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      02-11-2020, 04:39 AM   #1
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DIY: Schroth Harness Install

Helped a buddy install a Schroth Quick Fit Harness in his E46 and made a DIY video:

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      02-12-2020, 12:14 PM   #2
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Super dangerous to be running those harnesses with those seats. The quick fits are only approved (with good reason) for use with the stock seats and Cobra Nogaros. Traditional fixed back bucks are not designed or tested for the downward force than the quickfits place upon them. Schroth will 100% agree with this if he asks them

He could recreate the same functionality with something like the Schroth Profi II ASM (another anti submarining 4 point) mount to a roll bar, harness bar, or something like the Brey Krause rear deck harness mounts.

But, yeah... very unsafe setup in that video.
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      02-12-2020, 12:21 PM   #3
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Quote:
Originally Posted by Obioban View Post
Super dangerous to be running those harnesses with those seats. The quick fits are only approved (with good reason) for use with the stock seats and Cobra Nogaros. Traditional fixed back bucks are not designed or tested for the downward force than the quickfits place upon them. Schroth will 100% agree with this if he asks them

He could recreate the same functionality with something like the Schroth Profi II ASM (another anti submarining 4 point) mount to a roll bar, harness bar, or something like the Brey Krause rear deck harness mounts.

But, yeah... very unsafe setup in that video.
Interesting... I'll let him know! I know his plan is to put a full cage in before long.
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      02-12-2020, 02:37 PM   #4
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Quote:
Originally Posted by TTGator View Post
Interesting... I'll let him know! I know his plan is to put a full cage in before long.
Cages are super dangerous on the street, if he plans to keep street driving the car (even if it's just to/from the track).

https://www.ecstuning.com/b-brey_kra...ar/r-1246~brk/
^might be a better solution. Wouldn't make the car a death trap when not wearing a helmet.
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      02-12-2020, 02:58 PM   #5
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From what Iíve read and common sense tells me, the only time a Roll Cage or Proper belts aren't better than none is when they are improperly used. If the cage is built right and youíre not going to hit your head on it because itís correct and the harness is going to keep you from it, that setup even without a helmet is better than your stock car with stock belts in a bad crash.
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      02-12-2020, 03:22 PM   #6
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Quote:
Originally Posted by TTGator View Post
From what I’ve read and common sense tells me, the only time a Roll Cage or Proper belts aren't better than none is when they are improperly used. If the cage is built right and you’re not going to hit your head on it because it’s correct and the harness is going to keep you from it, that setup even without a helmet is better than your stock car with stock belts in a bad crash.
In a crash, if you're short enough that you can position yourself such that you'll never have head to cage contact (which is only possible with a harness, not a 3 point), with a 5/6 point, yes.

Buuuuuut... you're more likely to get into a crash in the first place wearing a harness than a 3 point, as they severely limit your ability look around, position your head, etc. Additionally, running a cage means you lose the function of the head protection airbags that curtain the windows from your head. Not a big deal if you're wearing a helmet, but not amazing if you're not.

Also, the way Schroth's 4 point anti submarining harness functions is that one of the shoulder belts expands in a crash, allowing you to twist over the seat belt like you do with a 3 point, instead of sliding under the harness like you would in a normal 4 point without a sub strap. This stretch would likely also allow head to roll cage contract.

Also, related side note: If he's not running stock seats, why is he running a 4 point harness? The benefit of schroth's 4 point anti submarining harnesses is that they can be used with seats without a sub strap pass through hole. They function, but not as well as a proper 6 point. Since he's running seats with a sub strap pass through hole, why not get a sub strap? No compromise needed, now...
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      02-12-2020, 03:29 PM   #7
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Quote:
Originally Posted by Obioban View Post
Quote:
Originally Posted by TTGator View Post
From what I’ve read and common sense tells me, the only time a Roll Cage or Proper belts aren't better than none is when they are improperly used. If the cage is built right and you’re not going to hit your head on it because it’s correct and the harness is going to keep you from it, that setup even without a helmet is better than your stock car with stock belts in a bad crash.
In a crash, if you're short enough that you can position yourself such that you'll never have head to cage contact (which is only possible with a harness, not a 3 point), with a 5/6 point, yes.

Buuuuuut... you're more likely to get into a crash in the first place wearing a harness than a 3 point, as they severely limit your ability look around, position your head, etc.

Also, the way Schroth's 4 point anti submarining harness functions is that one of the shoulder belts expands in a crash, allowing you to twist over the seat belt like you do with a 3 point, instead of sliding under the harness like you would in a normal 4 point without a sub strap. This stretch would likely also allow head to roll cage contract.

Also, related side note: If he's not running stock seats, why is he running a 4 point harness? The benefit of schroth's 4 point anti submarining harnesses is that they can be used with seats without a sub strap pass through hole. They function, but not as well as a proper 6 point. Since he's running seats with a sub strap pass through hole, why not get a sub strap? No compromise needed, now...
All excellent info! I'm really new to the whole cage/harness/etc convo and I'm loving learning!

His response when I told him your initial safety concern was "Yea. I know about the fix back seats without a harness bar or half cage. It's the downward force on your shoulders since the pivot point is below your shoulders. It's just the best option now before I get a half cage. Dot approved harnesses usually have an extra fold that's stitched that will break and have a little bit of release in the event of a crash. It's just the best option now before I get a half cage. Dot approved harnesses usually have an extra fold that's stitched that will break and have a little bit of release in the event of a crash."

I'll show him your suggestion!
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