Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

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twr7cx
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Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby twr7cx » Sat Sep 21, 2019 11:04 pm

Surprisingly I couldn’t find a thread about this already. I’m seeking experiences on Brown Davis Roll bars to suit the NA/NB. I was set to go the Automotive Plus Torque Box (Standard not Tall Boy) route but some Brown Davis units have been popping up on the used market which is tempting.

It’s not for a track car so neither CAMS nor mod plate is of concern.
I believe that the Brown Davis is the taller of the two.

Standard seat belts and NB Surfboard seats will be used. I’m particularly interested to know if the Brown Davis roll bar effects the seat recline or for/aft adjustment, and if it effects the operation of the standard seat belt, particularly its ability to retract?

It seems that they offer two version - one for glass and one for plastic rear window. Is either compatible with box?

Any other thoughts or comments?


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Last edited by twr7cx on Sat Sep 21, 2019 11:04 pm, edited 2 times in total.

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KevGoat
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby KevGoat » Sat Sep 21, 2019 11:27 pm

My BD bar use to affect the seat belt retract in my NA, it also affected some if the aft seat movement and/or recline, but not so majorly I ever really thought about it. By comparison the Automotive Plus twin hoop in my NB SE sits back further and affects neither. The BD bar gave an improved feel to the structural integrity of the car but the "torque box" of the Auto+ bar gives a noticeable improvement.

Oh btw I had the NB surf board seats in my NA as well.

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twr7cx
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby twr7cx » Sun Sep 22, 2019 7:29 am

Perfect, just the kind of details I was after. Thanks KevGoat.


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Danny
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby Danny » Sun Sep 22, 2019 9:11 am

I've recently fitted the BD bar. No problems with either the seat travel or belts.

The difference between the glass and plastic window bars relates to the locations of the diagonal brace. It can go at an angle from the rear bolt mount to the hoop or vertically from the lower corner of the hoop to the opposite high corner of the hoop.

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KevGoat
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby KevGoat » Sun Sep 22, 2019 12:08 pm

Found a couple of old photos that might sort of show how each bar sits if that's any help. The Automotive Plus single bar sits the same as the twin hoop (from memory) but their Tall Boy bar sits a lot further forward than any of these.

BD in my NA6
Image

Twin hoop in my SE
Image

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Mr Morlock
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby Mr Morlock » Fri Oct 11, 2019 7:49 pm

I never understood the fitting a roll bar for a non race track car. A roll bar close to the head is not a good idea considering getting rear ended is not uncommon. The question is what is the safe distance between head and roll bar when seated.

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KevGoat
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Re: Brown Davis NA/NB Roll Bar - does it effect seat belt retract or seat position?

Postby KevGoat » Fri Oct 11, 2019 8:54 pm

In SA the requirement is 100mm when the seat it is in the most rearward position...

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