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Old 12-02-2008, 12:35 AM   #41 (permalink)
trebuchet03
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Quote:
Originally Posted by theunchosen View Post
Not true. . .It's per RPM which is not equal to horsepower. Go get tested. They will monitor your rpms and find out how much your outputting.
For consistency, the test is at a given rpm.... The standard doesn't need to be rpm based - it's simple a statistical control. So, if your particular year motor requires <500{unit} @ 2500rpm - that's what is tested. That doesn't mean the 500{unit} figure only takes rpm into consideration, it's a constant parameter calculated from some other function (power output, cc, class, etc. etc. etc.).

Getting tested won't tell you anything about how the standard was made I can buy a 12" ruler, but it won't tell me how the standard of one inch was developed

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All that said, last I checked, TierII emissions standards are in grams per mile. Weather or not you get 10mpg or 100mpg, the grams per mile figure does not change.

So yes, you might take a consumption hit - no, you won't put out more pollutants. The emissions standards control that

And on the Subject of consumption increase..... red= decrease from previous year - green = increase from previous year... I'm using the Jetta for consistency.
2009 Jetta Automatic Diesel 2.0L 29/40 enter Full TierII Compliance
2006 Jetta s6 Automatic Diesel 1.9L 30/38
2005 Jetta s6 Automatic Diesel 1.9L 30/38
2004 Jetta s5 Automatic Diesel 1.9L 28/39
2003 Jetta s5 Automatic Diesel 1.9L 29/40
2002 Jetta s5 Automatic Diesel 1.9L 29/40
1999 Jetta s5 Automatic Diesel 29/40 Prior to TierII Transition


OK, manual gearbox
2009 30/41 6 speed gearbox enter Full TierII Compliance
2006 30/37 5 speed
2005 32/41 5 speed
2004 32/42 5 speed
2003 35/44
2002 35/45 5 speed
1999 35/44 5 speed

2009 - 140hp
2006 - 100hp
2005 - 100hp
2004 - 100hp
2003 - 90hp
2002 - 90hp

Lets recap this timeline.....
Decent FE before TierII transition period begins in 2003
TierII Transition begins 2003 - no significant change in FE numbers
2004 - Horsepower goes up, FE drops
Tier II Full Compliance begins 2009
In 2009 we only see a drop in mpg for auto city by 1mpg, otherwise we maintain or gain with an additional 40 hp over the most recently retired diesel
1mpg, not even significant.....



I hear you (by you, I mean in a general sense) saying that emissions standards are killing FE for diesels.... I'd believe you if it weren't for the fact that emissions standards are NOT killing FE as according to fuel economy testing

Is fuel more expensive? Potentially accurate - it's hard to control economy statistics, but I'm inclined to think yes. But that's not the point I'm addressing which is fuel consumption with the addition of more stringent standards

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