David Jenkins
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| posted on 8/4/05 at 12:11 PM |
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4-point harness problem
I have a problem with my 4-point harness lap belt riding up when I tighten the shoulder straps - sometimes it rides up on its own, while I'm
driving.
I believe that the first problem area is the position of the lower mounts - they're in the conventional place for lap-and-diagonals, but maybe
4-pointers should have them further forward (so they pull down instead of back).
One solution is to fit a 5-point harness, but I haven't a clue where the 5th one should be mounted (apart from somewhere around my crutch!).
I don't want to take my car to bits to fix this problem as I've only recently got it on the road... but I would prefer that the lap belt
wasn't sitting on my abdomen as I pelt down twisty Suffolk roads... 
Any practical suggestions? or Links to informative websites?
David
USEFUL LINKS (adding as I find them)
Willans
G-Force
[Edited on 8/4/05 by David Jenkins]
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alister667
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| posted on 8/4/05 at 12:28 PM |
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Our SVA tester took exception to this as well. IN the end I had to fit a full 5-point harness as the only way round it.
I secured a steel bracket to the floor crossmember with 2 bolts, and bolted the eye piece into that. The harness itself had to be a 5-piece racing
(twist release) type.
Hope this is of help
Ali
http://members.lycos.co.uk/alister667/
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locoboy
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| posted on 8/4/05 at 12:31 PM |
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mine used to do that too,
i used to tighten the lap strap first then the shoulder straps (not too tight)
other option is to develop an over lapstrap gut
ATB
Locoboy
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David Jenkins
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| posted on 8/4/05 at 12:50 PM |
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Ali,
Your 5th belt looks a long way in front of the seat - does it keep the lap belt in place?
Col - I already have a well-developed retaining gut - but I'd rather not rely on it!
David
[Edited on 8/4/05 by David Jenkins]
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timf
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| posted on 8/4/05 at 12:57 PM |
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david
iirc you can get additional add on crutch straps for normal harnesses the use hoops that fit near the buckle
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David Jenkins
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| posted on 8/4/05 at 01:12 PM |
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Tim,
I've heard of them, but can't find a link.
Anyone know of a link, or a name for a Google search?
David
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locoboy
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| posted on 8/4/05 at 01:17 PM |
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if you dont want it to be a structural part of the belt assembly then try this company for bits of webbing and
suitable adjusters etc.
ATB
Locoboy
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alister667
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| posted on 8/4/05 at 02:49 PM |
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David,
Yes it does it's job pretty well, the lap belts keep the buckle close to you, the crotch strap pulls it down and slightly away (doesn't
matter if your lap belts are anywhere near right) and the chest straps tend to pull up a bit.
Perhaps the photo is from a misleading angle - if the securing point was much nearer the front of the seat the belt mightn't clear over the
seat.
I do favour the overstrap gut idea though and have been working hard on this solution over the winter months!
quote:
Originally posted by David Jenkins
Ali,
Your 5th belt looks a long way in front of the seat - does it keep the lap belt in place?
Col - I already have a well-developed retaining gut - but I'd rather not rely on it!
David
[Edited on 8/4/05 by David Jenkins]
http://members.lycos.co.uk/alister667/
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givemethebighammer
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| posted on 8/4/05 at 03:41 PM |
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really the 5th (and 6th) straps should come up through the seat. Too far forward and the strap won't be effective in stopping you submarine or
will partially work and will cause you a injury in the process
I have cut a hole in my MK seats like the photo. The six points attach to the chassis under the seats. The belts all attach very snuggly (is that a
word ?). Hence the belts are all taking the strain at the time of the impact (my body moves very little before the belts restrain me).
just my 10p's worth.
 
Rescued attachment hole for six pts.jpg
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givemethebighammer
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| posted on 8/4/05 at 03:44 PM |
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my six pints came with these instructions and warning as follows:
Never run the anti-sub strap over the front line of the seat. Such an installation would eliminate ant-sub straps intended function. Submarining and
severe injuries may occur during a frontal crash.
(I have SCHROTH / safety devices harnesses)
[Edited on 8/4/05 by givemethebighammer]
 
Rescued attachment belts1.jpg
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alister667
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| posted on 8/4/05 at 04:24 PM |
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The SVA testers problem was that the buckle was too high and would allow submarining and also cause injury on impact being so high - if you tightened
the should straps up the buckle could go up towards the solar plexus.
I was under the impression it was the position of the buckle / cross straps that caused submarining, ie if they're too high. I reckoned that
the (single) lower strap's job was to pull the buckle/side straps into a safer position - NOT to take bodyweight in the event of a
crash/submarining. If you want it to do that job then you need a 6 point harness - a 5 point will have you singing falsetto surely?
Having it forward means my plums aren't in serious danger. Well, no more than normal.
I don't think I could get the 5th point much closer without cutting a lump out of my Cobra 7's anyhow!
http://members.lycos.co.uk/alister667/
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givemethebighammer
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| posted on 8/4/05 at 07:06 PM |
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quote:
Originally posted by alister667
The SVA testers problem was that the buckle was too high and would allow submarining and also cause injury on impact being so high - if you tightened
the should straps up the buckle could go up towards the solar plexus.
I was under the impression it was the position of the buckle / cross straps that caused submarining, ie if they're too high. I reckoned that the
(single) lower strap's job was to pull the buckle/side straps into a safer position - NOT to take bodyweight in the event of a crash/submarining.
If you want it to do that job then you need a 6 point harness - a 5 point will have you singing falsetto surely?
Having it forward means my plums aren't in serious danger. Well, no more than normal.
I don't think I could get the 5th point much closer without cutting a lump out of my Cobra 7's anyhow!
Plums - exactly why I went for the six point option not five. Without the fifth and sixth straps my lap belt had a tendency to end up too high
whatever I did (I'm only 5'7" and 9st). I think you are right in saying that the fifth and sixth straps are not there to take any of
the strain, only put the lap belt in the correct position. However remembering the above (5'7" and 9st) I could probably fairly easily slide
under the lap belt (fibreglass seats too) without the ffth and sixth straps.
Basically the six point option holds me very securely and gives me confidence in its effectiveness.
Got to say though the my harnesses are FIA approved so the fitting instructions and warning must have been well thought out.
actual instructions attached
 
Rescued attachment scan3.JPG
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givemethebighammer
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| posted on 8/4/05 at 07:11 PM |
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and the rear of the instructions:
front says not intended to act as a body restraint rear says to reinforce mounting to hold load applied in crash. Talk about covering yourself
legally.
 
Rescued attachment scan4.jpg
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paulf
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| posted on 8/4/05 at 08:45 PM |
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I am also finding the same problem with my Luke 4 points and have been wondering if I could get an add on 5th strap.
I find that doing up the lap straps tightly first helps but straps still eventually ride up.
Paul
quote:
Originally posted by David Jenkins
Tim,
I've heard of them, but can't find a link.
Anyone know of a link, or a name for a Google search?
David
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MikeR
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| posted on 8/4/05 at 09:45 PM |
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This is why i've been looking at 6 point harnesses. Also i'm trying to find some that have the adjusters on the middle near the release
instead of the end by the chassis attachment. When ever i get in someones car i always find it hard to do up the belts cause of the adjusters being
impossible to reach.
My plan was to also use expanding foam for the seat. Any ideas how i'd use a crotch strap with that?
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