Fitting Inertia Reel Seatbelts to a Rover P5 and P5B. Once I’d stripped the carpet, seats and console from the interior, the plan was to fit inertia seatbelts to make things more comfortable, and fit rear seatbelts as well so I can carry my 6 year old in some safety. You can buy Securon belts that are specced for the P5B, they come in beige which matches the interior colours pretty well, and Rover has seatbelt mounting points front and rear. So they were ordered.
On trying to fit them it became clear that there were two problems: the base of the B-post is angled at about 25 degrees, so the inertia reel wouldn’t work, and the seatbelt mountings on the rear shelf aren’t located to allow an inertia reel to be mounted – they hit the rear screen. Here’s the base of the B-pillar:
Obviously the mounting points weren’t made with inertia reels in mind. Much discussion with John at J R Wadhams revealed the fact that Rover changed the design of the B-pillar and rear shelf sometime around 1969 or 1970 to allow inertia reel belts to be fitted. Mine’s a 1968 model. Curse-word. Now what.
After a lot more head scratching and too many cups of tea I decided to make brackets for the front belts that have a 25 degree bend to mount the inertia reels upright. These were made in 5mm thick steel and sprayed so they didn’t look too terrible. Here’s the drawing I made after doing some CAD (Cardboard Aided Design):
Quite pleased with the results once things were sprayed. Here’s the front mounts:
These were made long so that the reel is effectively moved up the pillar so they don’t interfere with the front seats sliding back. The force in an accident is upwards to the top mount on the pillar, so they’ll be very strong.
The rear belts were a further complication – the rear parcel shelf is hollow, with wooden bracing and a hardboard covering, so it’s obviously not suitable to bolt seatbelts to or through – even if the bolts were long enough (they weren’t) the bending force on them in an accident would be significant. So I needed another solution, something to move the mounting points inwards whilst spacing the reels above the level of the parcel shelf. I came up with what I call ‘the beam’ – a hollow box section of steel, the bottom of which bolts to the original mounts on the rear parcel shelf, and allows the rear inertia reels to bolt to the top of it. I could also make it tall to raise the rear belts off the rear parcel shelf so they don’t loop-over the rear seats quite so much (that would wear the leather pretty quickly and fray the belts). This is what I came up with:
And here it is being sprayed:
Here it is mounted on the rear shelf, using standard seatbelt bolts:
It’s 4mm thick steel, and is heavy (quite in keeping with the Rover, really). In a major crash the very worst that could happen is that the top of the box section moves forward slightly and flattens the box section, moving the reels 1-2cm forwards. But the beam is the full width of the rear seat, so the force would be distributed right along the beam, so it’s unlikely to happen anyway in my view.
I then needed to cut-down the rear parcel shelf to fit behind the beam, so I did this. The cut-out in the middle is for the rear speaker, which I covered later with an MDF arc and beige speaker cloth:
Once that and the beam were covered in beige vinyl, as per the original rear shelf, it all looked quite good. The beam does cover part of the rear speaker opening, and I did consider cutting an arc out of the beam to allow for this, but decided that a) that was too much trouble and b) it was better to prioritise strength over sound quality. A central speaker isn’t exactly hifi anyway, and the period radio I’ll fit will add to that further, so I really don’t care. I also added a rear speaker cover behind the beam, made from MDF and beige speaker cloth, and bought a new speaker (the original one was somewhat the worse for 46 years exposure on the rear shelf). Here’s the end result:
As mentioned previously, I also got a pair of reel covers for the rear belts, after contacting Securon and asking why they didn’t supply them any more – apparently they decided a few years ago they weren’t necessary. But a very nice lady at Securon found a pair in the warehouse and sent them to me for free. Thank you.
In an ideal world they’d be beige, but I’m happy with the result.
After I managed to remove a stuck seatbelt bolt from the rear wheel arch (all the mountings are very solid, luckily) I finally managed to get the seatbelts fitted. What I thought would be an afternoons work eventually turned-out to be about 6 weeks of thinking, getting frustrated, technical drawing, metalwork, woodwork, spraying, upholstery and finally getting them fitted. All part of the classic experience I suppose.