Just got back from a 3000 mile trip with the V-10 in my 31'
class C motor home.

Just like the first big trip, the engine continues to break in
slowly. 6000+ miles on it now.

The 4.60 gears mean you have to wind out the engine to get
anywhere. if you do wind her out, she pulls strong right up
to the shift RPM. Winding the engine also uses a little more oil.
Used maybe 1/2 quart in 3k miles.

Even at 13,000 lbs, it outruns all the semi's, most motorhomes
and some 4 cylinder economy cars up the long steep grades. Had
a silly toyota v-6 with oversized tires try to merge in front of me
on an uphill grade. I had to move over to let him in as I was already at WOT. He seemed shocked that he was falling behind - duh - those
big tires screwed up his effective final gear ratio and he just
did not have the torque at the tires he had from the factory -
especially with a v-6 doing the pushing.

On the very steepest portions of I 75 in the mountins, it would
drop into 3rd and fall back a mph if I was doing 65. If I was
running closer to the 3-4 shift point it would not fall back
and would even gain at 75 mph. Kind of odd since the torque is
dropping off at highest rpms. 99% of the time it would gain
speed anywhere in 3rd on any grade.

Good engine.

-Jim
2001 Cutaway E-450 31' superduty chassis

 

I've heard it said that "torque" is what gets you moving and "HP" is what keeps you moving. Perhaps this explains your 75mph experience?

 

Good point. What is implied but missing is the
qualifier from that statement. E.g. Peak torque
happens at lower rpms, peak hp happens at higher rpms.

-Jim

 

Torque: A measure of the tendency of a force to cause rotation, equal to the force multiplied by the perpendicular distance between the line of action of the force and the center of rotation.:-X23
Horsepower: The force required to raise 33,000 pounds at the rate of one foot per minute.
"How's That?":-staun

 

HP = (TORQUE X RPM) / 5252

 

[updated:LAST EDITED ON 14-Jul-02 AT 07:02 PM (EST)]?:-X23 Sorry, never heard that one before.

 

>HP = (TORQUE X RPM) / 5252

YUP!

 

Monsta......Cool lights

 

A dyno measures Torque, torque is easy a moment arm 1 foot long with a 1-pound weight is 1 pound-foot, increase the weight or moment arm length and increase the torque.

HP is 33,000 foot-pounds of work in one minute or 550 foot-pounds per second

To get from torque to horsepower, you need the "per second" term. You get that by multiplying the torque by the engine speed.
But engine speed is normally referred to in revolutions per minute (RPM). Since we want a "per second," we need to convert RPMs to "something per second." The seconds are easy -- we just divide by 60 to get from minutes to seconds. Now what we need is a dimensionless unit for revolutions: a radian. A radian is actually a ratio of the length of an arc divided by the length of a radius, so the units of length cancel out and you're left with a dimensionless measure.
You can think of a revolution as a measurement of an angle. One revolution is 360 degrees of a circle. Since the circumference of a circle is (2 x pi x radius), there are 2-pi radians in a revolution. To convert revolutions per minute to radians per second, you multiply RPM by (2-pi/60), which equals 0.10472 radians per second. This gives us the "per second" we need to calculate horsepower.
Let's put this all together. We need to get to horsepower, which is 550 foot-pounds per second, using torque (pound-feet) and engine speed (RPM). If we divide the 550 foot-pounds by the 0.10472 radians per second (engine speed), we get 550/0.10472, which equals 5,252.
So if you multiply torque (in pound-feet) by engine speed (in RPM) and divide the product by 5,252, RPM is converted to "radians per second" and you can get from torque to horsepower -- from "pound-feet" to "foot-pounds per second."

See more than you ever cared to know.

Why two different things James Watt wanted to know how much work his coal mining ponies were doing. He also said 1 hp is 746 watts (yes like his name) and 1 hp for 1 hour is 2545 BTU. OK I'll stop now

 

I think I have a headache

-V10gunner

'00 SD F250 Super Cab XLT, 4X2, 142"WB, 6.8L V10, 4R100, 4.30LS, LT265 tire upgrade, Camper Package, Dark Toreador Red over Silver, Line-X, Husky mud flaps, Snugtop Xtra Vision Cab-high shell, AutoMeter Tranny Temp Gauge, Banks Stinger and TransCommand

 

[updated:LAST EDITED ON 17-Jul-02 AT 04:05 PM (EST)]Me too The thing that I like best about all this is, that when I hook My RV to the back of my truck and push on the gas, she takes off like no other truck I have ever had,and she keeps on get'n up.
Ya gota love it.