View Single Post
Old 09-26-2014, 10:24 PM   #213 (permalink)
Changfa diesel + Suzuki
changzuki's Avatar
Join Date: Jul 2012
Location: Northern, NY
Posts: 527

Centurion - '74 FIAT X1/9 Centurion Full Race DNA
Last 3: 143.5 mpg (US)
Thanks: 160
Thanked 463 Times in 235 Posts
Originally Posted by sendler View Post
Was that so hard? A fuel log with numbers like that would be very impressive and easy for visitors to see at a glance. And the average will post right under your signature.
Please don't be confused by the mpg numbers roughly five posts ago with an actual fuel log...I posted these numbers in one place on your behalf because you seemed quite confused, and maybe even doubtful, by the Green Grand Prix figures thus envoking the following response after I stated exactly why I didn't use a fuel log:
Originally Posted by sendler:
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.

Then 8 minutes after I posted my back-to-back trip distances/details, you still seemed even more confused by applying an incorrect/fabricated scenario as to how Centurion pulled its mpg figures. In your words :
Originally Posted by sendler:
Everyone here would agree that the best way to tell what economy a vehicle gets is by logging several back to back tanks. Your tank is small so the thermal expansion errors will be less but they can be substantial in competition for something like an Insight with a 11 gallon tank and such a small amount needed to top off. It works like this. You show up to the competition which starts early in the morning, empty or with a cold, overnight tank. Fill the tank to the brim with fuel out of the ground which is at 10*C. Go to the track and drive your 130 miles. All the while the fuel is flowing to the hot engine area and back to the tank through the return line. You go back to the station to fill up again except you have used 1 gallon out of the tank and now it is at 30*C. That 10 gallons that should be left now measures 10.2 due to the thermal expansion of gas at 1% per 10*C. So the consumption is measured at .8 gallon instead of 1.0. The 130 mpg just became 162.5

Just wanted to clarify that what I posted was simply a response to help you with your postings - is not a fuel log.




Last edited by changzuki; 08-04-2018 at 12:05 AM..
  Reply With Quote