Planning is all
How I made my own roll bar between rulebook and saving the SS.
First get to know your Impala SS inside out. Figure out where the roll bar has to go. I made a choice to
anchor the rear bars by bolting them into 2 layers of strong formed body sheets with hundreds of welding,
press and folding points - rather than into the frame which would've been more of a narrow layout
closer to the centerline of the car. The two layers are the "hat-rack" where the audio speakers are
mounted and the wheel inner fenders. I believe that this could be as strong as the rear subframe itself.
Not only because of the collected mass of metal material that is engaged but also the amount of
wide spread fastening points.
Locate. Measure.
The idea is also to split the rear bar at the "hat-rack" to spread the strength via the bolted steel plates
and not just let the bar go through this layer unattached. And before I even started to work with it I got
this layout scrutinized and approved by the Dragracing Tech Department at the Svenska Bilsportförbundet,
the body of all Swedish motorsports. Our dragracing rules are based on the NHRA's rules in the USA.
I carefully drew a pair of explaining illustrations and applied for an exemption from the rules and got it.
So I didn't take a chance on this.
Of course I intended to keep the comfortable SS interior - chairs, steering wheel and control panel. But
that makes it too tight if adding a 1 3/4" forward bar from the main hoop to the floor. I would have big
problems to exit the car through the doors - even without a crash! So I applied for an exemption from the
rules to not to have that forward bar - and it was accepted. When I'll someday build a roll cage, these
forward bars will be the biggest challenges. Because I want to keep the interior!
More NHRA rules: http://www.nhra.com/contacts/tech_faq.html
Now get big cardboard. Behind a TV-shop.
Then have a cardboard cutting orgy. Visualize it being 1 3/4" and be careful. Think it over and over again.
"Can it really be bent and done this way?" "What am I doing here in the middle of the night? Again!"
"Maybe I should just buy one finished?"
