5 or 6 point harness in an SPF?

[Neil]

OOOHH. yea, without the helmet, even a slight impact would scalp you without if I'm seeing what I think I see in that door.

Yes, in that photo, without a helmet it would not be a good idea to hit anything. Actually, cutting out the underside skin of that door was an attempt to get some clearance for the bigger SFI approved helmets. No dice, the inspectors wanted the top of my helmet to be below the top of the roll cage (reasonable), so I had to build a new seat so I sat lower and slightly more forward. In this near-prone position, a 7-point harness is desirable to keep from slipping out under it in a forward crash.

Hitting something inside the car is not the only consideration, though. I had a friend who crashed his car at 432 mph a few years ago. He was fully belted in, wearing a HANS device, and his roll cage structure did its job of protecting him but although he did not strike anything inside the car, he sustained a closed-head brain injury from just the incredible "G" forces involved in rolling & tumbling to a stop from that speed. His recovery is still on-going.

 

[Randy Folsom]

I am not sure I would want to be wearing a 7-point harness driving the streets. Beyond confining. I think you have to think about the practicality of a 6 or 7 point harness for normal driving versus a track car situation. I look at all the very high performance cars Ferrari, Lamborghini, Aston, etc. produce and none have such harnesses. A high quality 3-point is more than sufficient if installed properly. That is also why designs like the ERA GtT have a Roll Hoop but it is BEHIND the passenger firewall. The problem with kit GTs (for the most part) is the center section is just fiberglass and not a stressed steel structure like the SPF tub. I would be far more concerned about hitting something like a road barrier and having it come through the A pillars which are weak and hit me. Someone was recently killed in a cobra that way. There is little strength with that structure made of glass.

This is my first performance car and so have never worn a harness. I am hoping that I can install a six or seven point, but use it as a four point when driving around town or on the highway. Please let me know if that’s not a good plan.

You bring up a good point regarding side impact, I am thinking to weld up anti-intrusion cross bars for the doors that also beef up the door latch and hinge mounts. Then use Kevlar felt instead of fiberglass cloth to bond them to the insides of the doors. It is not expensive, so I might also line the inside of the rocker panels with kevlar felt to help protect the fuel tanks.
Cheers, Randy

 

[Markus]

Thanks Guys - all 3 ? Frank

Frank,
Yes, you made 3 posts with 3 files ....
Cheers

 

[Frank Catt]

Thanks Markus, I just hope these guys read and understand this, in this case sometimes more is far worse than less. I will NOT drive any GT40 with exposed steelwork, and pictures in my articles are REAL, Frank

 

[Randy V]

This was EGLITOM‘s car…
As I recall, he was in a coma for a couple of years before he ultimately succumbed to his injuries. Massive head trauma even though he was likely belted in tightly.

Tom was a good friend, and excellent engineer and driver. We miss him here and I won’t let his death be meaningless.
If you want a cage in your car - please use SFI padding and consider wearing a helmet, lest your family and friends go through the same nightmare that Tom’s family (and his passenger’s family) went through…

 

[Randy Folsom]

This was EGLITOM‘s car…
As I recall, he was in a coma for a couple of years before he ultimately succumbed to his injuries. Massive head trauma even though he was likely belted in tightly. View attachment 132267
Tom was a good friend, and excellent engineer and driver. We miss him here and I won’t let his death be meaningless.
If you want a cage in your car - please use SFI padding and consider wearing a helmet, lest your family and friends go through the same nightmare that Tom’s family (and his passenger’s family) went through…

Randy, Thank you for sharing. I was aware of this from reading his build log. His death is why I did not opt for the full cage, only the front and rear hoops. RCR refers to that configuration as Track Day, as it is the minimum requirement for getting on a track for some spirited driving. I do plan to use SFI approved padding. I am also only 5’7”, so that gives my head a few more inches of clearance. I am also of an age that driving fast enough to cause that kind of wreckage is simply beyond my abilities. I’ll be lucky to top 140 on the track and I am disinclined to exceed posted speed limits by more than the customary 5 or 10 mph. Thank you again for your concern and your continued efforts to keep the community informed and safe. Best, Randy

 

[Frank Catt]

Randy, did you read the articles I referred to ? Frank

 

[JP Verweij]

Randy, the front hoop without support makes it even more deathtrap.
The front hoop collapses in your face and stays there. Thats the safety issue with a GT40.
Without a front hoop its just fibreglass that collapses, the rear frame will just roll you over and keep enough space to keep you save.
A rear hoop isn't an issue.

Ive seen roll over crashes at Spa where the driver was saved by not having a cage at all.
One of those GT40's ended up at Mick Southern GT where Mick pointed out to us all the points on that Gt40 where a roll over accident will save you from major injury without a cage.

 

[Lee Patterson]

I don't even understand the concept of an unsupported front hoop.

 

[Howard Jones]

I think everybody is missing something. The angle of the seat back in a GT40. My GTD seat back is 34 degrees laid back. My F150 Ford truck is about 10 degrees. Why do I mention this? Because the laid-back nature of the usual GT40 seat makes it very likely that the body in the seat will want to slide forward from the hips typically known as "submarining". In a high-speed shunt and I MEAN ABOVE 40 mph!!!! Really! That slow! There is a tremendous amount of energy involved in a crash especially if you hit something that does not move like a tree or a concrete wall.

4 POINT HARNESSES SHOULD NEVER BE USED IN A GT40 TYPE CAR with laid-back seats! EVER!

WATCH THIS PLEASE!!!!!!!

 

[Neil]

I think everybody is missing something. The angle of the seat back in a GT40. My GTD seat back is 34 degrees laid back. My F150 Ford truck is about 10 degrees. Why do I mention this? Because the laid-back nature of the usual GT40 seat makes it very likely that the body in the seat will want to slide forward from the hips typically known as "submarining". In a high-speed shunt and I MEAN ABOVE 40 mph!!!! Really! That slow! There is a tremendous amount of energy involved in a crash especially if you hit something that does not move like a tree or a concrete wall.

4 POINT HARNESSES SHOULD NEVER BE USED IN A GT40 TYPE CAR with laid-back seats! EVER!

WATCH THIS PLEASE!!!!!!!

I generally agree with Howard- a 4-point harness is very dangerous in laid-back seats like the GT40. That's why I recommended a 7-point. Yes, it's inconvenient but it's your life, your choice. My black Mirage is laid back even more than a GT40 so I chose a 7-point harness. This one distributes the forces more evenly about your crotch area- an important consideration with laid-back seats.

That video uses rather upright seats in his illustrations so it isn't too relevant.

 

[Howard Jones]

Here is a NASA article on 7-point harnesses:

Seven Points are Better than Five - NASA Speed News Magazine

Racing harnesses meld the driver to the machine so the two can become one. The driver can use his or her arms and legs to give precise inputs into the vehicle as opposed to using those arms and legs to stay in the seat. A racing seat also can help with this process. Many NASA […]

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