1998 Grand Caravan

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
marine engineer.

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
unuseable.

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
collecting dust.

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?

 

Wow....a sense of humor...not.

Notice...no smiley.....

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.

bullshit.
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.

 

So the chip on your shoulders about engineers and people with eduation
in general is an act? I was beginning to think that Max Dodge had a new
posting identity.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Bravo!!!

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

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.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

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.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

No new posting identity here. Although obviously you've come off as a desk
driver again....


--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

It gets weird with the number of mechanics that have chips on their

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.

--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

Especially wierd since most of the engineers I know have a deep respect
for and trust the opinions and diagnoses made by good mechanics and
techs. Maybe "good" is the operative word there....

 

Well, would you want to talk about "engineering' and "common sense" instead?

As in; Overdrive transmission ratios are not efficient in comparison to
lower numerical final (axle) drive ratios combined with a direct (1:1)
transmission ratio. (Look at Archimedes' principles on leverage for the
clue.)

Or "if it ain't broke, don't fix it till it is" mentality coming out of
Detroit, Japan, Germany, Korea, ad nauseum. . . .namely, the A-604
transmission design.

It had potential, if . . .IF .. .they hadn't gone to an OD, if they had
given sufficient line pressures, if they had given it another underdriven
gear instead of the OD, if they had used a lower numerical drive axle ratio,
made it less sensitive to fluid type, given it more cooling . . . .

Think on this, Bill, I get 26 MPG highway out of my 95 3.0 Lebaron GTC . .
..not bad, not great. I squeezed 37 average MPG out of a 64 225 /6 (3 speed
manual, 3.23 axle, water vapor injection) and I got 21 average MPG out of a
79 D-150 (318, auto, 3.55, recurved vacuum advance), so what happened with
the GTC? By common sense, it should be getting near 45 MPG. IMHO, that
consarned OD is sucking up the fuel.

--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)

 

Well said!!!!!

Bravo!!!!!

--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)

 

Then you do not know all engineers, do you?

--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)

 

On the 300M Club forums, the accepted figure for the loss of power thru
the 42LE tranny (the next generation from the A-406) is a whopping 33%!

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

I'd like to hear your explanation on this. If the overall ratio from
engine to wheel is the same, why does it matter where reduction comes
into play?

I don't care about your opinion, but I am very curious to see your
technical explanation as to why you believe this to be true. Use
Archimedes or anyone else for that matter, but tell us your technical
explanation.


Matt

 

And you do not know the difference between most and all.


Matt

 

On the 300M Club forums, the accepted figure for the loss of power thru

Thats acceptable?

--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

I'd like to hear your explanation on this. If the overall ratio from

I don't agree entirely with Budd, but.....

If you put the engine first at a mechanical disadvantage (OD ratio) then
back to an advantage (rear axle ratio), you are sacrificing energy in the OD
ratio (more effort to move a load, due to mechanical disadvantage). This is,
I suppose, subject to mathematical calculations and would vary due to ratio,
amount of power input, load on the output end, etc. and could be extremely
variable.

But you won't get out of the parasitic loss encountered when you convert
rpm/torque once, and then twice, between engine and tire. A direct ratio
would eliminate one of the losses. As such, you've effectively lowered
useable hp at the wheel by using an OD ratio. Thus, it could be assumed that
you would use more fuel to make up for the loss in power, dropping MPG
figures.

So it doesn't matter where reduction comes into play as much as it matters
how many times you change the "reduction" in a drivetrain.

An interesting example would be my LeBaron GTC, where the 4th ratio is in
fact a mild OD (0.94) and the 5th ratio a normal OD ratio (0.69). MPG
between the two is not significantly different....at least, in several
checks over the years, the MPG indicator on the dash never changed
significantly (2 MPG or more) despite a ratio change with driving
conditions remaining constant, including road speed. OTOH, a shift down to
3rd would significantly lower MPG figures on the dash display. Take from
that what you will, I'll not claim any scientific structure.

--
Max

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)

 

Exactly the point I'm making!!!! If that's the loss in OD, then it's 1.65
TIMES the loss of a 727 or 904 in direct with a 2.76 - 3.55 : 1 axle. That's
gotta hurt economy.

That's not traditional Chrysler engineering. The 8.75 (8 3/4) axle had the
lowest internal friction losses in the industry, and, it'll make someone
mad, Ford had the highest with the early 9" that would burn up if run too
hard.


--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)

 

Have you ever heard of a guy by the name of Archimedes? Look up his
information on levers.

The same rules apply to gearing. An underdrive ration is like a prybar with
a long handle and a short span from pivot to load, a small force moves a
large mass. OTOH, an overdrive is like a short handle and a longer span from
pivot to load and requires much more force to move a small mass.

To make a OD work, the axle ratio has to be lowered and it doesn't quite
make up the losses in the drive train . . .it can't as that would violate
the laws of levers and physics.

"Give me a lever long enough and a place to stand and I shall move the
World." (Archimedes, if I remember the quote correctly)

--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)

 

Since a drivetrain is a proven to "lose" power to begin with, regardless of
ratios, adding a gear ratio that aggravates the situation is just plain
dumb.

I had three transmission choices on my Cushman scooter: simple centrifugal
clutch / jackshaft ( single overall ratio), a three speed ( low/direct/OD)
that would have required either gearing the final drive quite high
numerically (not feasible) or using a 1:3 underdrive input ratio, or a two
speed ( low / direct) with a 1:1 input ratio . . . .I went with the latter
since I only have 7 hp to work with and my estimated top speed is about 62
mph at 4200 rpm.

Choice number one gave a top speed of 41 and yet have good acceleration.
Choice number two gave a estimated 70 mph with a 1:1 primary belt ratio, but
that would have been only on paper. In reality, I don't believe I had enough
power to get over 30 mph in OD.

--
Budd Cochran

John 3:16-17, Ephesians 2:8-9

"Our Constitution was made only for a moral and religious people.
It is wholly inadequate for the government of any other."
(John Adams)