Where to drill bottom harness holes 4point

I have a mk 2.5 sport and have fitted a T R Lane RB with welded in harness bar so top fixings for my 4 point harness will be wrap round. Sorted.

 

I will be using some cloth seats as they have slide in head restraints and I’ve performed a “foamectomy” on the drivers one so I fit when wearing a helmet.

 

The one remaining thing is to drill/weld the bottom two (4 if I do the passenger side) harness fixings.

Any advice on position etc ? Angle the belt should be ?  A photo through the open door would be good.

 

Any help would be appreciated,

Paul G

 

p…s. I would like the existing seat belts with their clasp on the side of the seat to remain for road use.

 

This might be of some use? Just one bit of info

https://www.hmsmotorsport.com/docs/Takata_Tuning_Instructions.pdf

There is a load of info on a Google search, videos etc. Maybe not model specific for your car but general principles apply. On my mk1, I utilised the OEM lower fixing points for the anchorages, at the same time retaining the OEM belts. New eye bolts were purchased, they are standard 7/16th UNF and clip in fixings for the lower harness. Fortunately, on the early mk1’s, the inner seatbelt fixings are a captive nut on the transmission tunnel, so easy to do. Not sure your inner ones are like that? Probably on the seat frame? A spreader plate will be needed, welded to the underside of the transmission tunnel, hole drilled through tunnel to align with captive nut on spreader plate and away you go. Position wise, directly opposite the OEM outer fixing point, or as near as will allow. People like demon tweeks sell the range of fixings/ plates etc 

Barrie

 

 

Cheers for that Barrie.

The belts I have connect into a central rotating clasp so the upper ones will be diagonal, Shoulder to belly button for want of a better description.

I’m guessing bottom ones go on to the transmission tunnel one side and welded on the side of the inner sill the other ???

It would be easier if to the floor as I could get to the other side to weld the plate to the underside of the car. Don’t know if this is OK.

The 60 to 80 angle  was useful.

 

Cheers 

Paul G

 

 

 

 

Looking into things a bit deeper I find that the sill side couldn’t be easier.

The original belt mount with a little playing around with spacers and washers will take both belts.

The transition tunnel side will require a drilled hole, spreader plate and welded on nut however.

But hey, thats three mount points sorted and just one to go.

 

Paul G

 

Sounds like it’s all coming together nicely 

Barrie

Check that transmission tunnel. There may be an unused hole with a plastic plug. This is the location of the tapped hole used on early MX5 seatbelt latches. The same part, with a light modification was carried over into the NBs. There’s no captive nut anymore (I think) though.

The blanking plug is visible on this stripped 2004:

Hi Saz

 

If you mean the bottom right in your photo then that is passenger side only and on my car it has a grommet and the wire to the rear lambda going through it.

 

I managed to drill a hole and weld the nut & plate on.  Job done.

 

Thanks for the help,

Paul G