Harness Mounting Points

[n4bes]

As the title suggests, I am looking 2 put harnesses into my Rx 7.

Where is the best mounting points for them....??....

Thanks all

[iaint]

I\'ve seen a lot of people mounting them off their rear strut braces and am in two minds about how wise this is...

1) For stability mounting off the strut brace will be fine, the bar will be strong enough to cope with that.

2) in the event of a prang it may well collapse as it\'s not designed to cope with forces in that direction.

3) If you crash with enough force to deform the brace then the car\'s going to be badly broken so the brace will be the least of your worries.

I came to the conclusion that if I were to fit harnesses (it\'d be for track day stability) then I\'d also wear the inertia reel seat belt for protection in a crash.

Whatever you do - if you\'re only using hte harness make sure that you find a solid enough mounting point or it\'s your life you\'re risking...

[bobert]

I have got mine on my rear strut brace

[nicksterrx7]

For what it\'s worth I\'ve been considering this and was told in no uncertain terms that the rear brace is NOT strong enough and should not be used as a mounting point.  There used to be a kit that bolted behind the seats but apparently the manufacturer no longer makes this (Chris at REWORX told me some time ago).  If you do find out, let me know plaese.

[TonyC]

Often the easiest place is to use the same moutning areas the inertia belts are attahced to - IE: remove the bolts holding in the inertia belts and repalce with the eye bolt of rthe harness. You must be careful not to have the rear should straps at too acute an angle though. When I was looking at the stripped shel of my car there appears to be threaded plates under the rear seats (presumably for rear seat belts?) - I would screw the eye bolts into these areas. You ideally want the eye bolts working in sheer, not traction - IE: an impact would try and snap the bolt in tow, rather than pull it out through the threads.
I wouldn\'t use a strut bar for the harness mounitng.

[RemarkLima]

Good to hear that the rear strut brace isn\'t strong enough... Been thinking about this myself...

I was looking at:
http://www.mazdarotaryclub.com/forums/showthread.php?t=29241 but I\'m still undecided about the strength...

Now, what I am thinking, is mount eyes onto the rear seat belt mounts into the chassis, as this would definately be strong enough, then swing the harness\' over the brace to get them straight to the back of the seat... It would mean in a crash that the brace would still deform, but at least the harness\' would still be attached... Plus it may help absorb the impact a little as I know it hurts like fduk when nothing moves except your head

[TonyC]

I wouldn\'t swing them over the brace, let them have a straight run up to the seat and shoulders.

[iaint]

I wouldn\'t swing them over the brace, let them have a straight run up to the seat and shoulders.

Angle would be wrong though.  The shoulder part of the harness should be pulling you backwards not downwards.

[J4P RX]

Angle would be wrong though.  The shoulder part of the harness should be pulling you backwards not downwards.

Thats exatly what its meant to do.  Shoulder harness ideally wouldnt pull down at all (only backwards) and would run at a right angle out of the seat.

[RemarkLima]

That\'s right, I\'ll dig out my blue book and check but really shoulder harness\' want to go straight back, which is often difficult but as straight as possible is best... I guess the boot floor would be OK, but again depends how thick it is... In a big accident you\'d want something else to peel away / buckle however as if you\'re 100% fixed without a HANS device you\'d be more likely to break your neck.

[TonyC]

Bluebook will give you a degree of angle that is acceptable. It doesn\'t have to be 100% straight across your shoulders and down - using the far rear seat belt mounts should be ok.
I wouldn\'t swing it over the strut brace to get the straight angle becuase it:
a) puts unusual load on the belt (mid way down the webbing that is slung over the strut brace rather than in the full length of the webbing as it is taut)
b) should the strut brace deform or buckle (and it could easily do so in a big shunt) then the harness will suddenly find itself with an extra few inches to move before it holds you in the chair - IE: you will pull the harness tight on your shoulder with the tension over the strut brace - as soon as that tension is relieved due to the brace deforming or coming loose then the shoulder harness will be slack and you are going to start to flap around inside the seat. Not a good idea.

[RemarkLima]

Mmm, good point there... Things are so much easier with a cage

[TonyC]

Aye, you should see the size of the one in the RX I\'ve just bought! And it still needs a couple of extra braces! A harness bar running across the rear cage uprights is a different kettle of fish to a strut brace.

[RemarkLima]

Exactly! I was going to say earlier the harness bar\'s make life easier (as well as the cage stiffer!).

But as I\'d like to keep this as a road car (don\'t htink my gf will appreciate having 2 cars stripped out and caged! LOL!) it looks like the rear seat belt mounts would be the best bet?

[TonyC]

My initial inspection of the car suggested they will be ok - I need to pick mine up and really start the prep yet though - I used similar mountings on my previous race car and they passed scrutineering, etc fine for 3 years with no remarks or worries.