P & G // W & S frequency

You can do as short of p and g as you want but you will get better FE the longer you make them.

 

There isn't really a time limit for P&G, you usually go by speed. I usually pulse to about 3MPH over the speed limit and then glide til about 2 or 3 under the limit (traffic and terrain dependent). The glide is much longer than the pulse. A 5 second pulse followed by a 5 second glide doesn't make sense. You would be gaining far more speed during the pulse than you would lose during that short of a glide.
One of the best ways to learn is to just try it and figure out what works best for you.

 

This link may not contain any new information but I thought it was well written. I don't do warp stealth unless I'm going down a slope. I don't see much benefit doing it on flat roads and definitely not good for up slope. If the slope is really steep and traffic condition permits, I put the car in neutral until the speed passes the speed limit by 5 mph and then put it back in "D". Before I put the car in N, I make sure that the fuel is already cut off to the ICE.

http://techno-fandom.org/~hobbit/cars/warpstealth.html

 

As long as the engine is running, you can shift into "N" at any speed. The car control laws will set the engine speed so no damage can be done. FYI, to get into "N" really fast, shift into "R" . . . be sure and do it while you have some in the passenger seat . . . say April 1st.

You want to avoid coasting down a hill in "N" with the engine off. If the speed builds up above 42 mph (earlier Prius) or 46 mph (current models,) there is a risk of over-speeding MG1. I've not heard of anyone 'grenading' their MG1 and I've been up to 10% over the limit. But it is not something one should 'tickle the Devil'.

Bob Wilson

 

The risk of over-speeding the MG1 (electric motor 1) comes from the risk of the MG1 overheating and then going bad - However, I also haven't heard or read of any cases of this happening.

 

my urban driving experience is that terrain - road surface limits is more significant factor than how long a pulse is is needed to glide for a fix time period. Driving uphill or in rough-grooved roads will limit any P&G pulse. P&G works best on a gentle downhill or flat smooth driving surface. Because you are sharing the road with others its best to control the P&G cycle using speed not time to determine when to initiate a pulse or glide. With a good downhill grade even a top speed of 65 mph can be maintain in a glide but on a flat road grade a top speed of about 35 mph is more sustainable in glide mode. As Bob has previously pointed out in other threads - The Prius' most fuel efficient speed is 25 mph.


1&2. No. For the most part, Warp stealth works at top speed closer to 40 to 55 mph. It also helps to have a scangauge2 and a very long (>.2 miles) smooth downhill dry asphalt road surface. WS top speed is limited by how long and how steep the downhill dry road surface is. Ive done WS over 55 mph but it requires a very steep downhill (West bound PA Turnpike) and it isn't very fuel efficient because aerodynamic drag eats up more than 50% of the Prius' energy unless you are drafting behind a truck which is problematic and possibly dangerous ( so its usefulness is very limited). If you are looking to get better super highway fuel efficiency the easiest way is to drive in the slow lane ( like the truck lane - where your speed is 60 mph instead of 80 mph ) .

My Prius is estimating that I'm doing 71 mpg over the last 300 miles which translates to about 68 mpg calculated at the pump. I've done better in the past at this time of the year but local driving conditions have gotten worse this year.

 

Sounds normal.

Hard rain, Snow and ice is bad news for your Prius' MPG - the tires slip a tad so the mechanical efficiency drops as your speed increases - dropping your speed when the road surface is slippery will reduce the loss in fuel efficiency due to the slippery road surface.


hope this helps walter

 

Sucks doesn't it? You can check your tire pressure to make sure its properly inflated but
since u were previously getting 67 mpg in good weather - I doubt there is anything wrong with your Prius' tire pressure. Overinflating your tires won't help (and can hurt ) the fuel efficency in this particular driving scenario because the energy loss is not caused by rolling resistance but because your tires are slipping on the road. The easiest solution is not to drive in bad weather - but normally that's not an option for most so the next easiest solution is to drive at a lower speed.

 

There are a few threads about how to safely put the Prius in N. You could put it in N anytime. However, on a down slope I make sure my speed is at least 50 mph before I put it in N. The reason is that on a down slope, my car may accelerate so I need to get the car above 42 mph to keep the ICE turning. I play it safe and wait until 50. On flat road or slightly up slope, I don't worry about the current speed because I know my car will decelerate in N.