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Hi guys,

I just got my 2nd tank over 70 mpg and I am pretty pleased. I only went a little over 500 miles because the Prius is going in for service today (for steering recall) and I knew they would drop the FE way down while it was there. (I don't know if they leave the car idling or what.) I don't see tanks at 70 mpg after 500 miles very often so I decided to fill it rather than go for my 2nd tank over 700 miles. After 9 or 10 miles the display was at 83.x mpg when I dropped it off, when I get it back I'll see how low they got it (probably 40 something) and I'll try to repair the damage over the next couple of weeks. I took some pictures but they haven't been downloaded yet, I'll post them later. I also posted a 92 mpg round trip segment of 47.8 miles yesterday, I still can't figure out how the supermilers manage over 110 mpg in the Prius, my whole trip was pulse and glide between 33 and 40 mph, I must be doing something wrong but I can't figure out what it is. I've tried pulsing at 25 impg, 30, 35, even 40 when possible although it has been suggested that the pulse rate doesn't matter much. I may try using the battery a little more to extend the glide and maybe expand the range down to 32. During the really high mileage runs (say during the marathon) were the seats, spare tire, etc removed to reduce weight? I am happy to be doing well, but a little frustrated that I can't do better.

Dennis

I still can't figure out how the supermilers manage over 110 mpg in the Prius, my whole trip was pulse and glide between 33 and 40 mph, I must be doing something wrong but I can't figure out what it is. I've tried pulsing at 25 impg, 30, 35, even 40 when possible although it has been suggested that the pulse rate doesn't matter much. I my try using the battery a little more to extend the glide and maybe expand the range down to 32. During the really high mileage runs (say during the marathon) were the seats, spare tire, etc removed to reduce weight? I am happy to be doing well, but a little frustrated that I can't do better.

Dennis

No weight removal that I remember for the marathon. Just careful driving and well timed stop lights. I did some pre marathon runs with Dave and Wayne on separate occasions and we still got over 99.9 with the extra weight. One factor would be the tire pressure and tire wear. I had a new set of OEM tires and wheels that I put on to see what difference they made. IIRC, new OEM tires dropped the FE by about 4 mpg over the old worn out tires. Going from 35 to 60 PSI in the tires helped by 2-3 MPG also. Finally, I had 60k miles on the clock just before the marathon so the mechanicals were thoroughly broken in. 0W-20 Mobil 1 oil might have helped a bit also.

It all adds up.:Banane26:

Hi Dan,

I appreciate the response. I hadn't remembered any mention of weight removal, but I didn't know if maybe that was standard practice. Any other mods like the warm air from the catalytic converter or radiator block? (I had assumed these mods were only used in the late fall to early spring.) My tires are at 58F/56R, I am using Mobil 1 0/20, I am using my original tires (GY Integrities) with 47000 miles on them and they are getting pretty thin. One thought is when I last changed my oil I inadvertently filled it almost to the full mark. Do you think draining a half a quart to put it mid way between the marks would make a big difference? I suppose the simple answer is "try it". At hybridfest what kind of iFE were you aiming for when you would pulse (25-30 impg maybe) and what speed range were you using (maybe 32-40)? Thanks.

Dennis

AZBrandon wrote:
"No modern car dips the crankshaft into the oil sump of your oil pan. They haven't done that with cars since the 1930's or something. Thus oil level has no effect on friction, it's just a measure of how much total oil is in the system to be pumped through the engine. The more oil is in there, the longer it will last before being fully saturated with water and contaminants. You'd have to overfill by a LOT to reach the point where the crank is whipping up the oil."

You may be right, I have read that it is best to aim for about half way between the marks on the dipstick. I recognize however that just because someone typed it into a blog doesn't make it true.

Dennis

Hi Dan,

I appreciate the response. I hadn't remembered any mention of weight removal, but I didn't know if maybe that was standard practice. Any other mods like the warm air from the catalytic converter or radiator block? (I had assumed these mods were only used in the late fall to early spring.) My tires are at 58F/56R, I am using Mobil 1 0/20, I am using my original tires (GY Integrities) with 47000 miles on them and they are getting pretty thin. One thought is when I last changed my oil I inadvertently filled it almost to the full mark. Do you think draining a half a quart to put it mid way between the marks would make a big difference? I suppose the simple answer is "try it". At hybridfest what kind of iFE were you aiming for when you would pulse (25-30 impg maybe) and what speed range were you using (maybe 32-40)? Thanks.

Dennis
I did have a warm air intake but I doubt that it made a difference. I have since removed it because I didn't think it helped. My oil is filled to 1/2 between the dipstick marks, mainly because it lets me get 2 oil changes from 7 quarts. That M1 is expensive but I go 12k miles between changes.

I honestly wasn't looking at the iFCD during accelerating but if I had to guess it would be around 25 MPG accel rate. The key is to let off the accelerator fully then gently back on to kill the ICE. It took 48 mins to go 20 miles to that comes out to 25 MPH ave with 41 MPH max speeds down the hills. The other two 99.9's at HF took longer so I was the speedster of the group.:D

Depends somewhat on your terrain, too. I managed a vaguely close
second to the three guys that maxed their meters at Hybridfest,
bringing in 99.2 for that run, and then only 94.something a week
later at the Ipswich thing -- same driving technique, but more
hills and weird turns. Also after I finished the Ipswich run
and force-charged the battery back up it was down to 84.something,
so that's probably more like the real-life MPG I was really holding.
That's my argument for why 20 miles is way too short to prove
these things out. In other more real-life backroads driving
around here I'm lucky to hold high 70s over a longish haul, and
then we add cold starts, short trips, and other aspects of real
life back in and there we are back down in the 60s. But still
bustin' the EPA numbers, heh.
.
_H*