4 point harnesses vs inertia reel

[lowlander]

My 1994 car has 3 point inertia reel sealbelts and I'm thinking about getting a pair of 4 point harnesses.

 

I'm assuming that the mounting points are already there but how much of a fiddle is it to install the harnesses?

 

The car is only used on the road.

 

Cheers.

 

Martin.

 

 

Lowlander

1994 1400SS, 6 speed, clams

[Normans_Ghost]

If you have the mounting points it's very easy.

 

remove seats

 

Screw the ends into the threads welded to the chassis. two behind seat on the top rail and one each side of the seat just in front of the cockpit back panel.

 

refit seats.

 

I cannot remember if the seat belt bolts are 11/16" or 3/4" AF but can check if you want. I'm not sure what seats you have or how easy thay are to remove/refit.

 

 

sorry ed to answer. I don't think anyone would disagree (want a bet?) that 4 point are safer than 3 point. If the car was upside down the 4 point would hold you tight in the seat (assuming they are adjusted correctly). I can imagine a 3 point wouldn't keep you tight in the seat if you were rolling over.

 

^{Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here}

You and your seven toThe French Blatting Company Limited

 

Edited by - nverona on 30 May 2009 11:08:28

[abbot]

Norman

You are right, a properly adjusted 4 point harness will hold you in place more securely than a three point inertia reel system. One of the down sides of the comfort of Inertia Reel systems is that they are not usually as tight at the start of the impact. This can be due to position and movement of the occupant or loose clothing, thick jumpers, coats etc. This is why a lot of modern high scoring Euro NCAP cars are fitted with retractor, buckle or 3rd point pretensioner systems. These are designed to pull in the slack and tighten the belt before the occupant start to move forward in the impact.

The reason that more road cars are not fitted with 4 point belts as standard is comfort and I believe the regulation requires that the belt must be able to be buckled up using only one hand.

 

Chris

 

1700ss BRG/Yellow Stripe the only way to cruise

 

Edited by - Abbot on 30 May 2009 13:26:48

[Stationary M25 Traveller]

You won't regret it. Easy to fit, but you will probably leave the inertia reel unit hidden inside the bodywork, and leave the free buckle taped up and cable-tied to the back of the seat frame. The inertia reel is well hidden and an impossible pain to get at ... behind riveted panels, so I left mine where it is !

 

 

[MADMALC]

Go for the crotch strap as well. This stops the buckle from riding up into a dangerous position.

I personally would not be without the extra strap. I would suggest that the 3 point is more likely to maintain the correct position on the torso than a 4 point without the crotch strap.

 

S7MAD

[shn7]

Agree with MADMALC. For little extra cost the greater security in the seat is a must. I always found that without the crotch strap the lap belt rides up your stomach which in the event of a big impact would probably do you considerable harm.

 

Steve.

Sussex (West) AR

Not forgetting Percy the Polar Bear who recommends

Puddle Pet Care

[abbot]

When the occupant goes down under the lap portion of the belt it is called submarining. Again on normal inertia reel belts this risk can be reduced with lap portion of the belt being tightened with buckle or third point pretensioners. There are certain models of car that are fitted with a inflatable cushions that deploy under the thighs to stop submarining.

 

Crotch straps on harnesses also need to be adjusted carefully. If you are not squemish you can search on pistonheads to see what happens if they are not.

Chris

 

1700ss BRG/Yellow Stripe the only way to cruise

[Lotus Boy]

Totally agree with all the comments about not feeling safe with just inertia belts so the first thing I did to my car was fit a set of Willans 4 point harnesses. I did the same as SM25T. Left the inertia reel belts in place as there was enough thread on the bolts to have both fixings so not a problem.

 

I've never used my inertias but have used the passenger side one a few times to either hold things in place like a rucksack or when I have given rides to friend's children. I put both belts on them for good measure.

 

Cheers

Dave

 

Edited by - Lotus Boy on 31 May 2009 11:19:45

[john milner]

I thought about a 4 point harness but after considering the downsides of what could happen if it rode up I stayed with the inertia reel and a bought a CG-Lock to get most of the handling benefits. I've seen the Pistonhead pics and that put me off 4 + crotch strap. Probably the best is a very tight harness but for me that would be too inconvenient so I would probably get lazy and not tighten it every time I put it on.

[7 wonders of the world]

Willans 6 point belts , I think the ones from the bulk buy on here were the Silverstone model which come with the adjusters the correct way for a 7 and the belts are handed unlike the CC versions so the buckle is inboard on both belts - helps prevent the passenger belt being thown into the outside of the car 'anchor style' and denting the bodywork ☹️

 

I too find that you slide under a 4 point leaving the belt accros your stomach when it should be over your hips

 

Do a search in the Archives for around 3 1/2 years back

 

Too young to be old !

[Stationary M25 Traveller]

You can easily move the buckle on CC harnesses, so it is on the inside for both seats.

 

 

[woodfell]

When I moved from inertia reel to 4 point harness I initially cut off the buckle of the inertia reel belt and let it retract all the way back into the reel as I did not want it banging around in the car. Later, when I fitted new rear shocks I then undrilled the side panels in the wheel arches and removed the reel altogether.

[r300csl]

Even with the crotch strap you need to make sure you have them correctly adjusted: see link (not for the squeamish)

 

Edited by - r300csl on 1 Jun 2009 13:10:15

 

Edited by - r300csl on 1 Jun 2009 13:14:10