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Old 10-16-2010, 08:48 PM   #5 (permalink)
The Atomic Ass
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Location: Mason, OH
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Priinocchio - '17 Toyota Prius Two Eco
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Originally Posted by 4ringcircus View Post
Thanks Old Mechanic. I did some errands this morning and find that no matter what gear I am in, if I plan on accelerating and the engine is less than 2200 rpm, I should down shift one or two gears and let the engine scream up to 4000k.

For example, I have always assumed it was most efficient to accelerate with light throttle and shift to maintain a 1200 to 2000 rpm range. When doing this however, the vacuum immediately falls as low as 1 inch. The only way to accelerate and keep it above 1.5 inches is to wind first gear to 3700 rpm then skip to 3rd or 4th gear and maintain speed.

This is the opposite of the old dummy upshift arrow lights; seems completely counter-intuitive. Is this the definition of Power and Glide?
I'm assuming you've got the I4? My father has the S-10 in my profile, and it will pull from idle in top gear. Not very fast, but it'll pull it. It seems to stop lugging at any throttle position around 1800 RPM, so that's about where we floor it if we're getting on the highway. Letting the revs fly up is the only way to get better acceleration out of the engine, true, but that is going to hurt fuel economy, no two ways about it.

I am of the opinion that you just do not use a vacuum gauge for acceleration. That it is for steady-state cruise to show you how steady your right foot is.

Pulse and glide involves brief periods of maximum acceleration at the lowest RPM's that won't lug the engine, followed by coasting, often with the engine off throughout the coast.
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