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Old 02-26-2018   #1
Paul Workman
 
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Join Date: Nov 2007
Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri
Posts: 6,466
Default Nitro Methane vs. John Force in AZ

Look at the raw nitro pouring out of the front, right header...NOT GOOD!

https://www.youtube.com/watch?v=SsO6yXCiwoo

"Stoich" for NM is 1.7:1 (AFR).

http://www.smokemup.com/tech/fuels.php

An interesting NHRA article explained: A liquid is NOT compressible. And, due to the high volume of liquid nitro, it fills a good portion of the combustion chamber on the compression stroke. So, if the fuel fails to be ignited, the plugs get fouled, and there is more than a good chance all of the liquid will NOT be evacuated fully. Then, the next charge is simply added to whatever was left - further shrinking chamber compression area and so on causing the cylinder to practically become hydro-locked! KABLOOIE!

Note: This is the main reason TOP FUEL engines use dual MAGNETOS and twin spark plugs for each cylinder: make dang sure that nitro burns and leaves the cylinder clear for the next huge shot of liquid nitro. Shortly after leaving the starting line, the engine begins to "diesel", but up to then the ignition reliability is especially critical to avoid catastrophe.

Last edited by Paul Workman; 02-27-2018 at 08:55 AM.
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