No, I'm not. Look up any definition of efficiency. I will not involve
forces or torques (just force in a rotational form). It will involve
energy (or work or power). Gear ratios don't have efficiencies, that is
You are confused. You need to refresh your memory on some basic physics
And, again, I say you need to look up the definition of work and apply
it to both sides of your transmission. Assume for the moment that there
are no frictional losses since the discussion here is the gear ratio
itself. Now try different gear ratios and compute the work at the
output vs. the input and divide to get the efficiency. Show us how
different ratios change the efficiency. The only requirement is that
you must use the correct definition of efficiency, which you haven't
thus far. Look it up, it is in any high school physics book or easily
available via Google.
I didn't say you had to have written the reference yourself. Feel free
to post any link, book citation, SAE paper, whatever you like. It just
has to clearly say that gear or lever ratios change the efficiency of
Yep, another "I've lost and now how do I save face and get out of this
predicament" statement. There is no shame in being ignorant, but being
unwilling to learn is very shameful.
Indeed. It has been my experience that the problems usually arise when
MANAGEMENT overides Engineering - usually over "cost" issues. In
general, Engineers have a professional responsibility to do a good job
of design. Unfortuantely when Marketing and Management stick their
fingers in the pie, they often cut corners that should not be cut. If
they cut deep enough, you wind up with a recall. If they dig TOO deep,
then you wind up with a class action law-suit.
Saw it happen here a few years back. A Marine engineer was asked to
design a "fast ferry", which he did. After he completed the design, a
number of modifications were done as the ferries were being built. The
modifications were strictly pollitically motived by the local
government. Once the ferries went into service, they had no end of
problems. There was a huge public outcry. The government sued the
Lucky for him that he documents he work fully. When it got into court,
he proved that the design had been modified without his consultation
or permission. He also provided the analysis as to why the problems
were occurring, and what SHOULD have been done had he been consulted.
Unfortunately, the ships were already built, and were therefore
The case was thrown out, and the government went running with their
tail between their legs. It was so bad, they were thrown out of office
at the next election. It cost the taxpayers BILLIONS because these
idiots meddled in a process they knew NOTHING about. They did more
than cut corners. The resulting ferries were totally unsuitable, and
wound up being sold for little more than the value of the scrap
aluminim. They still sit by the shore today - shrink-wrapped and
If Management would listen to Engineering a little more often, then
they might spend a little more now, but in the long run they would
save a LOT of money. But Management does not see it this way. After
all, THEY when to management school to get their MBAsshole degrees!
Why should they listen to a lowly Engineer?
I was almost the fall guy on a commercial missile design disaster. I was
the electrical design lead on the missile, and the way the project was
being managed, I could see that there was going to be a disaster due to
lack of drawing controls and following the engineering design. After a
warning from God to get the h--- out of there, I insisted on being
assigned to another project even though I was threatened with having my
career wrecked if I insisted on that - but I did it anyway - God's never
wrong. Sure enough, two years later when they launched the rocket and
satellite, when the command was issued to release the satellite into
orbit, nothing happened. Seems the guy who took my place changed the
wiring of the various commands in the missile, and failed to inform the
software group (that programmed the computer to issue said commands) of
his changes. On top of that, when they completed the wiring and did the
functional tests, the tests results werent as expected - someone signed
off on the failed tests results and they went on their merry way. That
was a $650 million mistake. The next shuttle mission had to go retrieve
the 2nd stage and satellite and litertally manually separate them and
toss the satellite into orbit.
Paperwork in the company had been doctored to make it look like I had
left the project much later than I did. The lawyers got me into a room
and started grilling me on that. Foruntaely I had saved enough CYA to
prove otherwise, including the memo of agreement between the electrical
section and the software group on the wiring and commands. It never
went to trial.
The lawyers were funny. To soften me up, they started telling me a
bunch of lawyer jokes - we had some good laughs. All of a sudden, they
got real serious, and ask me how I would answer certain questions om the
stand. When they saw that my answers would be very incriminating to the
company, they tried to twist my answers. They'd say "You know - when we
asked you such-and-such, you said 'X'. Could you possibly say that
slightly differently, maybe like this...". I'd say "no", and they'd say
"Why not", and I'd say "because that would not be true.". Then they'd
re-phrase it one step closer to the truth, but still a lie, and I'd
still say "no". Then they brought out the falsified records showing
that I was on the project much longer than I was (i.e., when the
mistakes occurred). I presented my proof otherwise, and the meeting
ended abruptly - never heard from those nice gentlemen again.
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')
AH, Bill, you-da-man! Good job. I hate lawyers after the crap that
happend in my divorce.
Nice to hear that you managed (no pun intended) to avoid some nasty
But do tell, message from God? A dream perhaps?
(e-mail privately if you wish).
And you're an ass. ;) (there's the smiley to make the insult "ok.")
Yes, I'm a dreaded engineer too. But I also happen to be a
knuckle-bustin' "got grease in my thumbprints as I type this,"
do-it-myself car guy. The two aren't incompatible, you know.
Possibly true on paper, and spoken just like the lawyers intended. But
the background information is that that Chrysler didn't have *any*
"common" AC evaporator rot-through failures until the LH cars. I'm sure
some did fail, but not commonly. In 40+ years of having Chrysler
products in the family, I've had to replace exactly ONE evaporator core-
in an LH car. Statistically significant taken by itself? No. Significant
when combined with the acknowledgement by Chrysler engineers that there
WAS a problem with the early LH cores? YES! Now there were some valid
excuses for them. The LH car was the first Chrysler vehicle to get an
R-134a refrigeration system, and therefore the first car to get an
aluminum evaporator core. I'm sure it even went through and passed a lot
of accelerated corrosion testing... but there are cases where all the
testing in the world won't catch something that happens in the REAL
world where wall-clock/calendar time can't be simulated in the lab. Mold
and dirt stick to evaporators and over time do things that you can't
predict in accelerated testing.
But the bottom line is that once the company engineers realized that
there was a design problem, they really should have made it a lifetime
warranty on that part (one replacement per vehicle with the upgraded
part, trackable by the VIN) rather than saving a buck and losing a lot
of credibilty by essentially saying "Yes, that part is prone to
corrosion failure, but hey! Yours lasted out the warranty so you're SOL.
If it had failed 1000 miles sooner, SURE we'd have fixed it, but not
now!" Actually, I'm about 100% certain that if the decision had been
made by the ENGINEERS, they'd have done just what I said. But the
lawyers and accountants make those kinds of decisions. Oh, but I forgot.
We engineers are the bad guys that never get into the real world and
don't care about what happens after a design leaves our drafting
boards.... Sorry for not knowing my place...
And yet you're the one who's saying "Sorry pal, on paper the warranty
says 3/36 or 7/70... so the REAL WORLD fact that your evap core failed
for a known defect outside that period is irrelevant to me, I live by
what it says on paper." Not only are you an ass, you're a two-faced ass.
And I mean that the way it sounds.
As for your claim about it "usually being O-rings," well all I can say
in my case is that there aint no stinking O-rings in the big middle of
the evaporator core, and that's the place the oil stain was on mine. Do
O-rings leak? Yep, especially those crappy green HBNR ones that Ford
pushed for and have kinda become standard R-134a parts (get the
blue-coated type when you do R-134a repair work).
Wow....a sense of humor...not.
Nope...but being an engineer and being a fucktard are not imcompatable
either, as you just proved.
Thanks..nice to know that not all are nice guys.
and I mean BULLSHIT.
Difference is, I KNOW Im a ass, but two faced? Nope..
I can afford to replace the evap should it fail, when it fails and not bitch
about the warranty, and lets face it, thats what you are now crying
about....not the fact that someone that knows more about your issue with
your piddly ass evap core is calling you a wimp.
Couldn't have said it better myself.
It gets weird with the number of mechanics that have chips on their
shoulders about people with education and experience to back it up. Max
Dodge, this CAVHBC guy, and a few others in the past.
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')
No chip here. I'm sure the CAVHBC doesn't either. The problem comes up when
someone in the chain of important positions thinks someone else doesn't have
a clue, and bases it solely on the fact that they have more credentials,
rather than facts. Hence the regular occurrance of engineers getting
insulted by technicians when they plant the diploma on the desk as a defense
of their position regarding a problem in the field.
"There are four boxes to be used in defense of liberty:
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