Nice it is removable.
Ian,
Petty bars are also used in NASA CCR if your rear stays are not to spec or you're missing them completely. You sometimes see some roadster race cars (and like 914's and Fiero's) with them that have little to no room behind the cage for the rear stays.
15.5.11.A Rear Braces - Exceptions
On cars where the rear window/bulkhead prohibits the installation of rear braces
(Porsche 914, Pontiac Fiero, etc.) the main hoop must be attached to the body by
plates welded to the cage and bolted to the stock shoulder harness mounting location.
There must also be a diagonal bar connecting the top of the main hoop to the lower
front passenger side mounting point (“Petty bar”). Some cars built for racing in other
recognized sanctioning bodies may be granted a waiver of this rule, however they must
show proof of compliance with the current published rules for their class.
Ian,
Petty bars are also used in NASA CCR if your rear stays are not to spec or you're missing them completely. You sometimes see some roadster race cars (and like 914's and Fiero's) with them that have little to no room behind the cage for the rear stays.
15.5.11.A Rear Braces - Exceptions
On cars where the rear window/bulkhead prohibits the installation of rear braces
(Porsche 914, Pontiac Fiero, etc.) the main hoop must be attached to the body by
plates welded to the cage and bolted to the stock shoulder harness mounting location.
There must also be a diagonal bar connecting the top of the main hoop to the lower
front passenger side mounting point (“Petty bar”). Some cars built for racing in other
recognized sanctioning bodies may be granted a waiver of this rule, however they must
show proof of compliance with the current published rules for their class.