Trunk Prop Rod Replacement

This is  a perfect plan for doing the modification in addition to including the source for the
cylinders as well as the cylinder part numbers.
This modification  will appeal to many as this deals directly with something we do frequently on
our cars and makes it a lot easier.
Courtesy of Alan Bromfield,
“I installed a gas strut to the boot lid of the BN4 to eliminate the need to use two hands when
propping or closing the boot. Since this is usually done to put something in or take something
out, then one hand is inevitably holding the item which has to be placed on the floor. The
secondary issue I had was that on a couple of occasions I managed to bash my head on the boot
latch hook since access to the boot is by ducking under the inclined lid.
I felt that a gas strut solution could be introduced that would allow the lid to be opened and
closed with a single hand and would hold the lid vertically (out of the way) whilst also
eliminating the steel wire secondary protection.
I fabricated a simple bracket that bolts on the boot lid hinge studs for the upper end.
For the lower end I replaced the bracket that the prop rod normally hooks into with a plate and
brace for the bottom of the strut to mount to. This picks up the original holes of the prop rod
bracket so if a future owner wants to revert to standard it is simple to do so. The shroud lip
isn't really strong enough to withstand the spring pressure from the strut so the back of the
bracket is braced back to the inner wheel arch where it connects to a shroud/wing bolt.
I assessed the fully open length of the strut I would need and sourced it online from
An SD01-200 with a fully open length of 440mm was used. With the addition of the ball-ends
required the overall length resulted in the boot lid being almost vertical when open whilst also
providing enough stroke length to allow the lid to close.
When delivered the strut is pressurised to a spring tension that is almost solid. The pressure
can be bled off a little at a time (there is no going back if you overdo it) until the lid is
actively pushed open from about 30% open. The angles involved cause the strut to gain mechanical
advantage as the lid opens. The pressure of the spring is a matter of personal preference; too
much will stress the shroud and too little won't lift the lid. E.xperiment
Trunk Prop Rod Replacement
A simple bracket for the upper end that picks up on the boot hinge studs.
Behind the lower mounting a brace bolts back to the inner wing.
Gas Cylinder in Action
Cylinder Upper Mount to Hinge Bolts
Cylinder Lower Mount
Fabricated Strengthening Brace
The Gas Strut Used