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Old 01-23-2015, 10:49 AM   #263 (permalink)
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tough, a little bit, for any hope of accuracy you would have to do some coastdown tests and have you and your vehicle weighed with a consistent fuel load (and tire psi) and warmup to determine CDA and CRR. Plus you want consistent atmospheric conditions.

HP to the wheels would be a function of drag at speed and change in velocity.

Fuel consumption would be monitored by an injector (or other accurate source).

Speed is the VSS signal (or rpm if using different gears).

Map is indicitive of load.

So you log fuel rate, speed, map. Accelerate at different map values using your foot and determine the hp required (and fuel consumed)between steps as you accelerate. Build the bsfc chart row by row by keeping map consistent during each run (As practical).

Standard testing, run in both directions and average, repeat. Flat test area with no wind is best.

Last edited by P-hack; 01-23-2015 at 11:29 AM..
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