Fitting harnesses

[Liams dad]

I

I've always had inertia reels on my SR, wouldn't bother with harnesses due to the restrictivness .
Have got a set of Willans harnesses sitting in my garage just in case I feel the urge for a track day !
Had them for over twenty years now .
Chris.

I am now convinced 

[Chris]

I've always had inertia reels on my SR, wouldn't bother with harnesses due to the restrictivness .
Have got a set of Willans harnesses sitting in my garage just in case I feel the urge for a track day !
Had them for over twenty years now .
Chris.

[Liams dad]

Harnesses look good, but it all depends on your attitude to risk. I have seen upper harness belts bolted to floor pans in the boot, or worse still in the cockpit. In the event of a sudden impact these will attempt to compress the occupant's spine. They should ideally be mounted at a secure location within a few degrees of a horizontal line with your shoulders. There are some diagrams on the web you can look at.   
e.g. here... https://forum.mx5oc.co.uk/t/harness/76560

On the Sumo, I would suggest a triangualed frame around the petrol tank would do the trick. In my opinion, others may disagree, the worst thing you could do is drill a hole in the grp behind the seats and slap a spreader plate on the back.
 
I was going to fit harnesses, particularly as my IVA inspector made me add triangulation to the Crendon seat belt turret (the only such Crendon ever to have this fitted ), but have decided against it. Inertia reels are so much less faff and more convenient for every day driving rather than racing in a fxed driving position. Maybe I am just getting old.

Just to be clear: I am not a structural engineer, so my views are worth exactly what you paid for them! - to quote an ex-forum member.

Thanks for the link and the above... I'm now staying with inertia belt. I didn't consider the the lack of movement and I'm not going on the track.

Regards A

[KevinW]

Harnesses look good, but it all depends on your attitude to risk. I have seen upper harness belts bolted to floor pans in the boot, or worse still in the cockpit. In the event of a sudden impact these will attempt to compress the occupant's spine. They should ideally be mounted at a secure location within a few degrees of a horizontal line with your shoulders. There are some diagrams on the web you can look at.   
e.g. here... https://forum.mx5oc.co.uk/t/harness/76560

On the Sumo, I would suggest a triangualed frame around the petrol tank would do the trick. In my opinion, others may disagree, the worst thing you could do is drill a hole in the grp behind the seats and slap a spreader plate on the back.
 
I was going to fit harnesses, particularly as my IVA inspector made me add triangulation to the Crendon seat belt turret (the only such Crendon ever to have this fitted ), but have decided against it. Inertia reels are so much less faff and more convenient for every day driving rather than racing in a fxed driving position. Maybe I am just getting old.

Just to be clear: I am not a structural engineer, so my views are worth exactly what you paid for them! - to quote an ex-forum member.

[Liams dad]

I don't know of any official instructions, but my suggestion, for what its worth.....

1. Unbolt the inertia seat belts
2. Use spreader plates to attach harness lower straps.
3. Install triangulated frame for installation of upper mounting point as high as possible to avoid spinal compression in the event of an accident.
4. Install crotch strap to avoid submarining in the event of an accident.

Many thanks for your reply,
What do you mean by triangulated frame is that something I have to make to fit behind the rear bulkhead

Alistair

[KevinW]

I don't know of any official instructions, but my suggestion, for what its worth.....

1. Unbolt the inertia seat belts
2. Use spreader plates to attach harness lower straps.
3. Install triangulated frame for installation of upper mounting point as high as possible to avoid spinal compression in the event of an accident.
4. Install crotch strap to avoid submarining in the event of an accident.

[Tony]

What car do you have Alistair?

It's in the Pilgrim section.........   

[Ldw]

Hi,

Does anyone have any details for fitting  harnesses and removing the inertia seat belt

Regards Alistair

What car do you have Alistair?

[Liams dad]

Hi,

Does anyone have any details for fitting  harnesses and removing the inertia seat belt

Regards Alistair