
148 LIGHT AND HEAVY VEHICLE TECHNOLOGY
advantage of the latter type of joint is that it facilitates
correct alignment of the system, thereby relieving the
support mountings of unnecessary strain. A spring-
loaded version of the ball-and-socket joint has been
more recently used at the lower end of the downtake
pipe on some transverse-engined cars, so as better to
accommodate the rocking movements of the power unit
(Figure 7.11).
7.4 VACUUM GAUGE AND EXHAUST GAS
ANALYSER
Vacuum gauge
An old-established item of engine tune-up equipment is
the vacuum gauge, which in the hands of an experienced
operator becomes an exceedingly versatile instrument ...