Pulse and Glide
#1
08-05-2005, 06:46 PM
Join Date: Apr 2005
Location: Jacksonville, FL
Posts: 335
Pulse and Glide
Forgive me for missing the boat on this one, but I have no idea what the pulse and glide technique is at all, so if there's anyone out there who can explain the strategy and doesn't mind taking the time to do so, I'd appreciate it a ton.
#2
08-05-2005, 07:23 PM
Re: Pulse and Glide
No problem
It varies a little between the different cars but the basic idea is to get up to speed (40ish) using a "Pulse" and then by some means turn the ICE off and "Glide" down to perhaps 30mpg and then do it again.
It varies a little between the different cars but the basic idea is to get up to speed (40ish) using a "Pulse" and then by some means turn the ICE off and "Glide" down to perhaps 30mpg and then do it again.
#4
08-05-2005, 07:27 PM
Ridiculously Active Enthusiast
Join Date: Mar 2004
Location: Atlanta, Ga
Posts: 1,797
Re: Pulse and Glide
I haven't used it myself for lack of any flat areas of significant distance. I'd be running into my next hill.
The last 14 miles or so on my way home at 3:00AM is mostly downhill and I'd say at least half is spent rolling in reboot. I don't suppose that will quite qualify as P&G.
The last 14 miles or so on my way home at 3:00AM is mostly downhill and I'd say at least half is spent rolling in reboot. I don't suppose that will quite qualify as P&G.
Last edited by Hot_Georgia_2004; 08-05-2005 at 07:29 PM.
#5
08-06-2005, 08:03 AM
Join Date: Apr 2005
Location: Jacksonville, FL
Posts: 335
Re: Pulse and Glide
Thanks guys. 
I may well give it a shot. My commute to/from work is straight through downtown so that wouldn't work, but I think I can find plenty of instances in other driving where I could swing it, and it's all deathly flat terrain here which would bode well.
I may well give it a shot. My commute to/from work is straight through downtown so that wouldn't work, but I think I can find plenty of instances in other driving where I could swing it, and it's all deathly flat terrain here which would bode well.
#6
08-23-2005, 08:55 PM
Re: Pulse and Glide
I'm not sure if this qualifies as PnG, but I do things like go up to 40mph in a 35mph zone that's up-hill and give it just enough gas to slow the deeceleration as much as possible and ride it down to around 33mph, then start over. Often I can hold the mpg at 60 or better for most of the stretch instead of getting 40mpg to hold the speed constant.
#7
08-23-2005, 09:25 PM
Re: Pulse and Glide
What kind of acceleration do you guys use when pulsing? I assume you're not flooring it, so what do you use as a guide to maximize your mpg? Do you adhere to a max rpm, max mpg reading, etc.?
I'm not so comfortable turning the car off for that time - switching to neutral is iffy enough for me so I do that on downhills and long flats/downward slopes. It seems to help a little but if I'm not doing it constantly I suppose it won't have a big impact. I commute 80 miles on mostly vacant freeway so I could do it if I wanted to concentrate that much, but frankly at 160 miles a day, I'd sort of rather veg out. I've been averaging 42mpg overall with my mileage split about 90% cruise control at 75mph and 10% city and hill coasting.
I'm not so comfortable turning the car off for that time - switching to neutral is iffy enough for me so I do that on downhills and long flats/downward slopes. It seems to help a little but if I'm not doing it constantly I suppose it won't have a big impact. I commute 80 miles on mostly vacant freeway so I could do it if I wanted to concentrate that much, but frankly at 160 miles a day, I'd sort of rather veg out. I've been averaging 42mpg overall with my mileage split about 90% cruise control at 75mph and 10% city and hill coasting.
#8
08-24-2005, 10:25 AM
Re: Pulse and Glide
Hi All:
___P&G is great for a Prius II and the other HSD equipped hybrids because they have this capability designed into them although I do not think Toyota thought it would be taken to the extreme at it has
Without ICE off, you probably aren’t gaining much over a straight “DWL”. Sirkut, that is what you are performing. The HCH, Insight, AH, and any non-hybrid has the crap beat out of them when running a continually repetitive P&G technique for any lengthy distance. The CVT based transmissions in particular and AS logic was not designed to perform this technique although it could have been …
___Hot Gerogia2004, using FAS’s like you always have mimics P&G with the hills but it depends on your speed range(s)? P&G keeps you within a very tight band in the HSD equipped hybrids for maximum effect. I still have my doubts about hills but given what was achieved a few weeks ago, use the ICE’s lousy efficiency to accelerate on the flats and climbs where needed and let her glide down the backside all the while keeping within a relatively tight band truly worked wonders. FAS’ keep you in a much wider band (any top speed down to 0 in fact) with much higher top speeds when and where applicable. Another way to look at it, if you are outside lets say 25 mph on the low side and definitely 41 mph on the high end in the HSD equipped hybrid, you are in FAS territory. You can perform a FAS in a Prius II by throwing it into Neutral with a SoC above 3 bars and not pink and the rest of the ICE shutdown logic is made up. If you are within the speed bands and can keep up the repetitive nature, you are performing a P&G. In the HCH’s and Insight’s, any speed band will do but it has to be repetitive. It just isn’t as practical as you would have hoped in an IMA based hybrid or non-hybrid today is all. We will see what the 06 Civic has in store because with its EV mode, it may in fact be able to perform a P&G without all the tricks thrown at it?
___Zimbop, as mentioned above, you really do not want to subject your HCH to this technique for any lengthy period of time over the life of the vehicle. A FAS every 2 or 3 miles is one thing, a P&G sometimes as often as every 1 or 2 minutes is something the IMA based hybrids were really not designed for. In regards to the acceleration rates, I do not have any experience in the HCH with P&G although I hope to soon. In the Prius II, that ICE was so efficient no matter the rate of acceleration that it didn’t matter. You could accelerate at 40 - 50 mpg (slow acceleration per the instantaneous) or 17 - 23 mpg (relatively brisk per the instantaneous) and still nail an excellent segment as long as you received the Glide distance to offset the fuel burn on the Pulse and you performed the Pulse properly. You COULD NOT USE THE PACK for any acceleration/pulse and YOU MUST send current to the pack during any and all accelerations/pulses to maintain a std. 4 to 5 bars SoC in the Prius II. With the proper timing to avoid the lights, and a perfect P&G technique nailed down including some EV when necessary, you were guaranteed a 110 + mpg segment on that particular route when the temps were above 70 degrees. If I were running the HCH, I would keep my Pulse accelerations just below Pack use. I would need an hour or two to figure out what I would hope to be the best bands on the flats of an Illinois country road but that may differ vs. the hills and road you may be running in your area? I also do not think I would be P&G’ing from 55 - 65 and back either as the acceleration back up to 65 is a fuel sucking monster given you are in a very rough Aero-drag territory vs. a 45 mph top speed in a normal P&G in an HCH.
___I do want to add that when following Dan Kroushl in his Prius II (we were in the chase Prius II) during the last segment of the Marathon Attempt, it was very hard to detect that he was actually cycling through the speed range. The normal ebb and flow of traffic along the stretch of road near Pittsburgh simply fit the P&G style to a T.
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
___P&G is great for a Prius II and the other HSD equipped hybrids because they have this capability designed into them although I do not think Toyota thought it would be taken to the extreme at it has
Without ICE off, you probably aren’t gaining much over a straight “DWL”. Sirkut, that is what you are performing. The HCH, Insight, AH, and any non-hybrid has the crap beat out of them when running a continually repetitive P&G technique for any lengthy distance. The CVT based transmissions in particular and AS logic was not designed to perform this technique although it could have been … ___Hot Gerogia2004, using FAS’s like you always have mimics P&G with the hills but it depends on your speed range(s)? P&G keeps you within a very tight band in the HSD equipped hybrids for maximum effect. I still have my doubts about hills but given what was achieved a few weeks ago, use the ICE’s lousy efficiency to accelerate on the flats and climbs where needed and let her glide down the backside all the while keeping within a relatively tight band truly worked wonders. FAS’ keep you in a much wider band (any top speed down to 0 in fact) with much higher top speeds when and where applicable. Another way to look at it, if you are outside lets say 25 mph on the low side and definitely 41 mph on the high end in the HSD equipped hybrid, you are in FAS territory. You can perform a FAS in a Prius II by throwing it into Neutral with a SoC above 3 bars and not pink and the rest of the ICE shutdown logic is made up. If you are within the speed bands and can keep up the repetitive nature, you are performing a P&G. In the HCH’s and Insight’s, any speed band will do but it has to be repetitive. It just isn’t as practical as you would have hoped in an IMA based hybrid or non-hybrid today is all. We will see what the 06 Civic has in store because with its EV mode, it may in fact be able to perform a P&G without all the tricks thrown at it?
___Zimbop, as mentioned above, you really do not want to subject your HCH to this technique for any lengthy period of time over the life of the vehicle. A FAS every 2 or 3 miles is one thing, a P&G sometimes as often as every 1 or 2 minutes is something the IMA based hybrids were really not designed for. In regards to the acceleration rates, I do not have any experience in the HCH with P&G although I hope to soon. In the Prius II, that ICE was so efficient no matter the rate of acceleration that it didn’t matter. You could accelerate at 40 - 50 mpg (slow acceleration per the instantaneous) or 17 - 23 mpg (relatively brisk per the instantaneous) and still nail an excellent segment as long as you received the Glide distance to offset the fuel burn on the Pulse and you performed the Pulse properly. You COULD NOT USE THE PACK for any acceleration/pulse and YOU MUST send current to the pack during any and all accelerations/pulses to maintain a std. 4 to 5 bars SoC in the Prius II. With the proper timing to avoid the lights, and a perfect P&G technique nailed down including some EV when necessary, you were guaranteed a 110 + mpg segment on that particular route when the temps were above 70 degrees. If I were running the HCH, I would keep my Pulse accelerations just below Pack use. I would need an hour or two to figure out what I would hope to be the best bands on the flats of an Illinois country road but that may differ vs. the hills and road you may be running in your area? I also do not think I would be P&G’ing from 55 - 65 and back either as the acceleration back up to 65 is a fuel sucking monster given you are in a very rough Aero-drag territory vs. a 45 mph top speed in a normal P&G in an HCH.
___I do want to add that when following Dan Kroushl in his Prius II (we were in the chase Prius II) during the last segment of the Marathon Attempt, it was very hard to detect that he was actually cycling through the speed range. The normal ebb and flow of traffic along the stretch of road near Pittsburgh simply fit the P&G style to a T.
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
#9
08-24-2005, 10:38 AM
Re: Pulse and Glide
Hi All:
___Then again, RJ has already come up with a very optimized band and acceleration rate for P&G’ing in the HCH w/ a stick. Maybe he can join this party?
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
___Then again, RJ has already come up with a very optimized band and acceleration rate for P&G’ing in the HCH w/ a stick. Maybe he can join this party?
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
#10
08-24-2005, 11:28 AM
Re: Pulse and Glide
We will see what the 06 Civic has in store because with its EV mode, it may in fact be able to perform a P&G without all the tricks thrown at it?
...from my reading of the limited available info, it sounds as though the ICE valves will shut any time the driver's foot is not applyling pressure to the gas pedal, at any speed, assuming a minimum SoC exists on the pack. This becomes a sort of automatic PnG in that case, although if the engine remains in gear the IMA will be generating and the ICE will still be turning- killing any coast. Hopefully the ICE will remain off when shifted into neutral as it currently does, to kill of regen- then real PnG should be easy?
...from my reading of the limited available info, it sounds as though the ICE valves will shut any time the driver's foot is not applyling pressure to the gas pedal, at any speed, assuming a minimum SoC exists on the pack. This becomes a sort of automatic PnG in that case, although if the engine remains in gear the IMA will be generating and the ICE will still be turning- killing any coast. Hopefully the ICE will remain off when shifted into neutral as it currently does, to kill of regen- then real PnG should be easy?
