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Old 09-25-2014, 10:22 PM   #208 (permalink)
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Join Date: Jul 2012
Location: Northern, NY
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Centurion - '74 FIAT X1/9 Centurion Full Race DNA
Last 3: 143.5 mpg (US)
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Originally Posted by sendler View Post
One tank competition results with a small top off are prone to fill errors and thermal expansion and don't reflect real driving. Multiple, back to back fill up logs are the only way to see what a vehicle really gets.
Ladies and Gentlemen of the J-J-J-J-Jury.....

Looking back at the postings in this thread let's look at a few items of interest and see how they fit-in with this most interesting drive-by statement above....

#1) I drove roughly 231 miles south to the hotel in Horseheads. The start of the trip was on secondary roads and then down I-81 and eventually though a couple of towns in-stop-n-go traffic. Also, it was really, really, windy that day. The weather channel reported 40mph winds and these were mostly (but not all) met head-on. When I arrived in the hotel parking lot I still had plenty of fuel in my two-gallon tank but the fill-up for Stage 1 wasn't until the following morning. What is the relevance of this? Well it would appear that leg #1 of my journey was in REAL driving conditions and fill up #1 was about to happen the following morning (probably when it was cooler out too...) So much for the thermal expansion theory on that fill-up...

#2) The fill-up at Valero in the morning was my first fill up for the entire event and took all of about 30 seconds. At the pump using only the 231 mile figure to the hotel, (plus the REAL drive to Valero that I didn't even figure in because the fuel officials had me reset my odometer at that time so I could only use the written down mileage from Colton to the hotel) and the pump reading of 1.34 gallons gave me my first reported mpg of leg #1. It was 172mpg...

#3) Stage 1 ... Having been to the Green Grand Prix Sendler, I suspect you remember that really steep hill up that goes all the way up to the track. It is impressive and about as REAL as any hill I've ever been up. And keep in mind, that "hill" that goes all the way up to the racetrack is part of the Stage 1 mpg figures. Most people in normal driving are not likely to encounter a hill of that magnitude, at least not up here in the Adirondacks.

In addition, this thread has many screenshots of the actual event when on the Watkins Glen track. Using those images and video, plus any aerial and/or elevation maps of the track, I invite anyone to to please illustrate how the track is somehow different than typical geography encountered while driving... I mean - wow.....

Anyway, Stage 1 isn't a 5 minute romp across the boardwalk; It's over 100 miles and roughly 2.5 hours on that gorgeous track - but somehow - that's not REAL driving...(no corners, no hills, no traffic, no mandatory pitstop to break your stride and certainly no speed limits, oh well you get the idea...)

After the track is lunch. Yes, the cars stay at the track (in the garage area) for a period of time and probably lose much of the "thermal expansion" they generated during the laps... Following that was my extended trip back down to the pump.. Extended because I went the wrong way as did others (screenshots from the in-car dvr validate this).. So finally at the conclusion of the cool rain/mist filled drive to the Valero, we have fill up #2 of my trip. And that was... well....record breaking... and 200+ mpg is an accurate statement. For this discussion I'm fine with just the 200mpg though (at this point - it's just easier...)

#4) Having just filled up I was now ready to get sick and vomit all over Watkins Glen (which I did). With no relief in sight after an hour, I decided to head home on my full 2-gallon tank of fuel. Because I felt like death warmed over, I took an alternate route home. Due north to I-90, then east to Syracuse, and then North up I-81. The last 1.5 hours of the trip are on secondary roads.. The conditions were without the horrible headwind encountered on the way down, it was significantly hotter, and I drove Centurion nearly at the 3000 rpm limit to get home sooner so I could die in peace.. But, I guess none of this represented any REAL driving either.. There were 2 stops and one was to confirm a phone call with Sheepdog 44, about the awards results. The second was an attempt to eat - that was a waste of money.. Anyway, I got home and crashed big time. Centurion would have to wait until morning to get a the 2-gallon tank filled one last time.. But then that would mean it would lose it's thermal expansion from the trip home.!! Geez! What are the chances? That morning's fill resulted in just over 190mpg...

So, a quick recap:
Three distinct back-to-back legs of the journey:
--231+ miles down
--100 plus miles for Stage 1
--250+ miles on the return trip

Three distinct back-to-back "non-thermal expansion retaining" - fill ups:
---200+ mpg
---190 and a whisker mpg

If anyone there has ever watched "My Cousin Vinny", you'll understand at this stage, how I can relate to Vinny!

The defense rests....



Last edited by changzuki; 08-03-2018 at 11:07 PM..
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