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My family is planning a trip to Philadelphia, starting somewhere between 12am and 2am. I don't remember the geography of the route very well, but I'm pretty sure the section between here and Columbus is basically all flat. (Hopefully someone else here knows what the rest [besides the alleghenies] is like) The question is, if I don't know the terrain and can't see it very clearly is there a high probability of hurting my mileage by p+g'ing? i.e. is it worth it to try it if I don't have an sg to check the results? The speeds in question are 55-70 vs a constant 62-63.

I wouldn't try to P&G without a SG in any situation. There is a good chance you will hurt your FE.

My family is planning a trip to Philadelphia, starting somewhere between 12am and 2am. I don't remember the geography of the route very well, but I'm pretty sure the section between here and Columbus is basically all flat. (Hopefully someone else here knows what the rest [besides the alleghenies] is like) The question is, if I don't know the terrain and can't see it very clearly is there a high probability of hurting my mileage by p+g'ing? i.e. is it worth it to try it if I don't have an sg to check the results? The speeds in question are 55-70 vs a constant 62-63.

I do that run about three or four times a year.

Is your car a manual? If so then you should have no problem with P+G. Cincinnati to Columbus is flat as a pancake. C-bus east on I-70 is flat for about 30-40 miles and then rolling hills all the way to Wheeling--excellent opportunity to Fas downhill. Take I-70 through Wheeling, don't take the bypass--that mountain will murder your FE. Then I-70 to New Stanton (55MPH speed limit) and then the turnpike on into Philly. There's a huge Fas opportunity (at least 5 miles) as you approach Sideling Hill right after Breezewood which should be no problem if your tires are pressed up properly. After the mountains it's low rolling hills all the way into Philly. I pulse to 55-60 at the top of a hill and then glide down the grade which usually isn't enough by itself though (doing 50 at the bottom?)

I get about 55 MPG going there and 50 returning (with E10 RFG in the fuel tank).

Avoid filling up at the Sunoco's on the turnpike if you can--they're all E10 and I've seen some really butt-ugly MPG's with their $hit in my car.

I hope that helps? I just do 50-55 in the right lane the whole way and it takes ~10-11 hours.

My family is planning a trip to Philadelphia, starting somewhere between 12am and 2am. I don't remember the geography of the route very well, but I'm pretty sure the section between here and Columbus is basically all flat. (Hopefully someone else here knows what the rest [besides the alleghenies] is like) The question is, if I don't know the terrain and can't see it very clearly is there a high probability of hurting my mileage by p+g'ing? i.e. is it worth it to try it if I don't have an sg to check the results? The speeds in question are 55-70 vs a constant 62-63.

Be careful with your battery charge state. I ran my battery down at night by doing FAS P&G before getting the SG. Also, 70 is a bit high for good FE.

Larry

As for FASing, our camry is an automatic so the closest I can do is NICE-on. And even if it was a towable, If my mom spotted me turning the key I doubt I'd be driving for much longer. And the speed in question is to keep the driving time to 9 hours (n/i stops), which is about the most my family will take before taking a plane (of which the total trip time is ~8 hours because of connections in Chicago or something). Anyways given the fact that I can't FAS, would it be better to glide (generally lose speed) or DWL (gain speed) on downhills?

Hi Degnaw:

___Until you are ScanGauge equipped, don't bother. As Pill said, you will more than likely receive lower FE and will probably find your 12V unable to bring the ICE back online while you are forced to glide to a stop from 50 + mph somewhere in the middle of nowhere. You simply have to watch your 12V and know what you are both doing and pulling before jumping on a P&G highway scenario.

___Good Luck

___Wayne

Doing ICE on P&G without a scan gauage is do able. Althought I would do 55-65 instead of 55-70. However being so new, you might be better off sticking with easier techniques to start with. Air the tires up to the correct pressure, and drive slower. Maintain a large distance between you and the next car, accelerate as slow as you can safely accelerate, and try to not stomp on the break too much.

Make sure you dwl up hill. I like to glide down hill in neutral. Howerver I would also be surprised if you mom was cool with you shifting into neutral.

Make sure you dwl up hill. I like to glide down hill in neutral.

Outside the alleghenies (where the backside of the hills are steep enough to gain speed while gliding), how would I maintain speed? Should I shift back to drive before the downhill ends, and accelerate quickly so I can lose speed on the uphill? Or should I just gain some of it back, and maintain that speed on the uphill?

My tires are either 44 (gas station gauge) or 50 psi (stick-gauge), and I haven't exceeded 65mph in months.

We're leaving in two days, so basically considering the inability to FAS or track my mileage, would it be better to, in rolling-hill areas, DWL (gain speed downhill, lose speed uphill), or P+G (gain speed uphill, lose speed downhill). Or is there some special point at which you start pulsing or stop gliding while p+g'ing, that's not at an uphill-downhill transition?

At highway speed, the difference between Nice-on and FAS is minimal. Consider that 60mph divided by 0.3 gph gives you 200mpg. There's not a lot of difference between 1/200th gal/mile and zero gal/mile.

I know the difference is minimal, but it adds up to maybe half a gallon over the course of the trip, which could mean the difference between "you'll probably get better mileage by p+g'ing" and "you'll probably hurt your mileage by p+g'ing", without a scangauge.

So in pulsing and gliding in hilly areas, do you pulse over the entirety of the uphill, pulse at the bottom of the downhill and dwl uphill, dwl uphill and pulse at the top of the next downhill, or any of the two former scenarios while maintaining a constant speed uphill? If the answer to the question in the first paragraph is "probably hurt", ignore this question.

I probably could decrease the top speed to 65-i'd just have to cut out 20 minutes (not that much) worth of stops.

I like to start the pulse just before the bottom, or right at the bottom, but definitely before I'm pointing uphill.

I pulse uphill at whatever power level matches the hill. The goal is to reach peak speed just before the crest, gliding up and over. For a longer hill, I'll use lower power; for a short hill, more power. What I don't want to do is get up to speed early on a long hill, and then be maintaining at higher rpm the rest of the way up.

I choose the bottom of the P&G speed range, at the bottom of the hill, so I have enough power for the next uphill. That's about 45mph for me and my hills. I don't want to be laboring up the hill at full power gaining 1/2 an mph at a time. Better to start the pulse sooner, at the end of the downhill, than to labor up the hill.

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Edit: You're driving the camry auto? I'd go with DWL in that case. I'd apply my notes above to a manual transmission.

Thanks for the tips - it makes me sick to think about the gas wasted on the last trip we took, driving between 70 and 80 with 20psi tires. We didn't measure our gas mileage then and I'm somewhat glad, because it's probably about 20mpg. I'm hoping I'll be able to measure it on this trip, though-my goal is 38mpg (new epa 31) but the speed requirement might make that harder.

Sorry about bumping this thread again, especially with a weird question like this:

Anyways, there's supposed to be a 4-6mph sidewind between Cincy and Columbus; would distant drafting (assuming i can find a truck at 2am) be a waste of effort since 5mph means 14 feet in 2 seconds, or does the truck slow the sidewind down somehow? Should I stay in the left lane whenever possible to try to gain some benefit from the guardrail/trees if there are any?

I never use the left lane except when someone in the right lane is riding my bumper and wont change lanes, but as soon as he is gone by I move right. the left lane is the passing lane.

Technically, you're right. The draft would be better in the other lane. But I think the "rules of the road" trump that, so I'd stay in the right lane. 4-6mph isn't much, anyway. 20mph is another story.

Hey Pale Malenesian, this brought up a question...I fas my manual trans all the way to work with flat terrain. My engine is off practically more than it's on as I p&g. I've been getting up to 64mpg on my returns and about 58mpg going to work.

Do you think all the fasing is worth the trouble or would nice-on p&g about the same? Thanks in advance. Man, Pale you are getting insane numbers great work....

Do you think all the fasing is worth the trouble or would nice-on p&g about the same?

Obviously I'm not an expert, but I think your speed during the glide is the biggest factor in how much relative effect fas has - At 60mph Nice on would be getting 200mpg, but at 20mph it's only 67mpg. Someone who knows what he/she's talking about should weigh in though.

Well said. That is a valid point. At 20mph, FAS is a huge improvement, while at highway speed, it's not so much. Still, it's worth it on the highway for that little bit more.

As to my numbers, well, like you said right there: My engine is off more than it is on. To me, in my quest for even more, it's worth it. If you're already doing P&G, it's really not a lot more to do. Try both ways and see the numbers and decide for yourself.

Well said. That is a valid point. At 20mph, FAS is a huge improvement, while at highway speed, it's not so much. Still, it's worth it on the highway for that little bit more.

As to my numbers, well, like you said right there: My engine is off more than it is on. To me, in my quest for even more, it's worth it. If you're already doing P&G, it's really not a lot more to do. Try both ways and see the numbers and decide for yourself.

Pulse and glide nice on vs FAS works better on cars/trucks/suvs that has a higher gph.

I'm back, and I was able to calculate the mileage on the highway parts at least. On the way to, with regular gas, we filled up 10.275 gallons after 446.2 miles (110 of which my mom drove), which is 43.43mpg. On the way back I drove all 560.5 miles on 12.409gal (of E10), which is 45.37mpg if I'm not mistaken. And that was considering I dwl'd philly-wheeling 60-70mph, and 2-3s drafted a truck the rest of the way at 65~ mph :confused:. The transmission puts the car at only 2200 rpm at 70mph, but the mpg figures were still dubiously high considering I rarely dropped below 60 (though I did go as low as 45 twice to keep the car in 5th gear).

edit: I forgot to note that our GPS read our speed at ~4mph lower than our speedometer read it, hence the higher (speedometer) speeds. 66mph is still pretty fast for FE though.

I also floored the gas pedal once when I was trying to merge onto the highway before Wheeling-I was accelerating from a stop sign after breakfast (if you're not familiar with the area, there's stop signs to merge onto the interstate) and was at 30mph when a semi comes barreling down the corner behind me at probably 70mph. The transmission didn't shift until 5000rpm :eek: (redline 6500). Actually, now I'm curious how much fuel that actually wastes - even if its 1mpg during the acceleration, the shorter distance of the acceleration should counteract that to some degree right?