FC 3208 NA Performance Data

[orbitalsolutions]

Hello, Jeff.

Thanks for the input. Your willingness to share expert information
speaks volums about the person you are, and is greatly appreciated.

Man, I want those 4.63:1 gears. I don't know if my face could hold
the smile I would have running down the interstatre at 70mph. I
actually looked at the Road Atlas to see how far I was from Holland
Michigan!

I try to avoid driving long upgrades as much as possible, serious
climbing probably represents less than 2 percent of the driving I
do. When I went over the top at Flagstaff I was in second gear
doing about 15 miles per hour. A trucker came on the CB radio and
asked me if the bus was on FIRE -- LOL. But the engine temp was
acceptable and the old bus growled right on over the top.

This made me feel good, slow as I was going, after I passed several
tractors that were pulled over for a cool-down. But I must admit, I
was envious when that WB40 came blasting by me like I was parked
and just disappeared in front of me.

I've seen your 77FC31 on your web site and think the paint job is
fantastic. That's a great looking 'Bird!


james
78FC33SB
Bull Shoals, AK


--- In WanderlodgeForum@yahoogroups.com, "Jeff Miller"
wrote:
>
> Not quite sure what doesn't add up, but something doesn't.
>
> At 2200rpm in 4th, 5.29:1 gears you should be running around
49mph.
> Certainly should get better than 10mpg at that speed.
>
> If your speedo and tach are accurate, then it would suggest that
you
> have between a 4.63:1 and 4.44:1 ratio.
>
> I ran a 4.63:1 in a couple of my 'Birds, including my '77
> FC31/3208na.
>
> It allowed me to run 70mph plus, and to get into 3rd gear at a
> higher speed for hill climbing. My speed over Mont Eagle actually
> increased with the taller gears.
>
> It didn't seem to impact my fuel mileage, since I was running
10mph
> faster most of the time the aero drag increase at least offset the
> lower piston travel/mile of the taller gears.
>
> This was running clean on a '77 with a well tuned Na. If I were to
> suggest gears for a much heavier coach like an '82, towing, it
> depends on the terrain you're traveling and what you expect from
> your coach. A couple of guys have gone to taller gears on the late
> Na, but remember that the '82 FC35 is the worst power/weight
> ration 'Bird made, you need to address that for performance also.
>
> On our '84 250hp FC35 the 4.63:1 gears were too short for
flatlands,
> I would like to have run 4.44:1 instead. The 4.11:1 on our '88 /
> 300hp was a bit tall, especially with the .83:1 overdrive and 12R
> tires, again 4.44:1 would probably have been optimum when towing
> with that rig.
>
> In all I feel that changing from 5.29:1 to a taller ratio (first
> step is the 4.89:1 such as in the '83-'86) is a substantial
upgrade
> to any coach unless you're really going to spend a lot of time
> climbing mountains. If climbing is your game, get a turbo engine,
> you can't afford to lose 3% of your hp for every 1000' of altitude
> with the Na.
>
> - Jeff Miller
> in Holland, MI
> (we have hills here too, but we fill them all with water)
>
>
> --- In WanderlodgeForum@yahoogroups.com, "davidkerryedwards"
> wrote:
> >
> > Good info, thanks for posting that. What effect do you think the
> > taller gears would have on top end power? In other words, would
> you
> > feel different if you were driving I-70 instead of I-40?
> >
> > Kerry
> > 82 FC 35
> > Denver
> >
> > -- In WanderlodgeForum@yahoogroups.com, "orbitalsolutions"
> > wrote:
> > >
> > > At 15,000 miles the valves have fully seated on the "New Cat."
> > >
> > > After running 1590 miles, on roads ranging from running east
on
> I40
> > > from Kingman, AZ to Flagstaff, AZ (Without having to stop to
> cool
> > > down). Taking secondary departures to see big meteor impact
> sights
> > > and the Hopi Indian ruins, along with the winding paths that
> weave
> > > through the Ozark Mountains, and other stop and goes, this is
> what
> > > the numbers say...
> > >
> > > The old bus has consumed 152 gallons of fuel oil. That equals
> 10.46
> > > miles per gallon, pulling a Ford Ranger with enclosed aluminum
> bed
> > > shell, loaded pretty much to the gills.
> > >
> > > The motor is currently down less than a quart of motor oil,
> (none
> > > has been added). That's why I know for sure the valves are
> finally
> > > comfortable.
> > >
> > > The majority of running time has been done at 2200 Rpm's at an
> > > average speed of about 60 miles per hour.
> > >
> > > All I can say is I want higher gears! My bus has the original
> 5.62
> > > (I think, or what ever Blue Bird put in it) They are too
short
> for
> > > sure.
> > >
> > > The only running gear modification I want to make is to get
some
> > > longer legs in the pumpkin. I am convinced that it would make
a
> > > HUGE difference.
> > >
> > > Hopefully, I can find a garage that I feel comfortable to do
the
> > > work. I would have it done tomorrow If I could.
> > >
> > > Can't wait to see what the cruise speed will be at 2200 rpm's,
> or
> > > the fuel milage at reduced revolutions.
> > >
> > > So there are some real world numbers for anyone that may find
it
> of
> > > interest.
> > >
> > >
> > > James
> > > 78FC33SB
> > > Bull Shoials AK (But feeling ready for a drive)
> > >
> >
>