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Old 03-20-2014, 10:06 PM   #3 (permalink)
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Join Date: Feb 2012
Location: Missouri
Posts: 540

Lean and Mean - '98 Honda Civic HX
Team Honda
90 day: 46.69 mpg (US)
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From what I have seen from other EM members, 70-90% engine load is ideal for pulsing. Unless you have your engines BSFC chart its trial and error on what is most effective.

Since you are going to use a vacuum gauge, you will eyeball the 70-90% range from the vacuum reading. 0 inHg vacuum is going to be 100% engine load, which would be WOT. Idle on most cars is ~19-24 inHg on the vacuum gauge, and idle for my Civic is about the same range in actual engine load. So assuming your engine is similar, to achieve the 70-90% engine load you will want the vacuum gauge to read ~5 inHg. Like I said you will need some trial and error over at least a few tanks to see what levels of vacuum on your pulses get you maximum MPG.

Now understand I am no P&G expert, nor do I P&G anymore. But I never bought into the shift point idea of peak torque. For example your motor makes peak torque at 5200 RPM, there is no way revving to 5200 RPM to shift is economical. What I do know is that at a given speed, the lower the RPM the better MPG. The way I drive is basically granny shifting, trying to quickly make it up into top gear. I never go past 2500 RPM before I shift up. I pick the highest gear I can maintain speed (or accelerate) without stalling.
1998 Honda Civic HX - My Project Thread

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