What is the best way to adjust a four point harness and where should the clips sit in relation to your shoulder.

The reason I ask is that in my CS the rears are secured to the eyelets in the area of the rear seat, but by the time they go up and over the KLA bar between the C pillars they seem to be on the edge of there adjustment. This means that the adjusters on my shoulder straps are sitting just under my collar bones. If you look at the photos on my site you'll see what I mean about the position of the harness bar. Click here and then the photos button, harness bar pic is at the bottom of the page

Is there a better posistion to secure the rear eyes ? Is the KLA bar any good or should I ditch it and go without ?


Cheers

Mike

 

before everyone else here jumps on you about this....

nice belts, probably an OK bar but harnesses don't work without the sub-strap to hold the lap belt down, the angles on the shoulder belts look wrong and you absolutely can not use harnesses without a guide bar. In a crash as your weight is thrown forward the belts will compress your spine causing severe injury. Please have your install looked at by someone that is familiar with safety equipment instillation, I would not drive the car as it is set up.

best

drive safe

 

I don't disagree that a sub-strap is a good option but if they do not work without one why do these companies produce 3 & 4 point clubman harnesses at all, especially this belt as it is E-marked i.e. road legal.

Secondly, taking on board the sub belt comment, but moving onto the mounting issue is it as I already suspect that the rear fixings need to be up on the rear cargo floor area ? If so has anyone done this successfully without the need for a cage ?

Thanks

Mike


P.S. I still have the OE belts in place so I can still drive it with these for now.

 

I agree with Al. 4 points can be very dangerous. Some claim to be designed as 4 points, but I would not risk my life on them. As far as the harness bar - I think you have a problem with that. As I recall, these are not supposed to have the belts 'bend' more than ~90 degrees - a 180 wrap will double the force on the bar and that is bad. It has been a while since I looked at harness bars, so I might well be wrong, but you should take a close look at the specs on your bar to make sure.

 

no clue, I think however the term "Clubman" gives it away. where as no race sanctioning body would approve 4 points the manufacturers seem to think that a person doing a club event such as Drivers Ed. doesn't need as much safety as a racer. It doesn't matter wether you are in a race or just lapping at a track with a club if you have a shunt and hit something it's going to hurt. As far as E-marked or DOT approved I again have no idea as to what criteria they are tested. In the US most harness systems are not DOT approved for street use becuse of a lack of UV protection or the testing there of.

Again I'm not trying to jump on your install but I'd rather see you be safe.

drive safe
have fun
go fast

 

I am pretty sure that DOT 'approval' simply means certain standards were met in regards to materials, buckles, etc and does not include crash testing. I think the idea of these 4 points is that the sholder straps stretch in such a way that the lap belt does not ride up. The problem I have is that 3 points are extensively tested and there is lots of data on 5/6/7 point belts. 4 points have very little data and I don't risk my life on such things. Even a sub strap that goes in front of the seat is going to help stabilize the lap belts, IMO.

 

So would I Al hence the questions Feel free to jump on the install I'd like my head to remain fixed to my body.

Mike

 

I tried unsucessfully to get a dialogue going on these 4-points. I know what I think, and what I have been able to find out from manufacturer sites. But was interested to see what the cumulative knowledge might turn up. Until this thread, not much.

I find only one manufacturer (who also has an excellent rep for other items). Mention of 'certification' but no mention of any crash data or testing. Absent some kind of data it is really hard to believe these units do not suffer from the soft tissue damage concern with the lap belt riding up. And, some of the shoulder harness attachments recommended fly in the face of our usual guidelines regarding compression. Not to mention the worlds longest webbing runs. (Even if it is webbing that stretches less).

Apparently they are used a lot in Europe? And on this side of the pond for autocross.

 

John

Check the archives. This has been discussed ad nauseum.

Richard

 

Hi Mike;

I really don't have ANYTHING good to say about your setup. Well, Willans is certainly a long respected name in safety equipment, but other than that everything flies in the face of what we hold as a standard setup.

Issues;

- 4-point. John no like!

- Long belt travel. Too much stretch in the fabric = too much travel of your body = you come completely out of the seat, whip around, and probably also BIFF something.

- Belt angles coming forward are all wrong. You need some amount of downward angle from the shoulder to the mount/guide point. This creates enough compression to firmly hold you under the shoulder straps, but not enough to create too much spinal compression.

- Not sure about the foam on the harness bar. Perhaps to keep the belts from sliding laterally? If it's not glued on, it will just slip off, most likely.

- The belt bar itself looks pretty spindly to me. Consider how much force is involved in a body moving against the belts. MANY MANY hundreds of pounds. If I remember correctly - and I may be wrong here - I think I recall the standard as being some-number-of-thousands-of-pounds to failure? I don't see that little thing taking that.

- Your seat angle seems awfully slack, which does not help your belt angles at all. Fortunately the seat base does offer quite a bit of "cupping" of your bum to help keep you in the seat. Otherwise, it would be a fright.

Not trying to be a downer, mate. Beautiful machine! We on this side of the pond are jealous of your opportunity to own these lovelies.

 

So basicly the KLA guide bar is a total lemon, how do they getaway selling it are there no regulations to stop this sort of marketing ?

Would I be better running without the bar and connecting directly to the lower rear seat belt mounts given that the seats are slotted and should prevent any movement of the shoulder straps.

As for the seat angle what do you mean I don't understand.

Thanks for the feedback its exactly the sort of stuff I need even if it isn't exactly good news.

Mike

 

Hey mike;

I am not in any way trying to dump on KLA. I do not know if their product is tested, and if so to what specs.

I am only looking at your pictures, and from what I can tell the bar is very small in diameter. I am not a scientist by any means, but there is a great amount of structural strength to be gained by cross sectional size. A fairly thin wall tube grows markedly in strength as its cross section increases. Even if a bar/tube of small diameter is extremely thick wall, or even solid, it will not have the strength required to do the job.

That item looks like a throw back to the days when people were using all manner of products that were later found to simply not be up to the task. Those days are gone. When someone really started applying real world thinking and eventually crash test dynamic loads to these items, they were found to be a miserable failure for their intended purpose. Witness the early Brey Krause designs -vs- their latest offerings.

These old timers certainly seem solid to the touch, but when you subject them to the many hundreds (if not thousands!) of pounds of force that a human body can generate in a crash, they just don't cut it.

As for the seat angle, I mention that in reference to the belt angles. Your seat back is extremely reclined. This lowers the pass-through holes quite a bit relative the the height of the harness guide bar, and therefore changes the angle of the belts as they pass through the seat. You ideally want the belts to run as straight as possible from their mount to the body, and do not want any major encumbrances or changes of path. This is absolutely most important in the lateral sense (side to side) where you want NO change of direction whatsoever, but to some extent is also important in the linear sense (front to back).

Your belts take quite a circuitous path to reach you, and that is never ideal. your mount point is in front of the bar, and as such would put a TREMENDOUS strain on the bar because of the geometry of your setup. Compound leverage would be the term I'd guess, like a block & tackle.

The idea is to keep the belt strung as close to straight as possible so that the forces are acting in a linear fashion instead of compound. Most guide bar situations compromise this to some degree, and also tend to give excessively long belt lengths.

The best solution is having the belts mounted directly to a proper MOUNT BAR.

Let me go into this further later, if you'd like. Now it's time to go out mountain biking and enjoy this beautiful Spring day! Cheers!

 

Thanks John, the seats are standard club sport fitment (Recaro Pole posistion IIRC) there is no real adjustment on them for the recline, other than I could lift the rear on its side mounts, but then with me being 6'3" tall I'd never get in with my helmet on.

I think the answer is going to be to ditch all this kit on Ebay and start again with a half cage and a better quality harness.

Mike

 

Mike;

Try these links for products that look well engineered. At least better than what you have now.

http://www.bkauto.com/porsche/r1020.php

Don Ehinger

 

Mike, don't want a penalty for "piling on", but also check to see if your seats have a cut-out in the bottom for a sub belt. Generally the sub-belt should be close to vertical from the harness buckle. I see people run the sub belt up over the front of the seat cushion and back, (done it myself) but personally, I don't believe that is very effective.... although it is probably better than nothing.

Also, don't rely on the seat cutouts to support the shoulder harnesses... the load should go directly back to a structural support.... cage, or at least an engineered truss bar.

Simpson cam lock 5-points are about $150 a set... not that expensive.