Technologies

Consumption Benefit

Incremental Cost

Comments

I4

V6

V8

I4

V6

V8

SI Techniques

(%) Range

(%) Range

(%) Range

Low

High

Low

High

Low

High

VVT—dual cam phasing (DCP)

DCP

1.5-2.5

1.5-3.0

1.5-3.0

52.5

105

105

  • Implementations include exhaust only and dual-cam phaser (DCP)

  • Manufacturer cost estimate of $35/phaser

Continuously variable valve lift (CVVL)

CVVL

3.5-6.0

3.5-6.5

4.0-6.5

239

308

435

465

525

585

  • Short durations may reduce pumping loss, and the reduced lift is a consequence of this

  • As intake manifold vacuum vanishes, alternate means must be found to implement power brakes and PCV

  • CVVL features wide range of cam profiles

  • Manufacturer cost estimate of $300 for an I4, and $600 for a V-8

VVT—coupled cam phasing (CCP), OHV

CCP

1.5-3.0

1.5-3.5

2.0-4.0

52.5

52.5

52.5

  • Requires in block cam phaser

  • Manufacturer cost estimate of $35/phaser

Stoichiometric gasoline direct injection (GDI)

SGDI

1.5-3.0

1.5-3.0

1.5-3.0

176

293

254

384

443

527

  • Enables about +1.0 knock limited compression ratio

  • High pressure fuel pump increases parasitic loss

  • Increased volumetric efficiency increases pumping loss

  • Injector deposits formed upon hot shut down has been a traditional concern

  • Manufacturer cost estimates $80/cylinder and $136 for injector noise abatement items

Technologies

Consumption Benefit

Incremental Cost

Comments

I4

V6

V8

I4

V6

V8

SI Techniques

(%) Range

(%) Range

(%) Range

Low

High

Low

High

Low

High

Turbocharging and downsizing

TRBDS

2.0-5.0

4.0-6.0

4.0-6.0

555

735

−50

308

788

1185

  • Vehicle launch performance will likely be compromised

  • Piston underside oil squirters, an oil cooler, and an intercooler may contribute to system merits

  • Dual scroll and VNT units will improve vehicle launch performance

  • Manufacturer estimates $550-$920 for a fixed geometry system



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