Light Bar.

[Tonks]

Do you think if i mount a Light Bar on the top of the Bullbar it will affect the flow of air into the scoop on top of the bonnet, do i need to be concerned about it,
Cheers
Tonks.

[MudRunnerTD]

Every time I see one mounted above the bar this is my first thought!! It Must get in the way of air flow! Must.

[Rock Trol]

I saw a video on You Tube where a guy had taped pieces of cotton yarn to his Patrol bonnet to see if he was getting air flow into the intercooler with a bull bar on. There had been speculation that no air gets forced in the factory scoop because its low and the bull bar changes the air flow. The video shows that the air flow was not disturbed and cotton pulled backwards when driving so there was air flow over the surface of the bonnet.

A similar test from someone with the light bar on top of the bull bar would be a good step to see what the affect is. I will try and find the video.

EDIT - here are a couple of videos off you tube, there are more.

https://www.youtube.com/watch?v=s7GjbZWWLjU

https://www.youtube.com/watch?v=v_rfgBJPnOw

[threedogs]

II think even a bull bar disturbs the air going to the scoop. I've filled in the gap between the bullbar and bonnet.
Can you mount a 600mm bar in between the uprights?

[mudski]

You might want to check the legalities of mounting on top of the bull bar too....

[Tonks]

I saw a video on You Tube where a guy had taped pieces of cotton yarn to his Patrol bonnet to see if he was getting air flow into the intercooler with a bull bar on. There had been speculation that no air gets forced in the factory scoop because its low and the bull bar changes the air flow. The video shows that the air flow was not disturbed and cotton pulled backwards when driving so there was air flow over the surface of the bonnet.

A similar test from someone with the light bar on top of the bull bar would be a good step to see what the affect is. I will try and find the video.

EDIT - here are a couple of videos off you tube, there are more.

https://www.youtube.com/watch?v=s7GjbZWWLjU

https://www.youtube.com/watch?v=v_rfgBJPnOw

Plenty of air flow over that bonnet.

[threedogs]

does that gu one have a bullbar, From what I know its illegal to mount a light bar on top of a bullbar.
Also a GU scoop will work best at speeds of 85kph and up, if you're lucky enough to have an ARE scoop
it will work at around 65kph

[Rock Trol]

does that gu one have a bullbar, From what I know its illegal to mount a light bar on top of a bullbar.
Also a GU scoop will work best at speeds of 85kph and up, if you're lucky enough to have an ARE scoop
it will work at around 65kph

The white one does. Looks like standard Nissan steel bar. You can just make it out on another of his videos where the camera is inside the car. No light bars on top though.

[Patrol'n]

My understanding of the legalities is that lights must be in pairs and never mounted higher than the original headlights, but that's just what I've been told and from what I could find in documentation, so just my opinion! I would guess this would also alter pedestrian safety ratings if they apply to the vehicle. Seen a lot of trucks with what must be illegal lightbars running around...

As for air flow, this would certainly create disturbance in the air flow, but whether or not it would decrease the amount of airflow to the scoop would be subject to many factors, such as whether it directly blocked the airflow, speed of travel, shape and position of the lightbar etc, if you've ever seen some of the testing of convertibles and cars produced with rear wings, there are pockets of swirling air, pressure areas etc, behind rear windows, cabin areas etc. Manufacturers spend a bunch testing this, I think it would be a difficult thing to verify without testing.

I would think it was safer not to put anything in the way of the scoop as reducing airflow where the factory engineers designed it to have airflow could be bad, particularly if it reduces cooling air to an intercooler...

Test or check with someone who installs them for a living perhaps. Maybe someone on the forum can help further? Better to be safe than sorry me thinks.

[threedogs]

@ Patrol'n they have changed the law on light bars there is a link somewhere.
You no longer need to mount them in pairs, but on top of the bullbar is a no no.
in Vic anything wider than 30mm I think ,limiting you just an antenna