stamped on components



13A A touring version of the type 13 with a cast bulkhead.
30A A long wheelbase version with reinforced frame.
35A An economy version of the type 35.
35B A supercharged and enlarged version of the type 35. This designation was given to the model by the Molsheim design office. It was initially known in public as the 35TC (Targa Compresseur).
35C COMPRESSEUR i.e.supercharged version ; 2 litre.
35T TARGA. Version of the type 35 enlarged to 2.3litre.
35TC TARGA COMPRESSEUR. The supercharged version of 35T which soon became known as the 35B.
37A Supercharged version of type 37. Same as two cars listed below.
37C COMPRESSEUR. Factory designation for 37A
37CP COMPRESSEUR. Factory designation for 37A. For example, a photo in Conway’s “Bugatti” shows the right rear arm of a 37A clearly marked with the chassis no. 37283 and the engine no. 182CP
38A The supercharged version of the standard 38 intended to extend the
model’s life by the addition of the small type 39 supercharger. The last 50 or so of the 380 cars sold were so equipped.
38C COMPRESSEUR. As with the 37A the 38A was referred to by the factory as the 38C.
39A Supercharged version – 10cv – 160bhp (??)
39C A 60 x 66mm version of the 39A giving 126 bhp on Elcosine fuel.
39D A version of the type 39A with modified cambox and enlarged exhaust valves. Five built in 1927 for racing.
40A An enlarged and Americanised version of the successful type 40 using a type 49 block with its twin plugs, and a ball-change gear box produced in 1930 As with the type 38A, the production run was approaching 50 units.
43A A 1931 Americanised version of the standard 43 usually fitted with a two-seater and dickey body. About 30 were made.
43A Re-engined 16 cyl. version produced in1928
46S SPORT. A supercharged version of one of Ettore’s favourite models. Eighteen are believed to have been produced.
50B1 A significantly redesigned version of the type 50 motor : 4739cc, 84x107mm supercharged.
50B2 As above but only 4433cc, 84x100mm.
50B3 As above but only 2982cc, 78x78mm.
50B470D Designation for handed 50B aircraft engine – D = droit (right hand).
50B470G As above. G = gauche (left hand).
50BI A significantly redesigned version of the type 50 motor : 4739cc, 84x107mm supercharged.
50BII As above but only 4433cc, 84x100mm.
50BIII As above but only 2982cc, 78x78mm.

Note The same type 50B engines are referred to in different ways by different sources, e.g. The Bugatti Trust refers to 50B2 whereas Conway refers to 50 BII. Howevcer the latter use of Roman numerals would not be normal Molsheim practice.

50S Sports version of type 50. The engine drawings were prepared in January 1934 with the chassis drawings following from 10th October 1934.It had IFS and a V shaped radiator. Only one chassis was built before the project was aborted in favour of the type 57. It was however completed by the late Uwe Hucke
50T The 1933 long wheelbase (3.3m)Touring version of standard type 50. The last 20 type 50s built were to this specification
51A The 60 x 66mm stroke 1.5 litre, 158 bhp version of the 187 bhp 2.3 litre type 51 The 51A was produced between 1932 and 1936.
51C The 88mm stroke 2 litre, 165 bhp version of the 187 bhp 2.3 litre type 51. The 2 litre 51 was listed for sale from 1930 (for 165,000 fr. as against 140,000fr. for the 35C, but whether the C designation was used by the factory is uncertain.
57A The designation used on early drawings relating to the 3.3 litre production car to differentiate it from the earlier 2.8 litre prototype designs.
57B The designation attached to the series 1 chassis plans dated 18th July 1933.
57bis ‘bis’ refers to the second series.
57C The supercharged version of the 57 introduced in 1936.
57G Tank bodied 57S 1936
57GR A sports version of the type 57. The‘Grand Raid’ designation may be the factory designation equivalent to the T and TT suffixes used by the UK importer for upgraded 1935 Ulster Tourist Trophy chassis.
57S The lowered short-chassis version of the type 57 normally identified by its “V” shaped radiator
57S40 A design for a 4 seat sports car with a 57S engine and a 4 litre type 50B alloy block engine.
57S45 The 1937 enlarged racing version with a 4.5L 50B engine
57SC Supercharged version of type 57S
57T See 57GR above.
57TT See 57GR above.
59EB A design, presumably executed by Ettore personally for the fitment of a type 59 engine to a type 35 chassis.
68B A 369.5cc proposed production version of the original 318cc prototype engine fitted to the type 68.
68E A rotary valve version of the 380cc small-car engine,designed after Ettore’s death, by his son; Roland.
72B A revised design of the 1942/3 type 72 cycle engine project. Amongst the many revisions are a side mounted supercharger.
73A The road going single overhead cam version of the wartime four cylinder 1.5 litre concept
73B A redesign project carried out to improve the 73A (or the 73C twin cam design ?).
73C The 1945 supercharged twin cam racing version of the type 73 theme.
74T A design project to use the 1944 type 74 4 cylinder steam engine project in multiples of 2 or 4.
101C Supercharged version.of the 101.


Conclusions

1. There appears to have been no coherent thought given to the use of suffixes
2. Two or three suffixes were used to identify the same model
3. Suffixes were either letters with no significance used merely to denote a variation from the standard model e.g. 35A or the first letters of words denoting a variation e.g. 35T (for Targa).
4 Where model numbers are followed by letters with apparent gaps between them it would be reasonable to assume that the spaces were initially occupied by designations that were later abandoned or lost. For example, we know about the types 72 and the 72B. Surely it would be reasonable to think there would also have been a 72A. However, Sandy Skinner opines “The original T72 had a 22mm bore and a capacity of 10.6cc. There is probably no 72A since ‘B’ most likely stands for ‘bis’, literally ‘twice’ but also ‘the second one’, a usage which is common Bugatti practice.”


Further reading :

1. Letter from Henry Posner, Bugantics 52/4 p. 60.

Not for the T35C, there the C simply means "compresseur". At least in the beginning.


Not really. Until 1925 the Grand Prix formula was 2 litre, so Bugatti concentrated on this engine size. From 1926 to 1927 it was only 1.5 litre, so Bugatti followed this. The Targa Florio was an important event, but not held in compliance to the GP formula, so the engine was increased to the reasonably maximum size which was 2.3 litre.

The 2 litre models T35 and T35C were also still on offer, mainly for the Italian market where the 2 litre class was rather prominent. But also other buyers still preferred the T35C, some looked for class wins - especially at hill climbs -, others preferred the fact that its engine was revving more freely than that of the T35B.

The T35TC then was changed to T35B, simply to fit the gap between A and C. Over the years the T35C then became the synonym for "2 Litre", hence they used T51C for the 2 litre variant of the DOHC engine.