View Single Post
Old 27th February 2021, 19:15
peterux's Avatar
peterux peterux is online now
Senior Member
Join Date: Mar 2005
Posts: 2,939
peterux is on a distinguished road
Default Belted up.............

Thanks Amir and Mr. Towed.
This week I've addressed a long standing issue that I've been aware off ever since I first got my Sabre.
As I said above, my car is a very early one manufactured in 1994, well before the SVA now replaced by the IVA test.
This is the diagram from the IVA manual that shows how to check the height of the upper anchorage point for the seat belts. The minimum height from the reference point 'R' is 450mm in the text. And as you can see the seat type and mounting height is also important.

IVA seatbelt height by Sabrebuilder, on Flickr

This is the view of the Sabre's upper anchorage point as designed in 1994. The upright is welded to the chassis. The diagonal brace takes the seat belt upper mounting and the hood frame.

Hood frame and rear brace by Sabrebuilder, on Flickr

On later Sabre's the seat belt mounting point is welded into the top of the vertical 'B' post. The post is longer making this point higher and the post is mounted more inboard so the diagonal is flat and bolted to the outside edge of the post.
Photo courtesy of Stewart Arnott
Later Sabre chassis by Sabrebuilder, on Flickr

I could have had the chassis reworked as this type of welding was way beyond my capability. Instead, I've raised the seatbelt mounting by welding a small plate to the diagonal and re-drilling the mounting hole in this plate. (The folding hood frame will need to be modified but that shouldn't be too difficult.) The plate is the same thickness as the original diagonal brace and I welded it on both sides to make it as strong as possible. In an accident, the weld will be mostly under compression.
I also plan to rework the interior trim so that it covers the diagonal upper edge.

Modified seatbelt diagonal by Sabrebuilder, on Flickr

The IVA examiners have a special measurement tool with string and spirit levels. I improvised with a piece of timber mounted between the seatbelts. The top surface of the timber is the 'effective anchorage point'.

Seatbelt height measurement by Sabrebuilder, on Flickr

I made up the IVA specified 'distance piece' from a cereal carton. The cross section is exactly 136mm x 53mm

IVA distance piece by Sabrebuilder, on Flickr

I then clamped a steel rule to the timber and used my magnetic spirit level to make sure the steel rule was level.

Seatbelt height measurement by Sabrebuilder, on Flickr

I could then measure from the reference point to the horizontal steel rule.

Seatbelt height measurement by Sabrebuilder, on Flickr

Seatbelt height measurement by Sabrebuilder, on Flickr

My measurement comes out at 468mm so hopefully I have about 18mm 'contingency' for measurement error.

So, I think I've cracked this issue but if anyone can see a flaw in my solution please shout out as I'd rather know now than find out at the IVA test

Reply With Quote