[kaiv]

I've searched and found a couple of interesting threads about which 6 point harness to get and whatnot but not a lot of info about the actual installation.

My setup: Kirk Roll Bar and Status fixed back seats.

The seats are mounted on VAC floor mounts with Momo alumium side mounts. I have a universal Sparco slider on the driver side.

So,

*Shoulder belts go on the roll bar. Ok got that.

*What about lap belts? I've seen delirium 45's setup (click). Is that the way to go?

*And the anti-submarine belts? VAC makes a bracket (click)

Is that all, anything I'm missing? Any advice/input?

Thanks in advance

[MrLiou168]

I've seen a ton of horribly installed 5 and 6-point setups, some even in students' cars where I refused to get into. You are correct with regard to the shoulder belts, and the above setup will work great.

However, installation and placement of the anti-sub belts is what concerns me the most, and the best setups I've seen are the ones where the driver is sitting on the belts. (not a typo - I mean SITTING on the belts) This means that the mounting points should be placed as far back as possible.

If you want more info, look at the setups used in both NASCAR and F1!

Hope this helps.

[nolocontendere]

VAC also makes a lap belt mounting kit that's only about $40 that you need unless you want to anchor your lap belt to the chassis. It's on their website. They are small brackets that install using the two existing rear screws for the main seat brackets themselves.

[docwyte]

The problem with mounting the sub and lap belts to the VAC plates is if the plate comes loose in a crash, the whole arrangement fails. You're much better off drilling through the floor of the car, reinforcing with a plate and mounting the sub straps behind the hole in the seat.

Also do the same thing for the inner lap belt mount, you can use the factory threaded hole for the outer lap belt mount.

[jrf m3]

I used the plates provided by schroth for my sub straps and drilled through the floor. I adhered to the strap angles suggested in the schroth instructions.

My outboard lap belt is to the oem seatbelt b pillar mount

My inboard lap belt is to my seat base using a breykrause device and grade 8 hardware - I have to agree with Docwyte however that the best mount is to the tunnel using a backing plate and this is on my to do list

if everything is attached to the seat base and that fails you are in big trouble

[delirium45]

the rear seat mounting point is crash tested by BMW and is considered an over engineered solution for mounting a seat... i would trust that before i trust any hole in the sheet metal for the lap belts, which is why i used the rear mounts.

as for the sub mounts, i used the reinforcement kits from HMS, this spreads the load over a 2"x4" area (for each mount). i think this is enough to hold my man-parts in place and keep me from sliding under the steering wheel.


i have recently stripped the interior of the car and had a lot of time spent fumbling around inside the car and working with the sheet metal there within and i am still confident that this setup is ideal for me.

VAC developed their sub bracket because a lot of customers don't want to drill holes into the body of their cars, completely understandable, however, my car was always on a one-way path and i didn't mind.

as you can see from this recent photo during the sound deadening removal the rear seat attachement points are heavily reinforced, the support structure is that whole rear bar, just like the front.


i still recommend the rear points for laps and either the VAC piece for subs or reinforced plates through the body for subs

[tjpatte]

Kaiv,

Would like to check your setup sometime, I live in Lakeside.

Doc is right about the belts, from what I remember, it's preferred that the anti-submarine belt be attached on the same plane as the waist straps. There is quite a bit of info on this over at Corner-Carvers.

One thing I'm interested in is what the rollbar plates mount to and if there is any reinforcement in that area. Not sure if the folks here have seen the pictures of the Mustang that flipped and the mounting pads for the rollbar punched through the floor pan of the car. Of course I found out about this after I had installed a rollbar in my mustang Since I plan to stick one in the M3 I need to figure out if any structural mods will need to be done.

Tom

[delirium45]

from what i've *heard* that Mustang was built with almost no attention to safety and that rollbar that was used was not designed very well. but i can totally see a rollbar punching through if you pancake the roof.

i'd like to see if the rollbar was only two point or four point and where the rear points were attached to as it looked like it just poked straight through.

[tjpatte]

77 Ford Fairmount design

It was a four point and the rear supports mounted to the rear wheel humps. It was an Autopower rollbar, I think, which is one of the better brands out there. Maximum Motorsports makes one for the newer Mustangs that the forward downtubes mount to brackets that are supported by the bottom door jamb and frame. The real problem was/is that floorpans are not really designed to withstand the pointed pressure that even 6x6" pads exert in a violent rollover. I think alot of the floorpans are only about 1/32 to 1/16 inch steel to begin with.

Just picked up my M3 about two months ago and still learning about it.

Tom

[docwyte]

It was an Autopower rollbar, bolted in using the reinforcement plates supplied. Basically the same as all the other 4 point, bolt in rollbars (Kirk, TC Designs, B'Haus, etc).

Given enough force, they'll ALL punch through, as they're mounted to single sided steel on the floor and wheel wells, which is very weak.

That's why my rollbar is welded into place with large plates/gussets and attached to the triple walled frame rails of the car...

This is one of the main reasons I sold my M3, I wasn't willing to do that sort of rollbar installation in it and anything else is total garbage.