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Old 11-15-2011, 02:20 AM   #2 (permalink)
Piwoslaw
aero guerrilla
 
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Join Date: Oct 2008
Location: Warsaw, Poland
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Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
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For each car there is a speed above which P&G doesn't work any more. The better the aero, the higher the speed. Most cars with Cd around 0.30 would probably not be P&Ging at 70mph (if they decided to go that fast), so with your Cd you have to SLOW DOWN to see any results. Improving your aero would help, a partial kammback and a smooth underside would do wonders on that car.

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Originally Posted by JQmile View Post
I semi-slowly accelerated to 70mph or so
Accelerating semi-slowly is only semi-efficient. You accelerate briskly, keeping the engine at ~80% load and rpms around where you have max torque. That's where the BSFC sweetspot usually is.

Quote:
Originally Posted by JQmile View Post
and then would let off till about 50mph, and then speed up. Problem is, my mph would drop like a rock as soon as I let off, and it only took me a few seconds to coast down before I had to accelerate again.
The glide part should be done in neutral. If you just let off the gas pedal then you are engine braking - wasting what momentum you have to keep the engine turning.

Quote:
Originally Posted by JQmile View Post
and it was so light, I had no momentum.
In certain circumstances more weight is better, ie it allows longer glides. But carrying extra weight is more likely to hurt your FE than help, so you should focus on aero and driving style.
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e·co·mod·ding: the art of turning vehicles into what they should be

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[Old] Piwoslaw's Peugeot 307sw modding thread
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