Thinking out loud, large cars

[Frank Lee]

They ain't no DOD on that.

[fjasper]

Originally Posted by Frank Lee

They ain't no DOD on that.

Umm, what?

[Frank Lee]

That Caddy has no displacement on demand. Where did you get that idea?

[fjasper]

I must have mixed up the limp-home mode (which does operate on fewer cylinders) with so-called "DOD" . That kind of makes it more impressive that it'll do 30mpg.

Sorry, when I see DOD, I think Department of Defense. The Cadillac is kind of a tank, and it's green, but I couldn't quite put it all together.

[Frank Lee]

My understanding of limp home mode is that it still runs on all the cylinders; it's just that they are alternatively fired. It works to prevent overheat damage by pumping cool air through all the cylinders. It wouldn't substitute for DOD because of the inefficiency of those pumping losses.

[mystere485]

A 300c with DOD has good potential for +30 mpg. Driving through interior British Columbia, from Abbotsford to Prince George, I managed to get 736kms from a full tank when the gas light came on. It calculated out to roughly 8.8l/100kms.

[fud2468]

IsaakC --I'll certainly agree the Dodges have powertrain problems (and paint problems) though where I live rust is not an issue. My first choice for both reliability and FE would be a Gen 1 Honda Odyssey which is a 4-cyl. but prices are very high.
As for CVs--Mystere485, as comptiger says, tall gearing is the way to go. Many non-cop cars came with a 2.73 rear and do the best, though some owners claim to do pretty well with 3.08 and 3.27 gears.
Cop cars with 3.55s are lucky to get 25mpg. Check your axle code to see what you have.
Some so-called "aero" ('90-'97) CVs had aluminum hoods and trunk lids, dunno if a '94 has them. The "whales" ('98 and newer) definitely did not and are a lot heavier.
Bigger tires-- Wouldn't they jack the car up higher and then there'd be no FE improvement? What do the experts here say?
Ray Mac

[mcrews]

fud said: Bigger tires-- Wouldn't they jack the car up higher and then there'd be no FE improvement? What do the experts here say?

It always helps if you read other threads besides your own.
OR when you do look at the posts....you read them........

ONE SIZE UP So this new areodynanic one seater your talking about......

oh wrong post....your the guy with the crown vic ..........
one size of tire up means....245/45/18 would be 255/45/18. the diameter is 3.4% larger. yes, I know that REALLLYYYY jacks up a car MAYBE 1/2 inch. ANd whern your've done SOOOOOOO much aerodynamic work on the nose cone and boat tail of the grand vic........

[fud2468]

I do read other posts but maybe I've missed some.
The ones I DO recall reading have said raising the vehicle increases aero drag and defeats the purpose, plus there's added weight.
Ray Mac

[mcrews]

Originally Posted by fud2468

I do read other posts but maybe I've missed some.
The ones I DO recall reading have said raising the vehicle increases aero drag and defeats the purpose, plus there's added weight.
Ray Mac

Well, congradulations.........

But for the thrid time let me AGAIN restate the post.

If you are going to go alot of hyway driving, go one size up on the tire (NOT THE RIM)
FOR EXAMPLE 245/45/18 would be 255/45/18 or an increase in the diameter of 3.4%.
Or about 1/2 inch taller.

And I really don't want to start hearing about drag and aerodynamics......
come on, the op is talking about a crown vic- not an award winner for aerodynamics... . THe gas mileage gain would far uot weigh any hypothetical loss of aerodynamics.

did you get that???

YOu blurt out some ramdom statement "JACK UP THE CAR" with out ever even THINKING about what was posted.
DID anybody advocate JACKING UP YOUR CAR? oh yeah.....you did.

And If you really have read the tire threads, you would see that a taller tire (up to a limit) is actually HIGHLY recommended.

So your next post better have a disertation on the effects of a tire that is 1/2 taller and barely 1/2 wider scientificly proven with ABA testing to have a negative effect of hyway speed mpg given the reduction inthe RPM at a steady 60mph.