Cruise Control for Long Road Trip

Irregardless of gas used, safety first, on a busy route using cruise control makes you easy to drive with, constantly changing speeds makes you a bit of a thorn, I'm uncomfortable with cars at 70ish when they aren't constant, just sayin'

 

Cite please.

 

This is the California law:
V C Section 22400 Minimum Speed Law
Minimum Speed Law

22400. (a) No person shall drive upon a highway at such a slow speed as to impede or block the normal and reasonable movement of traffic, unless the reduced speed is necessary for safe operation, because of a grade, or in compliance with law.
No person shall bring a vehicle to a complete stop upon a highway so as to impede or block the normal and reasonable movement of traffic unless the stop is necessary for safe operation or in compliance with law.
(b) Whenever the Department of Transportation determines on the basis of an engineering and traffic survey that slow speeds on any part of a state highway consistently impede the normal and reasonable movement of traffic, the department may determine and declare a minimum speed limit below which no person shall drive a vehicle, except when necessary for safe operation or in compliance with law, when appropriate signs giving notice thereof are erected along the part of the highway for which a minimum speed limit is established.
Subdivision (b) of this section shall apply only to vehicles subject to registration.

 

Rupert you beat me to it.

An officer will typically not pull you over until you are going 10mph over the limit.

Likewise impeding traffic by going 10mph under the speed limit.

Travis

 

Good try, but neither are valid and don't argue either point if you ever get a ticket, you will get the book thrown at you! California does not have specific speed limit requirements. We have that same rumor here in Georgia that they won't pull you over unless you are going 10 miles over the speed limit. It is absolutely false everywhere. They can pull you over when you are going a mile over the speed limit if they wish to. But, they are going to go for super speeders because those tickets are more difficult to get out of. Georgia has a 40 mph minimum posted on all signs. I know that it is in that range in most of the states here in the SE. They can only pull you over for going below the speed limit if you are impeding traffic. Is going 10 mph impeding traffic, not likely. But, say a tractor is on the highway and can only go 20 mph if that, they are going to be ticketed if they are in one of the main lanes and not on the shoulder.

 

I've seen some here say that the PIP should get worse mileage because of the heavier battery. Before the Prii, I drove VW TDIs and always beat the EPA mileages in them, too.

 

My Dad was a TDI owner Jetta sedan and station wagon before he moved on to the Escape Hybrid and now the C-Max. I think that if you are a hybrid driver or drive in a way that will improve gas mileage, you can get decent gas mileage with nearly any car. But, most hybrids are not great for driving long distances because gas mileage nearly always suffers. I am not all for giving it yet another reason to by using cruise control after being burned the time that I did shortly after I got the car. Same reason why I don't like my other half driving my car. He may drive a hybrid, but he is far from a good hybrid driver and my gas mileage suffers because of it. I am certain that some may get lucky driving with cruise control, but I don't. Luckily, it doesn't appear that I am alone in that. So, I would never recommend it. I probably will never have a PIP, so I have no idea how different things would be, but it would be interesting.

 

It would be interesting to know what your route was that you used the cruise control on so we could see the change in elevation from point A to Point B. Also, the speed that you had set your cruise control at and the conditions when you were driving (i.e. was it windy, rainy, etc...).

I have taken 2 long trips in my Prius Four since buying it a few weeks ago:

Trip A - From Lincoln, NE to Ellendale, ND and back. I set the cruise at 5 mph over the speed limit. It rained the entire drive and was very windy (mostly a cross wind). I averaged 45 mpg on that trip (most of it at 75-80 mph).

Trip B - From Lincoln, NE to Burwell, ND and back. I set the cruise at 3 mph over the speed limit. No rain or wind. I averaged 49.5 mpg on that trip (half highway at 63 mph and half interstate at 78 mph).

 

Are there any reliable mapping programs that show elevation? I know my running applications do, but I will have to research and see if google has some special feature. Can play around with them when I get home. There are really no flat routes around here, so I am certain elevation and grade has something to do with it. No different than running actually because you slow down going up hills, but can comfortably coast most of the time down them. At least that is the plan.

 

Are you talking about programs that you can just put 2 points in and have it tell you what the elevation would be? If so, not that I know of. You could probably download something like My Tracks by Google. It's a GPS mapping app and it will tell you the changes in your elevation along your route. I use that one when I'm running/biking, so I assume it works just as good when driving.

 

Yes, like the elevation charts I should be looking at before choosing to run certain Marathons. Found a way using MapMyRun. I mapped from Kennesaw National Battlefield to Charlotte, NC and there is an option that shows elevation using roads, then you can click a button to get the nice elevation chart. For my races, I typically use the Nike+GPS to give me that information, but MapMyRun seems really nice. Anyway, I typically go five over the speed limit, so I would have set the cruise control to 75. I can't seem to copy the chart and paste it here though...will play around a bit more. If anything, I found a good alternative to my GPS watch.

 

Go ahead and use CC! I did several trips in my 2010 Prius IV between SC and NY up I95 and back. Used CC whenever the chance presented itself. It helps keeps my speed steady and also prevents you from going too fast. I generally never went over 72-74 mpg and averaged 51-52 mpg round trip.

 

FIFY

 

Please Note: No mention of a "minimum speed" Only that you can't drive so slowly as to impeded traffic.

65 mph is the speed limit for cars on many California freeways. Is Froggytaco arguing that driving 55 mph would get you a ticket? That can't be right, because it isn't impeding traffic, and that is because there are maximum speed limits of 55 mph for trucks with 3 or more axles or cars towing trailers. Does that mean 45 mph is too slow? Maybe, maybe not. That is for the officer to decide.

 

I have been told by more than one CHP officer that they pull over for 10mph under and may cite depending on the conversation. YMMV.

Travis

 

Then those officers need to go back to the CHP Academy and take a remedial CVC class. There are laws against obstructing traffic, but unless there is a posted minimum speed, there is no law in California regarding driving under the speed limit.

 

We took the PiP from Wash DC to Biloxi Mississippi and back this March. Mostly Interstate going, all Interstate on return. I used the CC religiously, my son never does. Our PiP has the integrated radar-CC thingy which slows you down if the car ahead is slow. General speed: about 80 mph. Our mpg = low 50s there & back, about 2000 miles. Conclusion: CC doesn't affect mileage much at all in our experience. So, IMHO - it's really up to how the driver feels.

Also - the Prius speedometer is generous. I think SWAG 80 = 77 in actual speed. There's a threat on this topic here somewhere.

 

I'm a little confused about your post, because there is no context to it. Perhaps you could give a hypothetical example, say a freeway with a 65 mph speed limit for cars and 55 mph speed limit for trucks with 3 or more axles or cars pulling trailers.

What would be "10 mph" below the speed limit?

A) Is a vehicle, not towing a trailer, driving 55 mph driving 10 mph below the speed limit?
B) Is a vehicle, towing a boat/trailer, driving 45 mph driving 10 mph below the speed limit?

 

Done lots of long distance trips and cruise control is best. You still get good mileage and don't have to always watch your speed. Just watch out for down hills where the cruise can't hold it to the set limit.

 

I have a Garmin (just bought a new one to replace my five-year-old one) and it keeps a running display of the elevation. I have a very hilly 104-mile daily commute and the elevations vary between about 250 and 680 feet.

I use cruise control a lot especially if I have to keep up with the general flow of traffic. It's just too tiring and distracting to be constantly adjusting the gas and watching the display as I'm going up and down hill. Since I changed to Michelin Energy Saver tires, I've been getting 52-57 mpg (on the display) each way of my hilly trip using the cruise control most of the time.