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For those with 5 or 6 point harness, where do you mount them?

I am planning to take my Z to the track, but they required at least 5 point harness. I don't want to drill holes just to mount the harness. I was thinking about maybe mounting them on the seat backet bolts, would that work?

Tks in advance..
 

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2 lapbelt, 2 shoulder belt and 1 crotch belt.

you might be able to mount the lapbelts to the stock locations but not the shoulder belts.

you may need a roll bar or a harness bar for the shoulder belts. in my mcoupe i use a harness bar just for the shoulder belts.
 

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Discussion Starter #3
Tks for your reply, looks like I'll have to find a spot to mount the shoulder belts.



notE46 said:
2 lapbelt, 2 shoulder belt and 1 crotch belt.

you might be able to mount the lapbelts to the stock locations but not the shoulder belts.

you may need a roll bar or a harness bar for the shoulder belts. in my mcoupe i use a harness bar just for the shoulder belts.
 

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advantyper said:
Tks for your reply, looks like I'll have to find a spot to mount the shoulder belts.

reposted from another board


) SFI-rated harnesses are generally US made. They are generally made of Nylon, which has poor UV immunity, losing something like 80% of its strength over 3 years (of constant UV exposure). They also lose a fraction of their strength when wet, and some of that strength does not come back even after drying. They have a 2-year life.

FIA-rated harnesses are generally European made. They are made of Polyester, which has much better UV immunity. They have a 5-year life. G-Force is an exception, because it is an Nylon FIA harness and probably should be treated as if it were SFI rated.

All harness should be replaced after 10 years, even stock DOT harnesses or Schroth DOT clip-in harnesses -- sooner if worn.

2) A 30 MPH crash sled test results in about a 28g impact. Your harnesses may slip as much as 4 inches through the buckles, and the material will stretch further. Always allow at least 4" of slack at the harness tails. You WILL hit the steering wheel and the passenger WILL hit the windshield. Therefore, a full-face helmet is recommended. If you have an airbag, it will probably rip an open-face helmet off you head, leaving you unprotected.

3) Carefully observe installation instructions. The load of the attachments much be aligned with the buckle. An off-center loading will load one edge of the webbing first, and rip it out. This may have happened to Dale Earnhart. Some hardware is meant to be bent once (and only once), other hardware not at all. Stock attachment points may, or may not work. With a race seat, don't let the adjusters hang up on the seat bottom holes as it may prevent the harness from working. You may have to switch seats or harnesses to find a combination that fits together with your mounting points.

4) 2" waist belts (not 3") are preferred, will be mandated in the future for all sanctioning bodies, and are superior to 3" belts -- especially for 4-point harnesses. The goal is to load the waist belt first, before the shoulder belts. Doing so prevents the torso from sliding forward under the waist belt, injurying the liver and kidneys (possibly fatally). The 2" width fits the arch on the pelvic bone, whereas a 3" belt rides atop it. A 2" belt can usually be tightened 1-2" more than a 3" belt. Your waist belt should be absolutely as tight as you can make it.

5) NEVER run a 5-point harness in front of the seat. It must come up vertically through the seat just in front of your crotch. Its purpose is to hold down the cam so the shoulder harness don't pull it up (allowing the torso to slide underneath. A mis-installed 5-point harness may be worse than a stock 3-point harness.

6) A stock 3-point belt works by rotating the upper torso, which loads the waist belt and prevents you from slipping under. The Schroth ASM (Anti-SubMarine) 4-point harness has a rip-out section which allows the same rotation, and is better than a 3-point harness. I should not that Joe sells these, but I think his opinion is unbiased.

The Schroth clip-in harnesses use the stock pretensioner, giving you another 2" of waist belt tightening in an accident (assuming they go off).

7) Never combine a 3-point harness with a 4-point harness as your neck will be in the intersetion in a front collision. Also, the dissimilar materials may interact in an undesirable way.

8) Observe the waist belt attachment angles. The waste belt should be mostly down (up to 80 degrees from horizontal) to quickly load the waist belt.

9) Shoulder harnesses should be roughly horizontal or slightly down-tilting. Sharply down-tilting shoulder harnesses compress the spine in an impact. They MUST go between the headrest supports or through grommets (as in our stock seats) to avoid them slipping off. In a side impact, a shoulder harness that goes around the seat will come right off your shoulders. You stock seat back will deform heavily in an accident.

10) Wear a neck brace to prevent neck injuries. Adjust the headrest to the center of the helmet to prevent whiplash. (Can't in our cars, obviously.)

11) Open face helmets will be outlawed by racing bodies and should never be used in a car. There is no protection to your lower face, which can be pushed back into your brain. Again, this contributed to Dale Earnharts demise.

12) Sit-on style 6-point harnesses should only be used in a heavily reclined racing posture, such as in a formula car. There is no roll-over protection, as the straps will force you up. Protection against forward motion is provided by the inclided seat pan of the seat (which street cars don't have).

13) A 6-point harness is better than a 5-point harness for safety (not for comfort or gonad protection reasons), but I can't remember why. I think he said that NASCAR now requires them. I think it has to do with holding the waist belt down better.

14) Don't mix hardware and webbing from different makers. The exact size of the slots in the hardware is for specific webbing. You will may get excessive pull-through, and no one will have tested that combo. Remember that a maximum survivable impact might be 75g. The stress on the harnesses is extreme.

15) Replace any harnesses that have been in an impact, or any that show signs of wear, abrasion, tears, or nicks from being caught in the door.

16) SA rated helmets are designed not only for fire protection, but for impact with the internal surfaces of the car (such as roll-bar padding). M rated helmets are designed only for point impact, such as the helmet hitting the ground. I'm not sure what exactly this means from an engineering perspective, but that's what he said. BMWCCA will stop accepting M rated helmets in 2005 (when the M95 helmets expire).

17) Never wear a sternum strap as it may chop your head off when your body slides under your waist belt. Joe knows that some makers offer them, but he doesn't recommend them.
pay attention to the 5th and 6th belt.
 
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