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?

Reply to
NewMan
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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.

Reply to
CAVHBC

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')

Reply to
Bill Putney

Bravo!!!

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

Reply to
Bill Putney

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')

Reply to
Bill Putney

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')

Reply to
Bill Putney

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

Reply to
Max Dodge

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.

Reply to
Max Dodge

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....

Reply to
Steve

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.
Reply to
Budd Cochran

Well said!!!!!

Bravo!!!!!

Reply to
Budd Cochran

Then you do not know all engineers, do you?

Reply to
Budd Cochran

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')

Reply to
Bill Putney

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

Reply to
Matt Whiting

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

Matt

Reply to
Matt Whiting

Thats acceptable?

Reply to
Max Dodge

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.
Reply to
Max Dodge

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.

Reply to
Budd Cochran

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)

Reply to
Budd Cochran

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.

Reply to
Budd Cochran

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