LEV vs Euro3 emissions 2

[NeilRoshier]

is there a significant difference between the LEV touted by some japanese car makers for their recent vehicles e.g. Nissan VQ30DET LEV Cedric/Maxima and the Euro3 emissions standards. Specifically will a LEV meet Euro3?

 

[enginead]

There are anumber of differences between American (LEV) and European (EU3) standards that make them hard to compare. The first is the drive cycle used, US standards use FTP75 cycle consisting of 3 phases (cold transient, cold stabilised and hot transient) whereas EU standards uses a two stage cycle (urban and extra urban). The EU cycle is shorter and so the emissions from the first 100s or so before the catalyst is hot has a greater effect on the overall result. Also the FTP75 results are weighted for each part of the cycle so the final result isn't just a accumulation of the 3 phases divided by the distance travelled. Also important are on board diagnostic requirements which are different (and more stringent) in the US, which means that things like catalyst packages tend to be a bit better. The final point is the actual limits. EU3 are fixed for all passenger vehicles (although there are differences between diesel and gasoline) whereas for LEV there are a number of different derivatives (TLEV, LEV, ULEV and ZEV) with incrementally decreasing limits. To cut a long and complicated story a bit shorter, in my experience a vehicle that will pass EU3 would pass the TLEV standard without trying to hard whilst a vehicle that passes EU4 would pass LEV comfortably and vice versa. That's a bit of a broad brush statement but it's more or less correct.

 

[GregLocock]

Do you have the weighting factors for FTP 75? TIA

Cheers

Greg Locock

 

[Andy330hp]

For FTP 75 emissions, the equation is (using grams of HC as a "for instance", but same for HC, CO, and NOx)

[0.45*(grHC_cold505+grHC_860)/(dist_cold505+dist_860)]+[0.55*(grHC_hot505+grHC_860)/(dist_hot505+dist_860)]

Excuse the poor notation, if it's unclear let me know. Basically, the cold 505 is weighted 45% and the hot 505 is weighted 55%

Andy

 

[Andy330hp]

OOPS! Posted bad info. The 0.45 should be 0.43, and the 0.55 should be 0.57. Sorry!

Andy

 

[GregLocock]

Thanks. Is that the same for fuel consumption?

Cheers

Greg Locock

 

[NeilRoshier]

enginead thank you very much, very clear information. Australia is adopting the euro2/3/4 standards which will apply for all 'new' vehicles. From what you have said I should be semi-confident that the nissan engine that meets LEV will meet euro3/4?

 

[Andy330hp]

greg,
Fuel economy numbers do come from the FTP75, however I don't recall how they are calculated other than the fact the the city number comes from the 860 and the highway comes from the hot 505. My coworker (schmidtj86) had it in a book, but we can't find it!! I'll let know if we find it

Andy

 

[MMurphy]

City and highway fuel economy are weighted 0.55 and 0.45, respectively.

See

http://www.epa.gov/otaq/cert/mpg/40p0600.pdf

http://www.fueleconomy.gov/feg/info.shtml#estimates

http://www.epa.gov/otaq/emisslab/methods/hwycol.txt

http://www.epa.gov/otaq/emisslab/methods/hwfetdds.gif

 

[NeilRoshier]

sorry enginead just reread you post and you've already answered my question, thanks again