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      10-27-2012, 04:58 PM   #1
Kgolf31
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4 Point Harness w/out Harness Bar?

Is there any mounting bolts that we can secure a 4-point harness to for Auto-x? A local was showing me his harness mounting bolt in his GT3 that he discovered and I didn't know if there was anything similar.
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      12-01-2012, 11:43 PM   #2
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I don't think there's such a mounting point for the Z4s. Maybe the child safety lock points on the passenger side might suffice, but it'd be kinda risky I think. Better to get an actual bar at the very least, if not a half to a full cage.
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      12-02-2012, 09:50 AM   #3
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funny.... i was wondering this same thing.... i saw a 1M at my local event and he fitted some bolt down eyelets to the seat mount points and attached them their... im not sure if this is legal or not.
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      12-02-2012, 03:16 PM   #4
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Quote:
Originally Posted by Beedub View Post
funny.... i was wondering this same thing.... i saw a 1M at my local event and he fitted some bolt down eyelets to the seat mount points and attached them their... im not sure if this is legal or not.
If we had back seats, we could potentially use the rear seatbelt receptacles as some form of mounting
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      12-02-2012, 03:17 PM   #5
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From what I understand you should only run a 4-point if you have a cage.

Otherwise in a roll-over the 4 point will keep you upright into to the collapsing roof/windshield. The hack went into it a bit here.
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      12-02-2012, 03:26 PM   #6
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Quote:
Originally Posted by mfanatic325 View Post
If we had back seats, we could potentially use the rear seatbelt receptacles as some form of mounting

no no no.... his bolted straight down to the floor, they looped over the tops of the seats and was bolted down to where the runners are bolted to the floor..... like i say, i have no idea if this is sufficient in terms of safety.
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      12-02-2012, 03:38 PM   #7
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Quote:
Originally Posted by Beedub View Post
no no no.... his bolted straight down to the floor, they looped over the tops of the seats and was bolted down to where the runners are bolted to the floor..... like i say, i have no idea if this is sufficient in terms of safety.
Yea, that's a no-go.

You need to maintain a certain angle in relation to the seat for the straps behind the seats
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      12-03-2012, 12:57 AM   #8
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Quote:
Originally Posted by Kgolf31 View Post
Yea, that's a no-go.

You need to maintain a certain angle in relation to the seat for the straps behind the seats
Yup, the two shoulder straps cannot pull downwards on you.
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      12-03-2012, 04:36 AM   #9
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how much does a harness bar typically cost? a half cage?
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      12-03-2012, 11:21 AM   #10
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The main reason I asked this, is that I need to maintain class rules for SCCA Solo.
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      12-03-2012, 01:13 PM   #11
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Quote:
Originally Posted by 007MCoupe View Post
how much does a harness bar typically cost? a half cage?
For a custom harness bar only, you're looking at upwards of $350 for materials and labor. If you want a half cage, that'll probably bump up to $500. And for full cage, depending on bolt in or weld in, I wouldn't be surprised if it went all the way up to $1,500 or more; as there's lots of labor involved.
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      12-04-2012, 04:26 AM   #12
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Hmm I newer looked into this so spare me some slack if this is a retarded idea, but couldn't you just get a rear strut bar and mount the harness there? Or is the rear strut bar not strong enough for that?

Can't find any Z4M rear strut bar, but what I mean is smth like this:
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      12-04-2012, 05:01 AM   #13
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I suppose that might actually suffice as a shoulder strap bar. However, one would need to strip out everything behind the seats in order to get at the bar. Also, there's still the issue of the angle of the shoulder straps to where it's actually wrapped around/mounted. But interesting thought process there. I've never thought of using a rear strut bar for such a purpose
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      12-04-2012, 11:54 AM   #14
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I believe a full roll cage, or partial roll cage/bar is permitted in any class of SCCA autocross.
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      12-04-2012, 01:15 PM   #15
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Quote:
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I believe a full roll cage, or partial roll cage/bar is permitted in any class of SCCA autocross.
I will have to check, but I'm almost positive not.

You increase the stiffness of the chassis.
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      12-04-2012, 01:49 PM   #16
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From the rulebook:
3.3.2 Roll Bars
Roll bars or roll cages are strongly recommended in all cars.
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