installing five point harness

[RA64]

does anyone know where I can find some sort of instructions on the mounting points for a five-point simpson camel-lock style harness?

I'm installing the seatbelts in a custom built (solar powered) car. it is kinda complicated to describe the situation but I'm wondering of we can mount the shoulder belts to the roll cage at floor level a few inches behind the back of the drivers head/upper back. The belts could go through the seat back and through or over a part of the carbon fiber chassis at shoulder level or slightly below, then almost vertically down to the floor. Does anyone know if this is okay? The other option would be mount them on a bar about an inch above the drivers shoulders, and slightly above the shoulders.

If anyone has any experience with this please respond, I can try to describe the situation in more detail if necessary.

[TheSilentChamber]

It sounds almost like your driving is going to be laying on his back?

[2.2 Straight six]

Originally Posted by RA64

does anyone know where I can find some sort of instructions on the mounting points for a five-point simpson camel-lock style harness?

I'm installing the seatbelts in a custom built (solar powered) car. it is kinda complicated to describe the situation but I'm wondering of we can mount the shoulder belts to the roll cage at floor level a few inches behind the back of the drivers head/upper back. The belts could go through the seat back and through or over a part of the carbon fiber chassis at shoulder level or slightly below, then almost vertically down to the floor. Does anyone know if this is okay? The other option would be mount them on a bar about an inch above the drivers shoulders, and slightly above the shoulders.

If anyone has any experience with this please respond, I can try to describe the situation in more detail if necessary.

are you saying there's a solar-powered car fast enough to cause substanial damage, requiring 5-point harnesses? whoa...

it shouldn't matter whether the harnesses bolt to the floor behind the seat or onto a bar on the roll-cage behind the seats, usually when the harness' top straps are bolted to the floor they're anout two feet behind the seat and not directly behind.

[Moppie]

ITS IF VERY IMPORTANT YOU MOUNT THEM CORRECTLY.

How they are mounted is determined by the manufactors recomendations, and the legal requirments of any motorsport bodies in your country.

All the Harness's I have install have come with instructions on mounting angles relative to the person in the seat, and I know the MANZ hand book (motorsport association of NZ) also has very strict guidlines on the angles the belts are allowed to take in relation to the person in the seat, and what they can be attached to.

If the angle of the shoulder harness is to wrong the person in the seat can either submarine out the bottom of the harness (painful if a crotch stap is used) or the harness can compress their shoulders causing spinal damage among other injuries during an accident.

If you can find nothing, and trust my memory, then the shoulder harness should be at an angle of between 5-15 degs down from the horizontal back to where it is mounted in the car. This will hold the person in the seat from going forward, and provide a small amount fo downward pressure to stop them going up, but not so much as it will crush them down.
The lap belts should come from behind the persons hip and go accross the lap.
The crotch stap should come over the front of the seat, so it is mounted slightly under the seat. This stops the person in the seat slipping between the belt and seat in a crash.

[RA64]

the driver is laying in a very reclined position. this is also a challenge for the lap and crotch belt, as the seat is basically the floor, and it seems difficult to prevent submarining.

I read somewhere else the shoulder belts should be mounted 0-10 degrees down from horizontal, thats all i could find. is there anywhere i can find manufacterers specs online?

If the shoulder belt wraps around part of the chassis that is a few inches behind the seat back at about a 5 degree angle, and then goes almost strieght to the floor, would this be okay?

[TheSilentChamber]

In that reclined of a position if you hit something fron the front at substantial speed your going to be dealing with things such as dislocated hips, groin damage, and high pitched voices for the rest of your life.

[RA64]

well, i don't think its any more reclined then a F1 or champcar/indycar.

[Moppie]

You might be able to position the lap belt such that is well accross his hip so that he can not slip under it, then use the crotch belt to hold the lap belt down to stop it sliding up in a crash.

You might want to try and get hold of a motorsport association in your area, or a local car club with an active motorsport based membership, and Im sure you will find someone who can give you soem advice.
Its not the sort of thing you want to get wrong.