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Old 07-08-2011, 04:12 PM   #16 (permalink)
The PRC.
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Originally Posted by endurance View Post
That's definitely the sweet spot for me. I'm completely comfortable in the 75-100' range and you can hear and feel the difference in air flow over the car. You can watch the LOD drop and the MPG climb as soon as you crawl into the slipstream. I had a 77 mile stretch behind a semi once that averaged 48.8mpg at an average of 69mph. That included some bits over 80mph and some city-highway traffic around 60mph.

You don't have to get into the stupid-zone to get great mpg gains. All you need to do is enter into the disrupted airflow and low pressure zone and you make impressive gains.
Yep, I think slipstreaming is dumb because of the danger of emergency stops of debris from the vehicle in front's tyres. Keeping to the "2 second rule" (pick a point at the side of the road, count 2 seconds from when the vehicle in front passes it until you do. Less than 2 seconds you are too close) still means gains in my experience - the air vents go quiet and you can ease off the throttle with no loss of speed.

If someone fills the gap then that is usually because they are lane changing to exit or enter a motorway. My attitude is let them do this, it means you concentrate on them whilst they concentrate of getting to the outside lane asap and may not be watching you. And it means people can merge on/off without you braking.
[I]So long and thanks for all the fish.[/I]
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