11 replies to this topic

[robert dick]

The standard wheelbase of the 4.5-liter Bentley built between 1927 and -30 was 10' 10" = 330 cm.
For customers, a few 4.5-liters were mounted in shorter chassis, wheelbase 9' 9.5" = 298 cm, the standard wheelbase of the 3-liter.
But - as far as I known - all the 4.5-liter factory Bentleys had the longer wheelbase of 10' 10".
Was there a particular reason? The Le Mans regulations? The stability at high speeds?

[GIGLEUX]

In 1930, at Le Mans, Sir Henry Birkin and the Hon. Dorothy Paget entered three "Blower" Bentleys: UU5872, YU3250 and UR6571.
UU5872 started life in 1929 with a 10ft 10in. chassis and 4-seater body; in 1930 it was given a 9ft 9in. chassis, of which only nine were made, and a Vanden Plas 4-seater Le Mans body.
YU3250 was the first-ever "Blower" car, built from Le Mans 10ft 10in. wheelbase 4.5-litre raced by Rubin in the 1928 Brooklands Six Hours.
UR6571 was a 1930 9ft 9in. Le Mans 4-seater, raced in 1930 by Dr. Benjafield, and by Eyston and Wood in the Brooklands 500-Mile Race.

[Doug Nye]

Please gentlemen - there is not, and there never has been, any such animal as a '4.5-litre Bentley'.

It is, and it always has been, that wonderful mixed-standards Imperial/Metric hybrid - the Four-and-a-Half Litre Bentley.

DCN

[David McKinney]

Or even 4½

[robert dick]

Thanks for the data, Jean-Maurice.
We have to make every effort to assimilate the refinements of the English language and culture. Difficult, very difficult...

[dbw]

so how do we address that most appealing mutant...

three-fourandahalf ?

3-41/2

bitsa mongrel....

[David McKinney]

Depends on your keyboard
3/4½ if you can do it

[Roger Clark]

Originally posted by Doug Nye
Please gentlemen - there is not, and there never has been, any such animal as a '4.5-litre Bentley'.

It is, and it always has been, that wonderful mixed-standards Imperial/Metric hybrid - the Four-and-a-Half Litre Bentley.

DCN

What is the car featured in example 12 of Pomeroy's "The Grand Prix Car"?

[robert dick]

Originally posted by Roger Clark

What is the car featured in example 12 of Pomeroy's "The Grand Prix Car"?

Certainly the influence of the blower.

= = = = = = =

The bore and the stroke of the "Four-and-a-Half Litre" (and of the "Six-and-a-Half Litre") were quoted in millimetres, 100 and 140 mm. Did the Bentley design team use the metric system for the engine? Or did 100 mm stand for 4 inches (= 101.6 mm), and 140 mm for 5 1/2 inches (=139.7 mm)?

[GIGLEUX]

The Autocar, Feb 22nd 1929 issue, testing the 4.5 Bentley gave 100*140mm and 4398cc. This engine was issued from the 6 cyl which appeared in 1925 and had the same bore and stroke: 100*149 and 6597cc.

[Vitesse2]

Originally posted by robert dick


Certainly the influence of the blower.

= = = = = = =

The bore and the stroke of the "Four-and-a-Half Litre" (and of the "Six-and-a-Half Litre") were quoted in millimetres, 100 and 140 mm. Did the Bentley design team use the metric system for the engine? Or did 100 mm stand for 4 inches (= 101.6 mm), and 140 mm for 5 1/2 inches (=139.7 mm)?

According to a short piece in the July 2007 issue of The Automobile, Bentleys used metric measurements for both engines and chassis. However, "chassis drawings for coachbuilders were in inches, their traditional measurements."

This in reference to the 3-litre, whose 80 x 149mm dimensions equate to the quoted 2996cc, and quoting a tracing of a drawing of a 3-litre chassis, with dimensions in millimetres.

There's more (though not really Bentley-specific) regarding British manufacturers and their use (or not) of the metric system.

Also referenced is Donald Bastow's "WO Bentley, Engineer".

[robert dick]

Thanks for the links; Richard.
Quite interesting that Bentley used metric measurements for the engine AND the chassis.