Useless Information

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DougAMiller

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Love this kind of stuff Doug! But the math is all greek to me. I have run 2-way averages from 35 mph on up to 80. 35 mph sees the truck in 5th gear and for the most part the mileage is the same as at 40 when in 6th. There was one test where this was different, running E85 @ 71% alcohol content, the truck got 15 mpg @ 35 mph and 18 mpg @ 40 mph.

Have yet to complete my E30 tests.

What's the c/d of the Trans Am? I think our trucks is .363 which is even better than my daughter's little Kia which is .38!
The 3rd gen Trans Am was 0.29, by comparison the GMT800 Tahoe is 0.39. A GMT900 hybrid is 0.34. However, the frontal area of the Tahoe is double that of the TA.
 
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swathdiver

swathdiver

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The 3rd gen Trans Am was 0.29, by comparison the GMT800 Tahoe is 0.39. A GMT900 hybrid is 0.34. However, the frontal area of the Tahoe is double that of the TA.

I remember my '79 Buick Regal's c/d was .443 and then they streamlined the models from '81 on and got down to .434 or .41, can't remember! Woohoo!

I'll have to look at your chart in detail more later on to see if I can understand it better. Would love to run the math against my observations and see if there is room for improvement. Fun stuff.
 
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swathdiver

swathdiver

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Got home a few minutes ago and went back out to the truck and caught her in afterblow mode, both front and rear fans turning low to dry out the condensers. Cool.
 
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swathdiver

swathdiver

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My wife and I have another daughter graduating from high school soon and my health has improved to where I've been able to begin working again out of the house. Signed up for Uber and have been using the truck for it. Just filled the truck with its 18th consecutive tank of E30 since January. Average mpg this whole time is over 15 mpg! My average Ubering is over 16 mpg.

Despite that, somehow my lovely wife still manages to get 11 mpg and my best tank Ubering was almost 20!

Spoke with the gas station owner and the E15 and E30 are blended on site. This probably explains why there is no consistency in the alcohol percentage. It's not supposed to be below 25% by law but this motor delivers its best fuel efficiency between 18% and 22% and no knock/pinging at WOT.

Was getting worried this morning, light came on while still thirty plus miles away from gas station and still had passengers to drop off. The light was on for over an hour but kept displaying the range in the mid 50s depending on speed. Finally got up there and expected to pump in 28+ gallons but she only took 26.4 which is the usual for filling up right after the light comes on. Went 404 miles which is also a record distance since I started keeping records. 16.29 mpg and 1.85 GPH and 13.36 hours between refuelings.

ACDelco has a new oil out for all aluminum LS motors. Specs look better than Mobil One. Tried to buy 4 gallons but there's a 12 gallon/case minimum so I'm setting aside a few hundred now to buy 40-50K miles worth of oil changes. Will report on that after the second change and the sample comes back from Blackstone Labs.

AC Compressor Clutch has gotten loud but is consistent. I'd like to change it since ACDelco makes a kit without having to go into the whole system but not sure I could physically do it on the car and don't know who I can trust around here to work on my car.
 
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swathdiver

swathdiver

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Since the recording of data began and the production of statistics I've always had a discrepancy between fuel pumped and fuel used. Now I'm pretty sure it's been figured out.

The truck has been running 3 separate fuels since October 2017. Each fuel has an almost exact 8% difference between pumped and used. After running the numbers, it has to be that the remote starts do not figure into the DIC numbers. 8% difference between all fuel types and 1.6 GPH which would make sense as the motor runs rich to get up to temp quickly. 99% of my starts are via the remote start feature and by the time we board the truck, it's either about to shut off, just shut off or has been restarted.

upload_2019-6-1_5-15-29.png

Well, GPH is not accurate, it's the result of dividing the difference into the number of tanks, it's the average amount of fuel "lost" per tank which would mean it's the average amount of fuel used during remote starts for each tank of gas. So that's $4.11, $3.61 and $5.31 per tank to do remote starts.
 
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