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California98Civic · 07-29-2011, 11:01 AM

Actually the test was B-A-B-A if A is always supposed to be an “unmodded” run.

PURPOSE
To see if I can do a standard P&G technique I call “GLEN” (Glide, Load, Engine-on, Neutral) on the freeway for significant FE benefits, preferably convincingly beyond possible “noise” of 1-3%. I have a 5.7 mile uphill freeway leg on my regular commute that I cannot route around with practicality or with sufficiently beneficial FE effects to justify the extra distances. Typically, I have scored low/mid 40s on this stretch by driving slower than is legal. Even then, this leg still brings down my averages. If I had a good solution, I could bring my averages up and not risk a ticket for too slow driving.

METHOD
Simple. Same time of day with roughly similar temps day-by-day over a one week period. Wind quite regular (absent) day to day. Drive one day with hypermiling, then the next day without, repeat until I have six runs minimum. The P&G technique used an acceleration arc from 55mph-65mph at 80% load. I then coast down to 55 again, seeking a 60mph average speed during the run. Up the steepest hills, I ranged from 55-60mph in the acceleration arc seeking a 57.5mph average. When doing the straight driving runs, I did my best to hold a steady 60mph, which was very tough in hilly terrain. Climbing the steepest hills I reduced speed to about 57.5. I never used EOC or any other hypermile method, such as driving in the slip-stream.

RESULTS
“A” = with P&G and “B” = without P&G
A – 51.2mpg; ave 59.8mph.*
B – 45.0mpg; 58.8 ave mph.
A – 54.9mpg; ave 57.1mph.
B – 47.7mpg; 58.1mph.
A – 54.5mpg; 59.0mph.
B – 44.9mpg; 58.9mph.
*I forgot the exact mph number at the close of the run but this is close to correct.

“A” averages = 53.53mpg @ 58.63mph
“B” averages = 45.87mpg @ 58.60mph

“A” is 7.66mpg HIGHER than “B” or 14.31% better.

Random confirmation is suggested possibly by a 22 mile run I took the other day on the freeway, using this GLEN P&G method. I got 63.4mpg at nearly 60mph. Under normal conditions a month ago I could have seen maybe 52mpg on that run. Maybe only 49.

07-29-2011, 11:01 AM	#1 (permalink)
California98Civic Cyborg ECU Join Date: Mar 2011 Location: Coastal Southern California Posts: 6,299 Black and Green - '98 Honda Civic DX Coupe Team Honda 90 day: 66.42 mpg (US) Black and Red - '00 Nashbar Custom built eBike 90 day: 3671.43 mpg (US) Thanks: 2,373 Thanked 2,172 Times in 1,469 Posts	P&G freeway tested ABAB +14% FE Actually the test was B-A-B-A if A is always supposed to be an “unmodded” run. PURPOSE To see if I can do a standard P&G technique I call “GLEN” (Glide, Load, Engine-on, Neutral) on the freeway for significant FE benefits, preferably convincingly beyond possible “noise” of 1-3%. I have a 5.7 mile uphill freeway leg on my regular commute that I cannot route around with practicality or with sufficiently beneficial FE effects to justify the extra distances. Typically, I have scored low/mid 40s on this stretch by driving slower than is legal. Even then, this leg still brings down my averages. If I had a good solution, I could bring my averages up and not risk a ticket for too slow driving. METHOD Simple. Same time of day with roughly similar temps day-by-day over a one week period. Wind quite regular (absent) day to day. Drive one day with hypermiling, then the next day without, repeat until I have six runs minimum. The P&G technique used an acceleration arc from 55mph-65mph at 80% load. I then coast down to 55 again, seeking a 60mph average speed during the run. Up the steepest hills, I ranged from 55-60mph in the acceleration arc seeking a 57.5mph average. When doing the straight driving runs, I did my best to hold a steady 60mph, which was very tough in hilly terrain. Climbing the steepest hills I reduced speed to about 57.5. I never used EOC or any other hypermile method, such as driving in the slip-stream. RESULTS “A” = with P&G and “B” = without P&G A – 51.2mpg; ave 59.8mph.* B – 45.0mpg; 58.8 ave mph. A – 54.9mpg; ave 57.1mph. B – 47.7mpg; 58.1mph. A – 54.5mpg; 59.0mph. B – 44.9mpg; 58.9mph. I forgot the exact mph number at the close of the run but this is close to correct. “A” averages = 53.53mpg @ 58.63mph “B” averages = 45.87mpg @ 58.60mph “A” is 7.66mpg HIGHER than “B” or 14.31% better. Random confirmation is suggested possibly by a 22 mile run I took the other day on the freeway, using this GLEN P&G method. I got 63.4mpg at nearly 60mph. Under normal conditions a month ago I could have seen maybe 52mpg on that run. Maybe only 49. __________________ See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green* over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread. Last edited by California98Civic; 07-30-2011 at 11:06 PM..