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Old 12-16-2018, 03:46 PM   #6 (permalink)
slowmover
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Quote:
Originally Posted by matt36415 View Post
Is there a reason not to slow down to 60? Surely that would be the simplest and by far most effective way to reduce fuel use.

Out of interest, what are the speed limits there? In Aus the highest is 110kmh or about 67mph except some roads in the Northern Territory where pretty much no one lives.
The stupidity of todayís drivers cannot be overstated. Safety, vehicle longevity & reliability are out the window. FE doesnít matter either.

Following too closely is the worst (attended by the belief itís is legal to travel in the passing lane; it isnít) as under 300í space isnít cause for concern (it should be) and at 50í many will travel for miles. Hell, days.

NEVER EVER allow oneís self to be surrounded by other vehicles is the key. Ever heard the phrase, ďcanít fix stupidĒ? Thatís the guy inside any crowd. For any length of time.

When the morons are trying to form up, cancel cruise and drift down about 10-mph. Itís NEVER safe to have others around. Itís reason to hit the brakes.

Firearms and drunk teenagers. Thatís the EXACT risk analogy for trying to run at the upper limit. As nothing else in life has such life-changing consequences. An obese, alcoholic, chain-smoking desk dweeb will outlive the fools with firearms and bad driving.

Remember that at your funeral someone will tell the obese, alcoholic, chain-smoking desk dweeb that we are glad heís not as stupid as was the guy we are burying.

Traffic volume determines top travel speed. Which is almost never the actual limit.

That covers risk reduction. Spacing determines set speed, and is dependent on traffic volume. Always more than 300í. At 700í, relax.



Fuel economy is in steady-state cruise. Engage cruise control on the entrance ramp. Cancel it to drop off in speed when the fools gather around one (10-mph). Re-engage on a downslope where convenient. Itís always turned on and in use until the end (except the few times when cancellation is best).

With no acceleration or braking events, and maybe passing two-three vehicles on a 600-mile or 12-hr day (the maximum daily distance) the choice of travel speed will be likely be near 65-mph or a little lower.

The needed information is in average mph. The actual time of the trip. From engine start to car parked at dayís end. Total miles divided by time. It wonít be anywhere near travel set speed.

Thus the real trick to high average mph is

1). Location, number and length of stops.

2). Time of departure.

Letís do last first. Nationwide, traffic is lowest from 2300 to 1100. So start early. I start at around 0300. A good day for me in the Peterbilt is to have 500-miles done before noon. That happens only if everything goes well.

Planned stops. Always do this the night before. Zero unplanned stops. Itís every two hours or roughly 100-miles. A quick exit to the restroom is fine if some walking is involved.

Every four hours is a one hour break. Let this coincide with the fuel stop and/or meals.

The successful day is in knocking out those two-hour or 100-mile legs. What comes before or after is irrelevant. Skill in vehicle-handling is dependent on alertness. Fine motor skills. Without breaks as above (scientific study) those skills fall away. (Which is also accident avoidance).

Make the plan. Use Exit numbers. Stop point in the same direction of travel. No crossing major metro areas late in day. Etc.

These breaks arenít optional. Theyíre built-in to the successful plan.

Again, average mph: the higher the travel set speed, the greater will be the divergence between travel set speed and average speed. And the worse the economy. (Itís not all aero problems; itís in compounding them).

And that steering wheel corrections per 100-miles traveled is a valid FE marker, obviously lane-changing works against one. The more so in having to brake or accelerate to maintain constant speed.

I get drivers all the time on the CB complaining about slow trucks in their way. It shuts them up EVERY TIME when theyíre reminded their trip plan failed. Didnít leave early enough, either. You drive big trucks for a living and this becomes apparent right away. Every vehicle out there is constrained by safety (except in the pea brains of todayís car drivers; it was never this way until under twenty years ago).

A 4,000-mile trip is barely over a week for me. I average above 10,000-miles per month. Hit 120k for the calendar year last week. Habits and preparation are everything. Ronnie Reagan was in the White House last time I had a traffic ticket.

The miles around oneís metro area donít count towards anything. Itís all familiar. False bravado ensues on cross-country trips. There are differences from every geographical locale and state.

Whatís the real difference between running 62 or 72? The latter seems enjoyable because 90% of Americans report it as fully engaging. Any faster and the peripheral cone of vision narrows too far.

In other words, itís work.

At 62 one arrives relaxed. Thereís been no fight. Oneís peripheral vision includes the scenery. Itís what vacationing is about. At either speed itís still the rhythm of from one set point to another.

Whatís the time difference? Maybe the spread from 55 to 63-mph ON AVERAGE.

In other words, not worth the trouble to stay with the racing morons all day. I sincerely assure you thatís what they are. ******* children who never had parents. No baby daddy cared enough. Iím happy to tell father & son this, to their faces. Neither is father OR son.

The relation of guns to cars is that it only takes ONCE.

Talk of skill is a laughing matter. And irrelevant.

.
__________________
2004.0 DODGE Ram QC/LB 2500 2WD/NV-5600 305/555 ISB. 7,940-lb. Stock. 200,000 miles/5000-hrs @ 40-mph average.
1990 35' Silver Streak TT 7,900-lb.
11-cpm solo & 19-cpm towing; 21-mpg average past 54k-miles
Sold: 1983 Silver Streak 3411
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