G
Compression-Ignition Engine Replacement for Full-Size Pickup/SUV

The analysis and discussion for the main part of Chapter 5 were based on two vehicle classes—namely, a midsize sedan such as the Accord, Camry, Fusion, or Malibu and a midsize SUV such as the Durango, Explorer, or Trailblazer. To enable projections for the entire range of vehicle classes discussed in Chapter 9, it was necessary to create an additional engine specification to provide a CI replacement for the 5.3- to 6.2-L V8 SI engines which would be found in full-size body-on-frame pickup trucks such as the F150, the Silverado, and the Ram 1500 and SUVs such as the Expedition and Tahoe. Table 5.5 in Chapter 5 described a V6 CI engine with displacement between 2.8 and 3.5 L appropriate for midsize SUVs and midsize pickup trucks. For cost reasons, there is a range of displacements for which OEMs would tend to design and build V6 rather than V8 engines since V6s require fewer parts. For CI engines, this V6 range would be from about 2.9 L to perhaps 4.5 L. It was therefore assumed in this additional analysis that the V8 SI engines typically used in full-size pickups would be replaced by a V6 CI engine as long as the torque and power required for equal performance could be achieved. With a base-level specification at a specific torque of 160 N-m/L, the displacement required for a CI V6 to replace an SI V8 of the displacement range 5.3-6.2 L would be 4.4-5.2 L, which is really too large for the V6 configuration. However, from a cost point of view, the V6 configuration would be preferable to a V8 if a V6 concept could be identified that meets the requirements. If no base-level configuration were considered, an advanced-level V6 of 3.5 L could easily provide sufficient torque to replace a 6.2-L SI V8 and could be manufactured with the same set of tooling as the V6 engine whose cost increments are described in Tables 5.5 and 5.8. Therefore, for the full-size pickup class of vehicles, it was assumed in this analysis that the CI replacement for SI V8 engines would be a V6 of displacement up to 3.5 L with advanced-level technology. Cost estimates for such an engine are shown in Tables G.1 to G.3.



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G Compression-Ignition Engine Replacement for Full-Size Pickup/SUV The analysis and discussion for the main part of Chapter 5 in full-size pickups would be replaced by a V6 CI engine as were based on two vehicle classes—namely, a midsize sedan long as the torque and power required for equal performance such as the Accord, Camry, Fusion, or Malibu and a midsize could be achieved. With a base-level specification at a specific SUV such as the Durango, Explorer, or Trailblazer. To enable torque of 160 N-m/L, the displacement required for a CI V6 projections for the entire range of vehicle classes discussed to replace an SI V8 of the displacement range 5.3-6.2 L would in Chapter 9, it was necessary to create an additional engine be 4.4-5.2 L, which is really too large for the V6 configura- specification to provide a CI replacement for the 5.3- to 6.2-L tion. However, from a cost point of view, the V6 configuration V8 SI engines which would be found in full-size body-on- would be preferable to a V8 if a V6 concept could be identi- frame pickup trucks such as the F150, the Silverado, and fied that meets the requirements. If no base-level configura- the Ram 1500 and SUVs such as the Expedition and Tahoe. tion were considered, an advanced-level V6 of 3.5 L could Table 5.5 in Chapter 5 described a V6 CI engine with dis- easily provide sufficient torque to replace a 6.2-L SI V8 and placement between 2.8 and 3.5 L appropriate for midsize could be manufactured with the same set of tooling as the SUVs and midsize pickup trucks. For cost reasons, there V6 engine whose cost increments are described in Tables 5.5 is a range of displacements for which OEMs would tend to and 5.8. Therefore, for the full-size pickup class of vehicles, design and build V6 rather than V8 engines since V6s require it was assumed in this analysis that the CI replacement for SI fewer parts. For CI engines, this V6 range would be from V8 engines would be a V6 of displacement up to 3.5 L with about 2.9 L to perhaps 4.5 L. It was therefore assumed in advanced-level technology. Cost estimates for such an engine this additional analysis that the V8 SI engines typically used are shown in Tables G.1 to G.3. 177

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178 ASSESSMENT OF FUEL ECONOMY TECHNOLOGIES FOR LIGHT-DUTY VEHICLES TABLE G.1 Incremental CI-Diesel Engine Cost Estimations to Replace SI MPFI OHV Two-Valve 5.3- to 6.2-L V8 Engine in a Full-Size Body-on-Frame Pickup (e.g., Silverado and Ram) or SUV with a 3.5-L V6 DOHC CI 50-State Saleable ULEV II 3.5-L V6 DOHC CI-Diesel Engine, Baseline: Estimated Cost SI Gasoline OHV 4-V 5.3- to 6.2-L V8 Versus Baseline ($) Common-rail 1,800 bar piezo-actuated fuel system with six injectors (@$75), high-pressure pump ($270), fuel rail, regulator and 911 fuel storage upgrades plus high-energy driver upgrades to the engine control module. Credit for MPFI content deleted ( $48). Series sequential turbocharging: One VGT with electronic controls and one fixed-geometry turbocharger with active and passive 830 bypass valves necessary to match high EGR rates at low load conditions ($750). Water-air charge air cooler, circulation pump, thermostat/valve, and plumbing. Engine downsizing credit from V8 ($200).a Upgrades to electrical system: starter motor, alternator, battery, and 1.5-kW supplemental electrical cabin heater as is standard in 167 Europe ($99). Cam, crank, connecting rod, bearing, and piston upgrades, oil lines ($62) plus NVH countermeasures to engine ($47) and vehicle 194 ($85). 226 High- and low-pressure EGR system to suppress NOx at light and heavy loads. Includes hot-side and cold-side electronic rotary diesel EGR valves plus EGR cooler and all plumbing. Add remaining components required for advanced-level technology (details in Table G.3). 308 Emissions control system including the following functionality: DOC, CDPF, selective catalytic reduction (SCR), urea dosing 1,040 system ($363). Stoichiometric MPFI emissions and evaporative systems credit ( $343). 227 On-board diagnostics (OBD) and sensing, including four temperature sensors (@$13), wide-range air/fuel ratio sensor ($30), NO x sensor ($85), two-pressure sensing glow plugs (@$17), six glow plugs (@$3), and Delta-P sensor for DPF ($25). Credit for four switching O2 sensors (@$9). Total variable cost with credits for SI parts removed excludes any necessary transmission, chassis, or driveline upgrades. 3,903 NOTE: Aftertreatment system cost estimates reflect April 2009 PGM prices. Estimates derived from Martec (2008). CDPF, catalyzed diesel particulate filter; CI, compression ignition; DOC, diesel oxidation catalyst; DOHC, dual over head cam; DPF, diesel particulate filter; DPF, diesel particulate filter; EGR, exhaust gas recirculation; MPFI, multipoint fuel injection; NVH, noise, vibration, harshness; OBD, on-board diagnostics; OHV, over head valve; PGM, platinum group metals; SCR, selective catalytic reduction; SI, spark ignition; ULEV II, ultra-low-emissions vehicle; VGT, variable geometry turbocharger. a Credit for downsizing from V8 to V6 referred to DOHC 4-V V8 downsized to DOHC 4V V6. In this case, credit used by Martec was reduced from $270 to $200 since the parts removed from an OHV 2-V V8 would cost less than those removed from a DOHC 4-V V8.

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179 APPENDIX G TABLE G.2 Cost Estimates of Exhaust Emissions Aftertreatment Technologies Capable of Enabling Tier 2, Bin 5 Compliance Midsize Car Midsize SUV Full-Size Pickup (e.g., Malibu), (e.g., Explorer), (e.g., Explorer), Catalytic Device Sizing Catalytic Device Sizing Catalytic Device Sizing Based on 2.0-L Based on 3.5- L Based on 4.4-L (April 2009 PGM prices) (April 2009 PGM prices) (April 2009 PGM prices) Item ($) ($) ($) DOC 1 Monolith and can 52 52 52 PGM loading 139 200 252 DOC 2 Monolith and can Not used 52 52 PGM loading Not used 70 87 EGR catalyst Monolith and can 7 Not used Not used PGM loading 13 Not used Not used Coated DPF Advanced cordierite brick and can 124 270 270 PGM loading 131 26 33 NSC system Catalyst brick and can 114 Not used Not used PGM loading 314 Not used Not used SCR-urea system SCR brick and can 39 274 274 Urea dosing system Passive SCR 363 363 Stoichiometric gasoline emissions and −245 −343 −343 evaporative system credit Emissions system total 688 964 1,040 NOTE: This table complements Table 5.5. Compared to Table 5.5, the columns reflecting November 2007 PGM prices (Columns 2 and 4) have been removed and a new column, Column 4, was added. This column reflects the aftertreatment system cost estimate for the exhaust flow rates of a larger base-level V6 CI engine (i.e., 4.4 L) suitable for replacing 5.5- to 6.2-L two-valve OHV V8 SI engines with 3.5-L advanced-level technology CI engines. Note that, as discussed in Chapter 5, it was assumed that the aftertreatment component sizes for the 3.5-L advanced-level V6 are equal to those of a base-level 4.4-L V6 because the power levels for these two engines would be the same, thus requiring the same exhaust flow rates. All cost estimates are based on April 2009 PGM commodity prices. Column 4 provides the estimate used for the aftertreatment costs in Table G.1.

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180 ASSESSMENT OF FUEL ECONOMY TECHNOLOGIES FOR LIGHT-DUTY VEHICLES TABLE G.3 Estimates of Incremental Costs to Implement Developments Whose Estimated Fuel Consumption Reduction Gains Are Summarized in Table 5.2 Midsize Car Midsize SUV Full-size Pickup (e.g., Malibu) (e.g., Explorer) (e.g., Ram 1500) Item 1.6-L L4 2.8-L V6 3.5-L V6 Downsize engines 2-L L4 to 1.6 L, 50 75 75 Higher load capacity rod bearings and head 3.5-L V6 to 2.8 L, 4.4-L V6 to gasket for higher cylinder pressures (~$12.50/ 3.5 L cylinder) Two-stage turbocharger system 375 545 Additional air flow control valves, piping, cost of 0a additional turbo, water-to-air intercooler with control valve, separate pump Dual-pressure oil pump 5 6 6 Switchable pressure relief valve for high or low oil pressure Nonrecirculating LP fuel pump 10 12 12 Variable output LP pump controlled by HP pump output Low-pressure EGR — 95 95 Additional piping (~$20) and valves (e.g., integrated back pressure and LP EGR rate ~$75), much more difficult to package for V6 engine with underfloor DPF, cost for L-4 already included in Table 5.4 Direct-acting HP (maximum 80 120 120 $20/injector, benefits derived from combination injection pressures > 2,000 bar) of higher rail pressure and more injector piezo injectors controllability Total 520 853 308 NOTE: These developments are CI-diesel downsizing from base level to advanced level, thermodynamic improvements, friction reduction, and engine acces - sory improvements. Total for full-size body-on-frame pickup ($308 at bottom of Column 4) used in Table G.1. FC, fuel consumption. aTwo-stage turbo system already comprehended in Table G.1.