Frustrated with exaggerated efficiencies and BTU output?

iamlucky13 said:

I think it's more there's a tremendous difference in air quality when somebody runs a 5-15 year old engine vs. one made either in the last 5 years or more than 15 years ago

The latest regulations put a higher priority on nitrogen oxide suppression than on complete combustion. It alarmed me at first how many new-looking trucks I saw blowing visible smoke (but not enough that I think they were deliberately modded to "roll coal") until I looked into what the latest regulations were and what it takes to achieve them. In some instances, EPA regulations can represent significant progress. In some instances, they can make 2 steps forward and 3 steps back.

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The technology I work with is SCR. Using diesel exhaust fluid correctly means no EGR or particulate filter. That in itself is a step in the right direction. Tier 3 or tier 4 interim emphasized EGR usage heavily. Tier 4 final done right with SCR means a clean burning engine with longer service intervals because less contaminates in the oil and combustion chamber. Some manufacturers still struggle to grasp the benefits of SCR.

Same idea on a vehicles' mpg rating by the EPA.

It's on straight and level roads, clean pavement, and accelerating lightly.
Not the real world where people pass, or live in the mountain states where
vehicles start uphill sometimes, or have 4 200 lb peeps in the car.

CheapMark

CheapBassTurd said:

Same idea on a vehicles' mpg rating by the EPA.

It's on straight and level roads, clean pavement, and accelerating lightly.
Not the real world where people pass, or live in the mountain states where
vehicles start uphill sometimes, or have 4 200 lb peeps in the car.

CheapMark

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It's actually a dyno test running a series of specific speed and load profiles intended to somewhat mimic real world driving, with the load profiles based on measured aerodynamics and rolling resistance. The manufacturer tests the mileage to the EPA's test specification, and the EPA conducts their own tests on a few models each year to be able to enforce the testing accuracy. Kia and Hyundai both got in really big trouble for this recently, because they lied to the EPA about the load profiles, so when the EPA went to verify the tests on their dyno, they passed. Enough more customers than usual complained about getting bad mileage that the EPA did their own tests of aerodynamics and rolling resistance and found they falsified numbers that were artificially increasing the test mileage by as much as 6 mpg.

So no, it's not an exact real world test, but it's very consistent, so it's useful for comparing, and it is somewhat enforced.

For what it's worth, the EPA says my Honda Civic should get 30 mpg (combined). My long term average is around 37 mpg (I log fill ups and mileage). I've noticed the mileage has been declining as the car approaches 200,000 miles, and between the winter gas we're currently on and the predominantly city driving for my current job, the last few tanks have been only a little above 30 mpg.

My prior car (Corolla) should have gotten 29 mpg. My average was 40.5 mpg (yes, the engineer in me is obnoxiously obsessed with logging data).

So these are absolutely achievable, and even beatable numbers.

Me and my juvenile mind . . . still wondering why no one asked Stove about "heating his hoes."

It's tempting to chase numbers for products like this, but the reality is that by far, the most important variable in wood stove efficiency is the owner/operator. Trust me, I can take a published 80% efficient stove and make it into a 40% stove without even trying. All it takes is poor wood, poor technique, poor anything else. A few % points difference between models is insignificant in the real world, (at least when comparing similar technologies such as cat or non-cat).

Very few of us use our stoves in a closely controlled laboratory environment where the whole point is to be able to spec a couple of extra points for publication.