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Old 09-27-2011, 12:55 AM   #21 (permalink)
California98Civic
Cyborg ECU
 
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Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
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Quote:
Originally Posted by The Verge View Post
California98Civic, I am new at this so what is a BSFC map? Is bump starting using the clutch in 5th gear to restart after a EOC cycle? During pulse is it better to get back up to speed quickly or better try to get good MPG while accelerating?
Here is a link that will help with the basics of what the map is. You are looking for the "sweet spot" on an island graph much like this one, with different values specific to your car. The pulse is counter intuitive because you are not trying to drive slowly for good instant MPG numbers. Instead you are quickly accelerating in order to achieve engine load that puts you in the sweet spot of the BSFC map. You burn what you burn more efficiently over a more brief period of time... then you shut off the engine when you reach desired speed and coast, key in the run position, all power on, but engine off. What gear you choose for the bump start varies with your speed. Most drivers here that I have seen offer advice have suggested bumping in a gear two above where you intend to drive. If 3 is the appropriate gear at a given RPM, bump in 5. And if 2, bump in 4. I bump start as low as fifteen RPMs frequently, very lightly friction spinning the engine. Then I engage the appropriate gear normally. You can hardly tell I have cut or restarted the engine most of the time. But it takes practice. Your power brakes will keep vacuum in them after you cut the engine, but only for a couple good pumps or so... keep an eye on brake power and don't EOC in potentially dangerous spots/situations.

I hope that helps... be safe...

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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.



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