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      07-12-2020, 12:18 PM   #1
AWC-F87
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Safe cage install

What's up guys!

I'm quest for speed and safety I've come to a speed bump.

I purchased a bolt in cage from someone. I won't name the cage or the person cause they've done nothing wrong. I didn't do my HW first.

The cage basically just bolts to the floor pan behind the front seats. If you know our cars you know that metal is thin AF.

I want the cage for proper mounting of harness's and for some added roll over safety.

I want your opinions from people who have properly caged our cars about where to tie in a 4pt cage properly and safely.

Thanks
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      07-13-2020, 02:29 AM   #2
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Quote:
Originally Posted by AWC-F87 View Post
What's up guys!

I'm quest for speed and safety I've come to a speed bump.

I purchased a bolt in cage from someone. I won't name the cage or the person cause they've done nothing wrong. I didn't do my HW first.

The cage basically just bolts to the floor pan behind the front seats. If you know our cars you know that metal is thin AF.

I want the cage for proper mounting of harness's and for some added roll over safety.

I want your opinions from people who have properly caged our cars about where to tie in a 4pt cage properly and safely.

Thanks
Not many people build thier own roll bars. Most buy off the shelf. If you want something that custom and HC talk to a cage builder and they will steer you in the right direction.

Most bolt in rollbars tie into the seatbelt mounting points or nearby.

The thiness of the metal is not necessarilly an issue so long as the load is sufficiently spread out (with backing plates if necessary). Also could be a part of the body made with very high strength steel (for example).

See the Weichers design for example that uses plates screwed to the seat mounting points in order to spread the load and lower the bar legs (it can be optioned with a harness bar).

https://www.facebook.com/tmmotorspor...3124698835944/

or which goes in the kick up for the fuel tank (geometrically strong) and near the rear craddle mounting (also strong).

https://www.facebook.com/AlphaNPerfo...0524996072945/

The good thing about German designs are that they need to have a TUV aproval that gives some sort of safety quality control.

Edit: also a good design http://shop.mkr-engineering.de/Clubsportbuegel_BMW_M2
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      07-13-2020, 07:59 AM   #3
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Roll Bar/Cage

Quote:
Originally Posted by AWC-F87 View Post
What's up guys!

I'm quest for speed and safety I've come to a speed bump.

I purchased a bolt in cage from someone. I won't name the cage or the person cause they've done nothing wrong. I didn't do my HW first.

The cage basically just bolts to the floor pan behind the front seats. If you know our cars you know that metal is thin AF.

I want the cage for proper mounting of harness's and for some added roll over safety.

I want your opinions from people who have proThe one thing holding perly caged our cars about where to tie in a 4pt cage properly and safely.

Thanks
I have been trying to decide which cage to go with as there seems to be only 2 that I know of. I have been leaning towards Ind/Fall Line. They have photos of one being installed in a M2. It seems to be securely bolted in front of the riser of the back seat, and the Shock Tower in the rear. The one thing holding me back is the total cost consisting of Seats, Roll Bar, Rear Enclosure, Harnesses, and Coding Out nannies. Don't know if I want to push my car over the DD/Track Car cliff.
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      07-13-2020, 08:43 AM   #4
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Whatever you end up with make sure there is no conceivable way your head could hit it if you get in an accident on the street. Running a cage with no helmet on will kill you if there's contact. BSCI padding likely isn't going to save your noggin if it hits w/o helmet.
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      07-13-2020, 09:25 PM   #5
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I dont think the falline one is made anymore.

I really like the one that mounts to the rigid metal of the back seat tub. That would also be easy to make myself.

I will absolutely make sure my head is clear for street driving.

Thanks guys! Would love to see more options and opinions about this. There is a lot of bad design cages out there.
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      07-13-2020, 09:38 PM   #6
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Quote:
Originally Posted by AWC-F87 View Post
I dont think the falline one is made anymore.

I really like the one that mounts to the rigid metal of the back seat tub. That would also be easy to make myself.

I will absolutely make sure my head is clear for street driving.

Thanks guys! Would love to see more options and opinions about this. There is a lot of bad design cages out there.
The Fall Line one is still available as I have a quote from IND for it. Trying to decide which way to go with Nogaro Track seats. Might end up just going with a harness bar in back.
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      07-15-2020, 11:43 PM   #7
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Quote:
Originally Posted by chief1richard View Post
Quote:
Originally Posted by AWC-F87 View Post
I dont think the falline one is made anymore.

I really like the one that mounts to the rigid metal of the back seat tub. That would also be easy to make myself.

I will absolutely make sure my head is clear for street driving.

Thanks guys! Would love to see more options and opinions about this. There is a lot of bad design cages out there.
The Fall Line one is still available as I have a quote from IND for it. Trying to decide which way to go with Nogaro Track seats. Might end up just going with a harness bar in back.
Yeah you're right. I was thinking about the other one listed on their site but it says no longer available. I don't like how the fall line mounts to the floor pan. I'm trying to get away from that. I think it's wrong and not structurally safe.
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      07-16-2020, 08:13 PM   #8
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If you are on a quest for safety then I would ditch the 4 point harnesses and get a 5 or 6 point instead.
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      07-17-2020, 12:53 AM   #9
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Quote:
Originally Posted by kpaso View Post
If you are on a quest for safety then I would ditch the 4 point harnesses and get a 5 or 6 point instead.
I haven't purchased harnesses yet. I am open to suggestions for 5 Points.
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      07-17-2020, 12:44 PM   #10
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Quote:
Originally Posted by AWC-F87 View Post
Quote:
Originally Posted by kpaso View Post
If you are on a quest for safety then I would ditch the 4 point harnesses and get a 5 or 6 point instead.
I haven't purchased harnesses yet. I am open to suggestions for 5 Points.
Go 6, it'll be more comfortable! Also, I'd get a 2" vs 3", and pull down waist instead of pull up. All the brands are comparable assuming like hardware, sizing, etc.
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      07-18-2020, 06:27 PM   #11
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Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by AWC-F87 View Post
Quote:
Originally Posted by kpaso View Post
If you are on a quest for safety then I would ditch the 4 point harnesses and get a 5 or 6 point instead.
I haven't purchased harnesses yet. I am open to suggestions for 5 Points.
Go 6, it'll be more comfortable! Also, I'd get a 2" vs 3", and pull down waist instead of pull up. All the brands are comparable assuming like hardware, sizing, etc.
Thank you! I appreciate that insight!
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