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-   -   How do YOU Pulse and Glide? (https://ecomodder.com/forum/showthread.php/how-do-you-pulse-glide-24180.html)

MisterInnovation 12-02-2012 09:55 PM

How do YOU Pulse and Glide?
 
There are several different ways of getting better gas mileage with the P&G, Accelerating faster to stay in the engine's most efficient rpm band, slow and steady, -5mph glide band, -10mph -15mph glide band.

How do you do it?

Pulse: I throttle up to 5000 rpm [My rebel's peak torque] and accelerate until I reach the seed limit or 55mph, whichever comes first.

Glide: I pull the clutch in and glide until I have lost 10mph or so.

Engine: On, Idling, in neutral(clutch in)

On hills I know, I accelerate down them if there is an incline at the bottom.
On hills I don't know, I glide clutch in. If I have to accelerate up a hill, I DWL.

I start coasting as soon as I can see the light is red, or if there is a hill approaching the light.

Stop signs suck.

How do YOU P&G?

serialk11r 12-02-2012 11:20 PM

My gears are too short, so I accelerate at 60-70% load to increase the pulse length and decrease the frequency of pulses. On hills, I accelerate slightly up them, into neutral down the hills (my car's terminal velocity on the steepest grades I've encountered in the Bay Area is about 50mph). I try to stay below 60mph because my engine's peak efficiency at 100% load is at 3200rpm (about 60mph). No vacuum gauge or load gauge, just butt dyno.

If the road is flat and there is a significant amount of traffic I don't pulse and glide, to be courteous to other drivers.

The last 1/3 of the Bay Bridge is a steep enough downhill grade so that the terminal velocity of my car is about 45mph, so I accelerate to 60mph and then engine off glide all the way down.

In the city I just stick it in 5th and let it roll at 20mph since I am too lazy to pulse and glide, and it wouldn't save that much fuel anyways.

user removed 12-02-2012 11:34 PM

On a bike I rarely P&G but I time the 46 lights on my typical daily commute and coast as much as possible. In my car or truck I coast a lot more. The grades here are never more steep than the downhill side of the overpass portion of an Interstate cloverleaf. My best gain is to draft-coast downhill on the Interstate. On route 143 which is 4 lanes not divided for 7 miles east of my neighborhood, I will coast down every downhill portion of that road, as long as I am not interfering with traffic. If someone is tailgating me and the left lane is open I might coast much further to get them to pass. I know every road around here from decades of driving them, and my routes will change depending on the traffic and even the day of the week and the time of day. Friday afternoon I take different routes to avoid the possible gridlock on the Interstate. There is a particular secion of road, with a 45 MPH speed limit where I can get exceptional mileage for 2 miles in any vehicle. I know when to accelerate to catch the green lights and when to coast up to the next light. I do not usually do engine off coasting, but I might try it in the Ranger on some stretches. In the Fiesta I am not about to do EOC with the automated transmission, just coasting in neutral, engine on.

regards
Mech

sbestca 12-03-2012 02:57 AM

I power up the hills keeping the engine in high gear if possible aiming to just match the speed limit at the top. Then I coast down the hills in neutral as far as it can take me to the minimum speed I can still engage top gear, about 30mph. If I have to stop at the bottom of a hill I leave the transmission engaged as this vehicle shuts the fuel off on deceleration.

Steve

NeilBlanchard 12-03-2012 01:47 PM

Almost exclusively, I use P&G to take advantage of hills or slight down slopes. I find it very hard to do on level ground, so that I can actually gain anything, so for me P&G basically overlaps a lot with coasting / EOC.

bestclimb 12-03-2012 02:58 PM

Pulse up hills glide down. The escort does not have a kill switch and it frequently has hesitations and/or stalls shortly after restart so it is mostly engine on (in the winter it is almost exclusively engine on unless it is a big enough down hill to really help, and the car is plenty warm inside).

sbestca 12-03-2012 03:34 PM

Hmm, about winter, sad thing about P&G is there is so little load on the engine I lose engine temperature. I worry about it getting cold enough to bring on enrichment. Grill blocking does not seem to be helping and I don't really want to block the rad itself. Usual summer position for temp gauge is 1/2. Winter has been 1/3 at 100kph. P&G seems to have it below 1/4 at 80kph max and -5c temps. Fuel mileage results not especially good but overall cold temps and snow have put a real kicking into any results.

Steve

D.O.G. 12-03-2012 10:02 PM

Quote:

Originally Posted by NeilBlanchard (Post 343276)
Almost exclusively, I use P&G to take advantage of hills or slight down slopes. I find it very hard to do on level ground, so that I can actually gain anything, so for me P&G basically overlaps a lot with coasting / EOC.

This is very close to my use of P&G as well. There are no flat roads long enough to get a good glide in both directions of my commute, I treat either direction of the same stretch quite differently.

brucepick 12-03-2012 10:20 PM

Quote:

Originally Posted by sbestca (Post 343298)
Hmm, about winter, sad thing about P&G is there is so little load on the engine I lose engine temperature. I worry about it getting cold enough to bring on enrichment. Grill blocking does not seem to be helping and I don't really want to block the rad itself. Usual summer position for temp gauge is 1/2. Winter has been 1/3 at 100kph. P&G seems to have it below 1/4 at 80kph max and -5c temps. Fuel mileage results not especially good but overall cold temps and snow have put a real kicking into any results.

Steve

A ScanGauge will show engine coolant temp digitally; I think UltraGauge will also show it. With that information, you can increase your grill blocking and other engine bay sealing safely. You need more information than what you get from a simple needle gauge.

You may need an engine bay belly pan or hood insulation to get engine temperature up where you want it.

YeahPete 12-04-2012 08:21 AM

Hills:
I pulse up hills 80% throttle. to 60-70mph depending on the length of hill. I make sure that I am going 5 mph over the speed limit at the top of the hill. I then coast all the way down until 40mph or I must begin another uphill ascent.

Flat:
I have noticed huge gains in my mpg once I started pulse and gliding on flat land that I used to just keep a speady speed of 50mph on. I also noticed any steady speed slower than 50mph netted worse mpg. With the speed limit 55 I pulse to 60, glide to 40.

Scanguage shows a .2 increase in my mpg EVERY pulse and glide I do on flat land. That is: at 50mph in the middle of my next pulse I have .2 mpg more than what I had in the previous pulse at 50mph.

Passing:
I stop pulse and glide to allow the driver 1 opportunity to pass me when there is no shoulder for me to pull onto. I go 5 under the speed limit for ~1 minute if there are no cars coming from the other direction. If the driver is too scared to pass, he gets to ride the roller coaster that is pule and glide until I feel there is a safe shoulder for me to let him pass.

My last 2 fillups were 45.35mpg and 42.something
EPA 23-33


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