M-body road trip success

Those who read what I did to my '86 Fifth Avenue may find this
somewhat interesting. I just took a 678 mile road trip to northern
Nevada via US 395 in the car, using cruise control, AC about 40% of
the time, speeds at posted limits not exceeding 65. Average max road
speed: around 62 MPH.

Vehicle/drive train: '86 M-body, LA roller cam 318, Holly "Carter
clone" 6280 feedback carb., A-904 trans with lockup converter. Basic
timing: 7° BTDC @ 630 RPM per California spec. Fuel: 87 average
octane "regular."

Trip plan: Lv Lancaster CA via north CA 14 to US 395 to the Nevada
state line at Topaz Lake and return. No local driving at destination
(just bicycling around the lake), no idling with AC on, no "warm up"
idling, etc.

Elevation at start and destination: 2580 and 5950 ft above sea level.
Maximum elevation: Conway Summit, 8130 ft. Route has three major
6-8% grades northbound.

Fuel economy going: 25.4 MPG
" " return: 28.9 MPG
Average: 27.2 MPG

All CA smog gear is working as per spec., as well, with no
disconnected EGR or other illegal mods.

The best mileage ever from this vehicle was a trip from Laughlin, NV
to Barstow, CA: 29.1 MPG, average max speed 55 MPH.

I think it's fixed. Why do newer, smaller models with V6s get worse?
One can only ponder, but the answer always comes back the same.

 

The '99-'04 M body cars would do better than that. I know my Concorde
would. It gets 26-28 on its daily 80 mile commute, 31-32 on non-stop
highway.

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

 

In too much of a hurry. I meant '98 -'04 LH bodies (300M '98-'04).

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

 

good post- he's trying to impress people with that rolling POS car that
is 20 years old- all of a sudden he's a "big USA car" man- when before,
all he talked about was his Honda.

His Honda has a 60 HP engine in it.

How much HP does this ' 86 Chrysler have, around 100 ?

this "Bob" guy obviously has no clue just how much further advanced
modern automotive technology has come. NOTHING has a carburetor on it
anymore- all the new cars are fuel injected. 30 MPG highway is the
norm, or better. Many get 35 MPG with 350 CID V-8's in them

 

Way back when I owned an M-body (83 Gran Fury) it would consistently
turn in about 20-23 mpg highway. They were definitely sleepers when it
came to efficiency. Chrysler always did build the best, even in the dark
dismal days of the 80s.

But it also had a 2.45 rear gear and couldn't get out of its own way
off the line (though the top end was darn near unlimited). My wife's 93
v6 LH would simultaneously out-accelerate the M-body, AND get better
mileage, AND has cleaner exhaust. I still like driving my 60s cars
because a) they really ARE more powerful than modern cars, and b) they
have style. But I'd never argue that they meet the same kinds of
simultaneous performance objectives (power, efficiency, emissions) that
is possible today.

 

True. Dad-in-law's '00 LH would get a reliable 30-32 on the highway,
but remember...this is a lighter, FWD car with a V6 and fuel
injection! The old M-body had a 318 and a 2 bbl carb! The V6, of
course, with it's more modern fuel and induction systems, would
actually produce more BHP than the 318s in the M-bodies. The later
Magnum incarnations of the LA engine would put them to shame, but they
only wound up in trucks.

 

My Honda gets better on the road (32-33), much better around town
(30.) Your point, as usual, is that you're simply a troll with no
knowledge, and you're still angry about my crushing of your eBay fraud
empire.

120. I don't require a car to be a "dick extension" like you do,
Noodles.

Try 20-25. The Chevy small block's a pig...always has been. Modern
V6s, yes. As Bill Putney says, the LHs were good on fuel economy
while providing good power and response. The later roller cam 318s,
while an improvement in emissions and economy, were lethargic in their
2 bbl version, which came in most M-bodies of that era. The 360 with
a Carter Thermoquad fixed the power, but tanked the economy. The 360
was standard only on the Fifth Avenue Brougham. They were good for
maybe 20-23 on the road tops, but produced good power. Most police
packages ordered in those days had special cam grind 360s.

The California Highway Patrol had fleets of 1980s Dodge Diplomats, and
a few batches came with a special version of the 318. Although
economy shot up, saving the state millions of dollars a quarter, they
couldn't chase an overpowered muscle car or a Euro sportster like a
Porsche. For that duty, the 5 speed Ford Mustang 302s were introduced
as an interceptor. Didn't really matter...maybe Porsche WAS faster
than Chrysler, but it sure wasn't faster than Motorola or a Bell
chopper! What the CHP liked about the Diplomats, though, was their
toughness and longevity, even though they were lacking in pursuit
power. The Mustangs barely lasted the two years duty cycle, while the
'92 Camaros were retired after 6 months due to high maintenance and
low reliability.

The Camaro also suffered from dangerous wet surface handling. Most
districts would "ground" the Camaros during rainy weather, as their
accident rate was 5 times the fleet average on slick pavement. I know
this well...my wife bought a '92 RS and the rear end would come
completely unglued on wet pavement, even with Goodrich T/As. She had
the 3.1 60° V6, which would turn in 30 MPG on the road and was a tough
little mill, but reliability of that car overall was fair to poor. I
got really tired of replacing speed transducers on the 4L60
transmission (later, lighter version of the THM700) at $78 a pop, too.
The 1980s vintage ECM was less than forthright on giving good
information for troubleshooting, as well.

 

I agree...the M-bodies were much maligned but really good, honest
cars, if not "flashy" like GM's FWD competitors.

I have the 2:45 Dana 44 rear end as well, and once the converter locks
up in third at 36 MPH, you just wait for awhile to get up to speed.
I'm no speed merchant, so I don't care. The point is exactly as you
state...even though Chrysler was reeling from almost collapsing in the
late '70s, they alway still did their best in terms of putting out a
good product, and their economy and emissions were far better than
what GM and Ford could offer in an RWD sedan at that time.

 

No Dana 44 in an M-body. Either Chrysler 7.25 (behind /6 engines through
1983) or Chrysler 8.25

They did *well* but not always their best. The M-body would have been
far better with a simple throttle-body fuel injection system, such as GM
was already using at the time on its high-end cars, and Chrysler was
already using on THEIR OWN 4-cylinder turbo cars. If you could take an
equivalent the nice engine management system that GM put on the Cad
HT4100 off that piece of sh*t engine and put it on the bulletproof 318
engine from an M-body, you'd have the mythical "good" 80s drivetrain
that never actually existed in any form. Of course anything beat Ford
screwing around with the "variable venturi" carb for so long, but I digress.

 

Actually, an LH car weighs about the same as an M-body. Maybe more,
mabye less- depending on trim level.
There are a few things about current (and within the last 10 years) cars
that people forget:
1) Interior plastic is actually a lot heavier than you'd think
2) Mandatory safety equipment is *heavy*
3) Optional equipment weight (8-way seats, ABS, etc.) adds up fast.

The M-body was always a lightweight car- after all the F/M/J body was
designed as an even lighter and more efficient replacement for the
A-body family of cars (Dart/Valiant/Duster/Demon), and that was
Chrysler's SMALL car chassis. The M became a "large" car only by default
when everything else shrank. And it was still smaller than contemporary
Ford and GM "full-size" cars like the Crown Vic, DeVille, Olds 88, etc.

 

Well my 2001 jeep still only gets 23 mpg as per a 2006 model so no
improvements at all even with a 6 speed gearbox and a cd stacker lol.
Lushy form AU

 

OK, it's an 8.25...but that housing sure LOOKS like a 44!

GM got into that trap on '80s 2.8 V6s, such as in the "Blazé," with
the Rochester Model VV. Barely passed smog even when new, and
troubleshooting was a nightmare.

 

All very true. Cash strapped Chrysler had invested heavily in the
K-car adventure and was more concerned at that time with stretching
that platform to get as much as they could out of it before going
forward, and Iacocca had already dictated that RWD V8 cars were
history, preferring instead to market the hell out of turbocharged
K-car stretches. So, the Ms got essentially a
rehashed/added-to/improved version of the "Lean Burn" box of the '70s,
which saw its last incarnation for the 318 in '87, if memory serves.

GM meanwhile adopted the never-really-very-good small block Chevy as
their "base" V8 for all lines after retiring the Olds V8 in '85, but
had superior EM systems already in place. Still, a contemporary base
Chevy Crap-ice with a 305, although more powerful due to TBI, couldn't
touch the 318 in terms of both economy or durability. An example
would be a '90 Crap-ice with 305 (most came with 350s as options), TBI
and the usual stuff. Best on road with that, even with fastideous
tuning and maintenance and egg-on-gas-pedal driving, would be around
20-23. Hell, a 318 equipped M-body would beat that easily, as I just
proved. Add to that that the rock solid LA could probably outlast two
Chevy rebuilds, and you have a superior product. The proof is I still
see quite a few old M-bodies soldiering on, usually beat to crap but
still going, while I haven't seen a running '90 Crap-ice in many
years...although many can be found in junkyards everywhere.

 

GM got into that trap on '80s 2.8 V6s, such as in the "Blazé," with
the Rochester Model VV.[/QUOTE]

No such thing. (VV)

The VaraJet was not a variable venturi carburetor.

Not really.

 

Well, since you mentioned that, I just got back from a 1000 mile roadtrip in
a 96 LHS. It got about 28, and that's the most I've ever gotten. I thought
that kind of invites comparison to the 5th avenue above. I didn't drive all
that fast, and that seems to help quite a bit. I was around 70 mph on
average, I guess. That's with the 24 valve 3.5, 214 hp. Probably more
horsepower than the M body that Bob has. It's geared extremely well, I
think. Not a bit too high for good acceleration. Rpms get well above 2500
on the interstate.

My 3.5 only gets 20 around town, compared to Bill's 26-28. It's interesting
to me that smaller new cars with similar horsepower to the 3.5 don't get
better gas mileage. We need to replace it, but nothing offers any
improvement except a much smaller car with less horsepower. Smaller cars
with more horspower, like a V6 Camry or Accord, for instance, get around
20/28 EPA ratings. It seems like they could do better.

 

So the car actually ran, and that's a "success" ??

translation:

#1- you finally changed the friggin' THERMOSTAT based on my posts, and
fixed the overheating/backflow into the radiator problem. This, after
tearing down the entire engine, including heads and oil pan/pump,
looking for the problem.

#2- you ran a straight vacuum advance from manifold vacuum to the
distributor, and bypassed the BS controls for the vac advance- like I
told you to- and the car runs better.

#3- you disconnected the EGR valve, and the car runs better, after
reading my posts about removing the EGR

you are such a wannabee....you deserve that shitbox

 

You're an idiot. Who'd listen to you? The thermostat in the car is
the same one that was there before all this began. I tested it, and
it tested fine, opening at 192°. Of course, an idiot like you
probably doesn't know HOW to test a thermostat, but...who cares?

WRONG. You get too fast an idle and illegal emissions.

A felony in all 50 states.

More projection from Charlie Nudo, who has been trying to get that
pizza chit Pontiac to run for years, but can't.

 

I'm wondering if either of you (or are you one person stalking
yourself?) have ever even laid hands on an M-body. 'Splain to me how you
run manifold vacuum to a distributor that doesn't have a vacuum fitting
on it. Unless its been converted to old-style Mopar electronic ignition
(which is as big an emissions no-no as disconnecting EGR, at least in
the eyes of the law although it probably does actually clean up the
exhaust compared to a non-functioning feedback computer).