Drafting to increase MPG... works. 24mpg steady.
#1
Drafting to increase MPG... works. 24mpg steady.
I've been doing a TON of highway travel lately (I'm talking in excess of how far our fuel tank can take us), and I've been using my ScangaugeII Religiously to help me check MPG data.
It shows you realtime, and you can of course reset a 'trip' calculator to show your mpg.
I find that with cruise control active, on average, it gets 19-21mpg on its own, cruising somewhere between 60-70mph.
However, the second I get behind a big truck, and he's at least 4 car lengths infront of me, it goes up a good 1.5mpg easily.
If I get even closer, say two car lengths, (A bit closer than preferred for safety, but doable), The RX-8 sits at 24mpg indefinitely.
I've made long trips with the RX-8, with mostly drafting, and only using cruise control adjustments in 6th grear, and I've gotten 24mpg straight for the whole tank. "decent" fuel economy is possible, if not practical.
I've clocked 320mi on the odometer before having to fill up, and I think that is fantastic. There should be another gallon in the tank at that rate as well, but I'd rather play safe than sorry.
It shows you realtime, and you can of course reset a 'trip' calculator to show your mpg.
I find that with cruise control active, on average, it gets 19-21mpg on its own, cruising somewhere between 60-70mph.
However, the second I get behind a big truck, and he's at least 4 car lengths infront of me, it goes up a good 1.5mpg easily.
If I get even closer, say two car lengths, (A bit closer than preferred for safety, but doable), The RX-8 sits at 24mpg indefinitely.
I've made long trips with the RX-8, with mostly drafting, and only using cruise control adjustments in 6th grear, and I've gotten 24mpg straight for the whole tank. "decent" fuel economy is possible, if not practical.
I've clocked 320mi on the odometer before having to fill up, and I think that is fantastic. There should be another gallon in the tank at that rate as well, but I'd rather play safe than sorry.
#2
Shakezula, the Mic Rula
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That's fine and all, but as soft as the 8s paint is.... I think i'll continue passing huge trucks and eat the gas.
Cool discovery though, makes sense.
Cool discovery though, makes sense.
#10
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I had my cruse set at 60mph for half a tank and did 206 miles at 7.5gals.....27.5mpg. 04/ AT....its boring in the slow lane....but fun to see what it could do.
#12
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Drafting increasing your gas mileage definitely makes sense and here is why. Why Mazda or any other car company tests fuel efficiency for a new car it is done in a very controlled environment. This means the car is tested at the absolute best conditions possible for driving which includes negating wind resistance in the factor. This is part of the reason when hybrids first came out they were not getting as good of gas mileage as everyone thought they would. No air resistance = better gas mileage. Putting a giant semi truck in front of you is drafting, which simulates zero air resistance if you are close enough. Truck drivers can be seen doing this with other truck drivers to allow them to driver further without filling up. It is no surprise that drafting increases your gas mileage, but like others have said trucks seem to throw a lot of rocks at my car, which I am not too fond of, but I will admit that I have drafted a truck on occasion on long road trips to help improve gas mileage somewhat.
#13
2005 Black RX-8 GT 6M
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Originally Posted by Old Rotor
I had my cruse set at 60mph for half a tank and did 206 miles at 7.5gals.....27.5mpg. 04/ AT....its boring in the slow lane....but fun to see what it could do.
#15
The Professor
I get 24mpg on long road trips. Just by setting the cruise control and keeping a steady pace without much passing.
I think most of the improvements in gas mileage that you are seeing are caused by you just staying at one speed and low throttle usage in the flow of traffic as opposed to passing people.
I think most of the improvements in gas mileage that you are seeing are caused by you just staying at one speed and low throttle usage in the flow of traffic as opposed to passing people.
#16
I had a conversion van pulling a large "shoebox" trailer when we went karting. 10 MPG. We teamed up with some freinds with a motor home & trailer often drafting them to other tracks. 15 MPG. Keep in mind a conversion van has the wind cD of about .8, and the trailer was a perfect 1.0.
The RX8 is pretty slippery in the wind already. I can see 3-4 MPG as possible but in my case that would come from driving 10 MPH slower....
The RX8 is pretty slippery in the wind already. I can see 3-4 MPG as possible but in my case that would come from driving 10 MPH slower....
#20
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I don't get the point of this thread... so you got an extra 1.5 MPG on a trip drafting behind some big truck.
Or an extra 15-20 miles per tank... ohh you almost saved $2.50 (if gas is $3/gal) on a tank of gas.
Wow you could buy a Big Mac or Whopper for hanging out behind a truck...
Or an extra 15-20 miles per tank... ohh you almost saved $2.50 (if gas is $3/gal) on a tank of gas.
Wow you could buy a Big Mac or Whopper for hanging out behind a truck...
#21
I'd rather let my 8 breathe in fresh cool air, as extended drafting like this on a hot day could be an overheating concern. Personally I stay as far away from large trucks as possible.
#22
Culpam Poena Premit Comes
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I dunno what it is with you american guys but just recently, i got 420km (262.5 miles) on half a tank! mostly freeway driving and some city driving?
#23
jersey fresh
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Originally Posted by DrewMan
I dunno what it is with you american guys but just recently, i got 420km (262.5 miles) on half a tank! mostly freeway driving and some city driving?
#24
Resu Deretsiger
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Originally Posted by DrewMan
I dunno what it is with you american guys but just recently, i got 420km (262.5 miles) on half a tank! mostly freeway driving and some city driving?