

EPA is finally considering looking at the real value of stop start








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More than worth it?
By Shadowmaster625 on 12/31/2009 7:46:50 AM , Rating: 2
If your car gets 30 mpg, that costs about 10 cents a mile in the US. So after driving 50000 miles you've spent $5000. If you save 7 percent with stop-start, it means you've saved $350 after 50000 miles. Clearly, it is not worth the extra cost. Even if you did save money after 5 years of driving, you have to take into account your $500 five years ago is worth $650-$750 today. So the real inflation adjusted cost of stop-start is closer to $700 than $500. And you gotta pay tax and finance charges on that amount too. How does $800 sound? You'd have to drive over 100,000 miles in 5 years for this to pay for itself. But if you drove those kind of miles, they'd obviously be mostly highway, so your savings wouldnt be nearly 7 percent. Surprisingly, Americans are not universally stupid. There's a reason they dont bring this technology here; because its a ripoff. Gas needs to be well over $5 a gallon for it to make sense. And even then its only breakeven. Why pull forward your spending just to break even. Buying this technology, even if it does save a bit of money, leaves less money to spend elsewhere.

Not to mention you are increasing the wear on your starter motor, which could cause premature failure. So you may as well add an extra $20 to the price tag to cover the reduced average lifespan. Also, by stopping the motor you cycle the oil pump as well. And the timing belt. And many other systems that may or may not have been properly designed to constantly start and stop. Remember, it is the torque delta that causes most of the wear on belts, motors, and pumps. They all last much longer if run consistently at their optimum speed.

In the case of the oil pump, you are allowing oil to drain from the motor. So when it starts back up, the engine wear during those first few hundred cycles is going to be 1000 times greater than it would otherwise be. This will result in quicker loss of compression and deteriorating fuel economy in the later years of the engine's life, all but erasing any efficiency gains. Why subject yourself to all those additional risks just to save at most a hundred bucks IF (and only if) the price of gas were to go above $5 a gallon???? It makes absolutely no sense, in any country, under any scenario, and the people who brought this to market need to be fired.

RE: More than worth it?
By Shadowmaster625 on 12/31/2009 8:01:57 AM , Rating: 2
What if its cold outside? Are you going to sit there in traffic freezing your butt off because your motor stopped and you got no heat? Or if its electric heat, are you going to sit there and constantly drain your battery so that it needs to be replaced every 3 years instead of 5? Add another $20 to the price tag for that. And what if its 96 degrees outside? Good luck trying to run A/C off a battery... Yeah sure you could spike your A/C while the car is moving but then you are placing an extra load on both the motor and the A/C system while the care is trying to accelerate. There goes your fuel economy... Not to mention the lifespan of the coolant. Add another $20 to the price tag for that too. After all is said and done I bet the true average cost of this scam (with interest, amortization, tax, and increased component fatigue) goes over $1000. No one under any driving scenario, even a taxi cab driver, is going to save any money at that rate. Remember, most taxi cabs are bought with corporate debt issued at about an 8% rate. That ups the total cost of this option to well over $1000 not even counting component fatigue. So no, not even taxi companies would profit by purchasing this option. But I'm sure some of them will. (And they should be fired too.)

