New fairing for Gobi Roof rack

[Aznisegi]

Right now, my fairing feels like a wind sail. I expected it would be worse, but this is WAAAY different. Most have told me that the fairing is installed perfectly. I have no whistling or any other problems. However, my gas mileage took a royal dump. I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving.

I'm thinking about designing and making a new fairing for the gobi rack. I had an aerospace buddy here at Lockheed recommend changing the angle and wrap of the fairing. he said it could improve the gas mileage substantially at higher speed if the fairing was redesigned. We were also looking at making a cover the 40" bar for aerodynamics too.

Should I say screw it? lol

 

[Sound_SS]

Right now, my fairing feels like a wind sail. I expected it would be worse, but this is WAAAY different. Most have told me that the fairing is installed perfectly. I have no whistling or any other problems. However, my gas mileage took a royal dump. I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving.

I'm thinking about designing and making a new fairing for the gobi rack. I had an aerospace buddy here at Lockheed recommend changing the angle and wrap of the fairing. he said it could improve the gas mileage substantially at higher speed if the fairing was redesigned. We were also looking at making a cover the 40" bar for aerodynamics too.

Should I say screw it? lol

i think a cover for the light bar could be interesting.
but i wouldn't call a mileage drop of .3 mpg "a royal dump".............

 

[TfourR]

Right now, my fairing feels like a wind sail. I expected it would be worse, but this is WAAAY different. Most have told me that the fairing is installed perfectly. I have no whistling or any other problems. However, my gas mileage took a royal dump. I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving.

I'm thinking about designing and making a new fairing for the gobi rack. I had an aerospace buddy here at Lockheed recommend changing the angle and wrap of the fairing. he said it could improve the gas mileage substantially at higher speed if the fairing was redesigned. We were also looking at making a cover the 40" bar for aerodynamics too.

Should I say screw it? lol

Not only did the aerodynamics change, but you added more weight too. Pretty normal to suffer MPG decline.

 

[speedoman]

user [MENTION=128995]TK-422[/MENTION] put one on his Prinsu rack over his lightbar. Could ask him.

 

[Aznisegi]

Not only did the aerodynamics change, but you added more weight too. Pretty normal to suffer MPG decline.

The MPG decline isn't from the weight. There isn't enough weight to see that significant of a change. I had 16.0 MPG averaged over SEVEN THOUSAND miles. To see a .3 MPG decline in just 200 miles of driving after install is insane. The weight of that rack isn't significant enough to shift MPG that much. Therefore, the aerodynamics is the likely culprit.

 

[TfourR]

The MPG decline isn't from the weight. There isn't enough weight to see that significant of a change. I had 16.0 MPG averaged over SEVEN THOUSAND miles. To see a .3 MPG decline in just 200 miles of driving after install is insane. The weight of that rack isn't significant enough to shift MPG that much. Therefore, the aerodynamics is the likely culprit.

Yes you absolutely can see that amount of MPG change with the combination of the two. Any time you add more weight you run the risk of MPG loss. 0.3 really isn't that much of a loss though.

 

[T4 Leaf]

Yes you absolutely can see that amount of MPG change with the combination of the two. Any time you add more weight you run the risk of MPG loss. 0.3 really isn't that much of a loss though.

I'm only a potential-future Gobi owner, but I'm thinking the massive cost and wait time for one outweighs the pain/cost of the mpg drop...but both are dwarfed by how damn cool and capable they are.

 

[Brandonium]

I consider such a small MPG change for what you added to be insignificant. If MPG is a big concern for you then you should not be performing any modifications to the vehicle as it is.

Right now, my fairing feels like a wind sail. I expected it would be worse, but this is WAAAY different. Most have told me that the fairing is installed perfectly. I have no whistling or any other problems. However, my gas mileage took a royal dump. I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving.

I'm thinking about designing and making a new fairing for the gobi rack. I had an aerospace buddy here at Lockheed recommend changing the angle and wrap of the fairing. he said it could improve the gas mileage substantially at higher speed if the fairing was redesigned. We were also looking at making a cover the 40" bar for aerodynamics too.

Should I say screw it? lol

 

[TfourR]

I'm only a potential-future Gobi owner, but I'm thinking the massive cost and wait time for one outweighs the pain/cost of the mpg drop...but both are dwarfed by how damn cool and capable they are.

I completely agree. I definitely wouldn't complain about a 0.3 MPG loss after a roof rack install. Well worth it in my eyes.

 

[Sound_SS]

The MPG decline isn't from the weight. There isn't enough weight to see that significant of a change. I had 16.0 MPG averaged over SEVEN THOUSAND miles. To see a .3 MPG decline in just 200 miles of driving after install is insane. The weight of that rack isn't significant enough to shift MPG that much. Therefore, the aerodynamics is the likely culprit.

come back in 6,800 miles and report your average. you could have had a tank of gas that wasn't quite right. or 200 miles into a strong headwind lol.
are you really that worried about this? and how are you calculating this? you're hand calculating this i hope, which would mean filling up at 200 miles after rack install?

 

[5280 TRail-Runner]

MPGs? LOL.. Get a Prius if you are worried about miles... But on a serious note, .3 is nothing, even over 200 miles of driving. You probably got heavy footed and got excited after you got the rack installed. I know I did... lol I have a rack, bigger tires, lift and I still get on average about 17-17.5mpg. Its all about how you drive. Getting a scangauge definitely helps with learning how to drive for better mpg. It also helps that we have so many hills here in CO so I coast downhill every chance I get which makes up for the loss of mpg going up them... haha Enjoy the ride man, I would worry so much about such a small loss. :cheers:

 

[4Roamer]

I think you and your aerospace buddy have a business idea. Not that ANYONE (cough cough) around here spends money on such frivolous products.:flame:

 

[cmilviper]

Right now, my fairing feels like a wind sail. I expected it would be worse, but this is WAAAY different. Most have told me that the fairing is installed perfectly. I have no whistling or any other problems. However, my gas mileage took a royal dump. I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving.

I'm thinking about designing and making a new fairing for the gobi rack. I had an aerospace buddy here at Lockheed recommend changing the angle and wrap of the fairing. he said it could improve the gas mileage substantially at higher speed if the fairing was redesigned. We were also looking at making a cover the 40" bar for aerodynamics too.

Should I say screw it? lol

You call a drop in gas mileage of .2-.3 as taking a "royal dump"? Hahaha

(With the potential newly designed fairing) I'm sure when you say it "will improve gas mileage substantially", you consider .05-.1 substantial? Hahaha. Good luck.

 

[CoolMax]

after sliders, skids, & tires, it was the Gobi that knocked off at least 1.5mpg for me.

 

[Aznisegi]

"I was at 15.9 averaged across the full mileage with ~7000 miles on my truck. After installation, I dropped to 15.7 and soon to be 15.6 within 200 miles of driving."

If I wasn't clear, that'd be 15.9-16 MPG through the entire 7K miles... meaning I never reset my MPG counter. Even then, after install, in a mere 200 miles I've seen a .5 MPG (now) decrease without ever resetting my MPG counter. We're making a new fairing, which should be a fun project. It's also to reduce a good amount of the wind noise as well at 65-70 mph when the wind pattern changes over the vehicle.

I usually don't settle for "deal with it" as an answer. Just seeing if anyone else has tried it or experimented with a different fairing.

 

[kevinmai712]

curious... is your name An?

 

[Aznisegi]

That's me! Who's asking?!??!

 

[boyguan]

I would make a new fairingif I could if it could gain me back a bit of mpg why not? Now to weigh it. If you spend 200 on the fairing. How long will it take to recoup the cost of gas backto break even or even reduce it

 

[Aznisegi]

If I was doing it myself, it wouldnt cost nearly that much. Access to materials and tools!