Day Brown wrote in a message to Jim Dunmyer:
 DB>  On 09-19-97 Jim Dunmyer wrote to Roy J. Tellason... 
 JD> Absolutely not true, Roy. I've seen many articles in Popular 
 JD> Mechanics over the years, detailing how those sensors work, how 
 JD> to troubleshoot them with relatively low-tech equipment (a  
 JD> test light and DVM in many cases), and so on. You can buy a 
 JD> shop manual for an individual car for around $50.00, and  they 
 JD> have quite a lot of detail on the engine-control systems. 
 DB> ... 
 JD> That's because they finally have computers that actually 
 JD> control about everything on the engine, so there's a lot 
 JD> less plumbing and hoses strewn about. And it all WORKS; 
 JD> ...
 DB> Fur sure Jim; One problem I see is that as the sensor age, can  
 DB> the computer tell one is not reading correctly?  
That's a good point!  For one example,  I have heard mention in talking to 
some folks about this stuff that whenever you get a motor that's not been 
running right and you have to change some sensor or other you _always_ end up 
needing to change the oxygen sensor as well,  since it gets all gunked up.  
(Wonder why they can't make one that you can clean up?)
 DB> The car guys on PBS will talk about swapping out sensor stuff, 
 DB> but that can get very expensive very fast.  Even so, as you 
 DB> suggest, they are very efficient. perhaps the milage is worth 
 DB> it.
Yeah,  it's really something how you can get both better performance _and_ 
better economy out of a motor at the same time by running it right.  But it's 
not easy,  and I wonder about the reliability.
 DB> But, in 20 years, you won't find any 1990 antiques on the road; 
 DB> the deterioration of the plastic parts will be so onerous to go 
 DB> after to replace, and so critical to functioning, they wont.
Yep.  Like that noise that's been on the news lately about many failures in 
certain Ford vehicles caused by them placing some critical plastic assembly 
in a place that's just too hot for it.  Some engineers...
 DB> I heard the death knell of the IC vehicle power plant; they've 
 DB> applied computer chip plasma vapor deposition to batteries, and 
 DB> now have a lead cell with *twenty* times the power density. the 
 DB> range goes from 75 to 1500 miles/charge.  They also have 
 DB> designed charging controller chips to make sure the cells are 
 DB> not damaged by excessive charge rates, line spikes, etc. 
Wow.
 DB> NASA tech review has another rap about vastly cheaper fuel 
 DB> cells,  with high density, but lower output/minute.  Practical 
 DB> cars will probly use a mix, lead for passing or even takeoff. 
 DB>  
 DB> When it will really take off, is from the starting line at a 
 DB> drag race; the electric motors are getting much lighter, and 
 DB> with one on *each* wheel, you wont get the smoke from the rear, 
 DB> but you will get the 1/4 in the shortest elapsed time. 
What I have to wonder about this stuff,  though, is the economics of it.  
It's all well and good to show that it's *possible* to build a motor with a 
lot of power that's very efficient and light in weight,  but how much does it 
cost?  When they can start showing that costs are going to be comparable to 
what's out there now,  *then* we'll see things start to change.
Another consideration,  and one that I don't often see addressed with regard 
to electric vehicles,  is the power grid.  I can't remember where it was 
exactly,  but somewhere in my collection of Analog magazines there's an 
article that looked at that issue and came to the conclusion that in order to 
move to electric vehicles in this country we'd need to *double* the power 
grid,  in order to support current levels of usage.
email: roy.j.tellason%tanstaaf@frackit.com 
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