No aero mods, just drafting

[So_SiMpLe_]

Hi there!

Some days ago I made about 30 miles at 90km/h, 55mph, behind a truck and it was just impressive, I've never tried it.

My maximum average on that road was 3.5l/100km, but behind the truck I made 3.2l/100km, with no aero mods at all. Just have over inflated tyres.

As you can see here:



I'd imagine if the car had an inferior Cd....

[SVOboy]

I'm sure some more people will chime in here, but before you get too intoxicated with the notion of drafting, remember that it's probably one of the most dangerous things you can do on the highway and your life isn't worth a bit of fuel economy

[justjohn]

Depends on how close you draft. If you're paying attention you can get close enough for some mild benefit quite safely.

[So_SiMpLe_]

Yes mate I was keeping a safe distance, abou 8 to 10 mters, of course it is no worth a bit of fuel economy, that I totally agree with you.

Some threads here talk about the 2004 SEAT ibiza Cupra intake wich lets the car breath a bit better thus reducing a bit the fuel consumption.

Once that intake costs about 60€ it won't be payd any soon, so I guess I'll make one with the same diameter.

Wanna keep the fuel consumption to the minimum.

[Bill in Houston]

I had a rental GM minivan one time that was shaped like a brick. I could see a drafting benefit off of ANYTHING in that van. Like a Suburban 3 seconds ahead would still show measureable benefit.

Sooo, is 3.2 good?

[euromodder]

Originally Posted by So_SiMpLe_

Yes mate I was keeping a safe distance, abou 8 to 10 mters,

8 to 10 meter hardly qualifies as a safe distance.

[Joenavy85]

8 to 10 car lengths maybe, i usually stay back about 4 seconds behind regular traffic, and about 3 seconds behind Semi-Trucks

[pnambic]

Some newer cars have cruise control with sensors to maintain a set distance behind the vehicle in front of you. I wonder what their operating limits are, both high and low, distance-wise.

Btw, an interesting (ok maybe not terribly interesting) read...
www.visualexpert.com/Resources/reactiontime.html


It mentions that when traveling at 55mph, you're covering 80 ft/second.
They suggest a time of 1.5 seconds to recognize, react to and then begin to brake for a given stimulus. If it takes a person 1.5 seconds to react to the brake lights of the vehicle in front of them, then they've traveled more than 120 ft, which at 40 meters is a good deal further than the 8 to 10 meters mentioned above.

Now, I like to think that I'm faster than that, but even if my reaction time is only half a second, I've still lost 13 meters before I can hit the brake.

[Joenavy85]

factor in braking distance for the vehicle and you see how long it really takes to stop. i'm sure the 1.5 seconds is an average, obviously those of us that are vigilant while driving will be faster, but the average numb nut out there isn't as "in tune" to what the heck he's doing most of the time and will therefore take longer to react

[So_SiMpLe_]

Ok guy sorry, I was doing it responsibly, at one average car distance maybe.

Just was trying to show the effects of dragting a truck.