MPG loss with Vector/Vision?

[SBFD-E-9]

I hope this is the correct spot for this. Has anyone figured up MPG loss while running a full size Vector/Vision bar? I know with most other lightbars it seems to be a loss of 1-2 mpg if any, just not sure on a Vector/Vision.


Thanks!


Dan

 

[EL1998P71]

Depends on the vehicle.


I have had a Vision on my Crown Vic and normally get around 14.38 MPG City without it,


I think it was something around 11-12 MPG with it.


Since the shape is a bit more forgiving than most bars, Like XL, LP, Edge, MX.

 

[HILO]

Actually, the LP was very good about air flow, hence the Low Profile tag (LP). The Jet Sonic and Force 4 LP could maintain and sometimes boost fuel economy. The V bars are heavy, and catch a lot of air flow underneath, as well as pushing from the top. Not really an economic bar. The MX and Edge are better for air flow. Keep in mind, all of the mentioned bars were designed in the 80's, for vehicles of the time.

 

[jdh]

Actually, the LP was very good about air flow, hence the Low Profile tag (LP). The Jet Sonic and Force 4 LP could maintain and sometimes boost fuel economy. The V bars are heavy, and catch a lot of air flow underneath, as well as pushing from the top. Not really an economic bar. The MX and Edge are better for air flow. Keep in mind, all of the mentioned bars were designed in the 80's, for vehicles of the time.

I think the key thing is they were not only lo profile.....but very light. Federal Signal always had heavy bars.

 

[nerdly_dood]

It always depends on the type of vehicle. Consumer Reports did a test where they put a rooftop carrier on a Toyota Camry and they lost about 5-6mpg highway, but then they put the same one on a Mercury Mountaineer and lost only 1. They put a ton of effort into the aerodynamic design of the Prius so if they'd put it on one of those it'd be more like 8. A lightbar is no different - on a vehicle with worse aerodynamics to begin with, you'll see a smaller drop in fuel economy, but on an aerodynamic car, it's a big parachute on top.