4 replies to this topic

[Brian]

I have an Ultrashield Rally Sport seat on order (two weeks out still). I am having a Miatacage cage being installed now. This is the first time I've gone through this process and am learning as I go.

The welder just called. He asked how high the seat belt holes are on the seat so he can weld the rear cross bar properly to keep the belt angle in the proper range as per the SCCA rules (there is mention of this in the manual that came with the cage).

My questions are this, what is the proper belt angle range (I couldn't find a mention to an actual angle in the SCCA book) and does anyone know how high up the holes in the seat are? We will be mounting it straight to the floor.

Thank you,

Brian

[Tom Hampton]

Strictly speaking the guidelines are dependant on your harness and HNR manufacturer. However, Shroth Racing has an excellent guide to give you the basics of installation:

http://www.schrothra...nstructions.pdf

or the HTML version:

http://www.schroth.c...s/en/index.html

In general, Shroth has an excellent and informative site.

Ultrashield also has some information:

http://www.ultrashie...system-info.pdf

If you call UltraShield they will tell you the exact dimemsions of the holes you are interested in. I drove down to their shop to my my seats. Great group of guys!

You can get a rough idea from these:

http://www.racedaysa...m/vshamech.html


More imporant is where your shoulders will be (rather than the seat holes themselves). There is a big spread between the top and bottom of the holes in the seat. I mounted my harness bar so that the belts are exactly level coming off my shoulders WITHOUT an HNR. The HNR will add a small amount of height to my shoulders so the belts will be 2*-5* down (within the 0-20 degree down recommended.).

[davew]

I recomend waiting on the seat befor building your cage. Not only seat position, but the length of your torso will effect the crossbar position

Dave

[dmathias]

SCCA GCR
9.3.19
C. The shoulder harness shall be the over the shoulder type. There shall be a single release common to the seat belt and shoulder harness. When mounting belts and harnesses it is recommended that they be kept as short as reasonably possible to minimize stretch when loaded in an accident.

The shoulder harness shall be mounted behind the driver and supported above a line drawn downward from the shoulder point at an angle of 20 degrees with the horizontal. The seat itself, or anything added only to the seat shall not be considered a suitable guide. Guides must be a part of the roll cage or a part of the car
structure.

Only separate shoulder straps are permitted. (“Y” type shoulder straps are not allowed.) “H” type configuration is allowed.

[Gunpilot]

I also used a Miatacage. I went with the installation option where the rear brace sat just on top of stock seatbelt tower (minimized additional cutting). See picture below. I currently use an off brand race seat that looks very similar to the Ultrashield Rally Sport and it works fine (meets regulations). I have recently ordered an Ultrashield and hope it fits the same. My seat is currently mounted directly to the floor with a 20 degree layback.

I do recommend having the seat available for placement purposes, just as the hardtop should be available for best cage fitment.