Page 669 - Automotive Engineering Powertrain Chassis System and Vehicle Body

CHAP TER 2 0. 1 Vehicle refinement: Purpose and targets

Table 20.1-2 Some six-cylinder Ford executive cars (small) 1979–1999

Peak power Peak torque Estimate of real
Vehicle (bhp @ rpm) (lbft @ rpm) Weight (kg) Cost new cost in 1999*
1979 (no comparable model)

1989 Granada 2.4I V6 Ghia (Ref. e) 130 @ 5800 142 @ 3000 1340 £16 045 £25 996
1999 Mondeo 2.5 litre V6 Ghia X (Ref. f) 168 @ 6250 162 @ 4250 1408 £21 680 £21 680
1999 Mondeo 2.5 litre V6 ST24 (Ref. g) 168 @ 6250 162 @ 4250 1410 £19 680 £19 680

*Calculated in the same manner as Table 20.1-1.
References
(e) Test Update: Ford Granada 2.4i Ghia
Autocar & Motor, 11 February 1987
(f) Autocar Twin Test: Ford Mondeo 24v Ghia X vs Peugeot 406 3.0 SVE
Autocar & Motor, 6 November 1996
(g) Autocar Twin Test: Ford Mondeo ST24 vs Vauxhall
Vectra Gsi
Autocar & Motor, 22 April 1998

The exterior noise targets will mostly be objective It is not possible to determine a single set of such tar-
relating to the passing of the type approval noise test, gets for a given territory as every vehicle will have its own
although occasionally subjective criteria might be in- unique noise signature. This is made clear in Tables 20.1-2
cluded in addition (exhaust noise quality in particular for and 20.1-3 (see Section 22.1.1.6) where it is clear that the
sports cars). The interior noise, ride quality and tactile EU passenger car fleet exhibits type approval noise levels
vibration targets will be a mix of objective and subjective that vary by as much as 10 dB. Notwithstanding this, Table
criteria. 20.1-3 is offered as a starting point. If a particular vehicle
is diesel powered, perhaps the engine noise target should
20.1.6.1 Whole vehicle exterior noise be increased by 1–2 dB. If the vehicle is a sports-utility
then perhaps the tyre noise and transmission noise targets
targets should be raised by 1–2 dB apiece.

Whole vehicle noise targets are set in terms of drive pass
noise levels for the type approval test required in the ter- 20.1.6.2 Single component exterior noise
ritoryin which thevehiclewillbe offered forsale. Separate targets
noise targets are commonly set for each sub-system on the
vehicle. A typical set is given in Table 20.1-3 for vehicles In order to minimise the risk that the whole vehicle exte-
offered for sale in the EU. rior noise targets are not met at the final type approval

Table 20.1-3 Suggested target noise levels for achieving type approval under 9297/EEC. See Section 22.1.1.6 for further details
Passenger car Light truck Heavy truck
Target levels at 7.5 m, acceleration test (dBA)

Engine 69 72 77
Exhaust 69 70 70
Intake 63 63 65
Tyres 68 69 75
Transmission 60 63 66

Other 60 72 65
Combined level 74.2 77.3 80.1

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