M-body road trip success

Discussion in 'General Motoring' started by DeserTBoB, Sep 11, 2006.

  1. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 11, 2006
  2. DeserTBoB

    Bill Putney Guest

    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

    Bill Putney
    (To reply by e-mail, replace the last letter of the alphabet in my
    address with the letter 'x')
    Bill Putney, Sep 11, 2006
  3. DeserTBoB

    Bill Putney Guest

    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')
    Bill Putney, Sep 11, 2006

  4. 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
    duty-honor-country, Sep 11, 2006
  5. DeserTBoB

    Steve Guest

    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.
    Steve, Sep 11, 2006
  6. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 11, 2006
  7. DeserTBoB

    DeserTBoB Guest

    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
    120. I don't require a car to be a "dick extension" like you do,
    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.
    DeserTBoB, Sep 11, 2006
  8. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 11, 2006
  9. DeserTBoB

    Steve Guest

    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.
    Steve, Sep 11, 2006
  10. DeserTBoB

    Steve Guest

    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.
    Steve, Sep 11, 2006
  11. DeserTBoB

    David Guest

    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
    David, Sep 11, 2006
  12. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 11, 2006
  13. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 11, 2006
  14. DeserTBoB

    aarcuda69062 Guest

    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.
    aarcuda69062, Sep 12, 2006
  15. DeserTBoB

    DeserTBoB Guest

    DeserTBoB, Sep 12, 2006
  16. DeserTBoB

    Joe Guest

    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.
    Joe, Sep 12, 2006
  17. DeserTBoB

    aarcuda69062 Guest

    aarcuda69062, Sep 12, 2006

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


    #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
    duty-honor-country, Sep 12, 2006
  19. DeserTBoB

    DeserTBoB Guest

    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.
    DeserTBoB, Sep 12, 2006
  20. DeserTBoB

    Steve Guest

    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).
    Steve, Sep 12, 2006
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