Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Buddy just got a Dyno that measures BSFC!

jime57 · 04-13-2009, 07:37 AM

A BSFC "curve" is different from the BSFC "contours that most folks are thinking of and which are shown in the above ref. Problem is that there are two values of BSFC for each engine RPM, over some portions of the RPM/torque curve. It would require the acquisition of considerably more engine data to map out the contour map. That would involve running the engine much longer. A single full power pull traces a pattern across a portion of the BSFC contour.

But, I don't really know the answer of certain. It will be nice to see.

As Wayne Gertes over on CleanMPG recently pointed out, BSFC curves aren't really all that valuable for solving the question of optimum RPM in fuel economy terms. The problem being that the BSFC data is for full throttle and that is virtually never the situation when one is attempting to find the best fuel economy. It is valueable for NASCAR racer and others who operate their engines at full throttle for considerable times.

Anxiously looking forward to your first data.

04-13-2009, 07:37 AM	#4 (permalink)
jime57 Master EcoModder Join Date: Oct 2008 Location: Mid-Atlantic Posts: 491 OurInsight - '06 Honda Insight Thanks: 170 Thanked 69 Times in 44 Posts	A BSFC "curve" is different from the BSFC "contours that most folks are thinking of and which are shown in the above ref. Problem is that there are two values of BSFC for each engine RPM, over some portions of the RPM/torque curve. It would require the acquisition of considerably more engine data to map out the contour map. That would involve running the engine much longer. A single full power pull traces a pattern across a portion of the BSFC contour. But, I don't really know the answer of certain. It will be nice to see. As Wayne Gertes over on CleanMPG recently pointed out, BSFC curves aren't really all that valuable for solving the question of optimum RPM in fuel economy terms. The problem being that the BSFC data is for full throttle and that is virtually never the situation when one is attempting to find the best fuel economy. It is valueable for NASCAR racer and others who operate their engines at full throttle for considerable times. Anxiously looking forward to your first data. Last edited by jime57; 04-13-2009 at 07:42 AM..