Edmunds Answers



  • karjunkie 06/30/09 3:09 pm PST

    The EVs are vehicle emissions standards in the State of California, but have gained popularity because they're easy to use. Here's what the different standards refer to:

    Low Emission Vehicle (LEV): This is the average vehicle, the minimum that you can legally drive in California.

    Ultra Low Emission Vehicle (ULEV): ULEVs are described as 50% cleaner than the average new vehicle for the model year.

    Super Ultra Low Emission Vehicle (SULEV): SULEVs are 90% cleaner than the average new vehicle for the model year.

    The 328i SULEV uses the N51 versus the N52 engine. In order to comply with SULEV requirements, the N51 is a variant of the N52 engine. Some of the SULEV measures for the N51 include:
    • Near engine catalyst with additional underbody catalyst
    • Secondary air system
    • Optimized combustion chamber geometry in cylinder head
    • Modified piston crown for lower compression
    • Plastic valve cover with integrated crankcase vent valve and separator (from N52KP)
    • Stainless steel fuel lines with threaded connections
    • Radiator with “Prem-air” coating
    • Throttle system - EGAS08 carried over from N52KP
    • Airbox with Activated carbon filter for EVAP control
    • Purge system pipes are made from “optimized” plastic

    BMW claims there is no performance difference other than the increase in weight which adds about 30 lbs.


Top Car Comparisons Experts View More

Rank Leader Points
1. texases 2710
2. Stever@Edmunds 2030
3. MrShift@Edmunds 1885
4. karjunkie 1830
5. morin2 1640
6. zaken1 1220
7. tony78 580