seat mounting

[dickita15]

Is was brought up in the cage stiffness thread that some very well installed seat mounts could violate the 8 point cage attachment rule. The setups I like the most attach to the cage on the left and rear but on the right all you have to attach to is the tunnel. I think a well mounted seat is worth looking at an exception to the 8 point rule. how could this be written so as not to let the cat out of the bag on cage attachments while still giving you a solid seat mount

[turboICE]

There is no way around it unless you are using an FIA seat and you have to have a seat back mount to the main hoop or cross brace. If in order to firmly mount it you had to attach a seat mount to some part of the chasis then you would have to have a chasis connecting point from the rear support thorough the seat to the chasis. But most seats make poor stiffening components though.

I can not conceive of any design that would absolutely necessitate a direct connection from the cage to the chasis to firmly mount the seat. There is nothing I can think of that necessitates a tube attached from the door cross brace or a main hoop cross brace to the tunnel. A mount from the door cross brace to the seat and a mount from the tunnel to the seat sure - but an additional direct cage mounting point, I wouldn't think so.

My base mount from a lower main hoop cross brace and the lower door bar cross brace mounts the seat plenty firmly without attaching to the tunnel and I am not a light person.

In no way would I want a seat that is attached to the cage in one place and the chasis in another - all cage or all chasis. (I prefer all cage since I have more confidence in it.) I don't want the seat yanked apart or twisted if the cage and the chasis decide to go their seperate ways.

[ddewhurst]

Interesting question of ruel 18.4.5.

The drivers seat SHALL be firmly mounted to the STRUCTURE of the car.

What is the STRUCTURE of the car ?

[dickita15]

ed
one car we have has a kirky style seat supported on the sides by plates. the plates are attached to 1" tubing that goes to the drivers side door bar, the tunnel and at the rear to the cage at two points. well supported but I think notto the letter of the rules. at Lime Rock I saw a new IT car this year where the seat was attached to a 1" square tubing frame. That frame was attached to the floor the cage on the drivers side, the rocker on the drivers side, the main hoop of the cage and I think the tunnel on the right. It was a great installation but I am not sure it would stand a protest.

david
good point what is structure. in once sense it may be better for the rule book to be vauge in order to protect the club.

[turboICE]

Oh I can think of an infinite number of ways that the seat could be firmly mounted that would create one or more additional cage points - what I was saying is that I can't think of a set up that HAD to use one of those ways rather than a firm mounting that wouldn't constitute an additional cage point.

[Speed Raycer]

{talking out of my rear} Technically, only cars running an FIA seat w/o a back brace meet the cage point rules. A non FIA seat is an attachment point when running the required back brace. So, until someone protests someones seat as an attachment point, we wont know for sure. If the seat attachment is found legal, THEN we've got to move on to define "the structure of the car"

Basically, where's the line between mounting the seat with Grade 8 bolts and a seat back brace and mounting with a tube structure that's welded to the cage and has one brace that's welded to the tranny tunnel?

{rear talking off}

[turboICE]

I think in general calling a seat a mounting point would be a stretch though a seat mount could definitely become a mounting point done certain ways.

In that case all cars are illegal because the anti-submarine belt must be attached to the floor structure so through the connection through the release with the shoulder harnesses attached to the cage becomes a mounting point...

While defining the structure of the car they whould then define "mounting point" as well. For instance if the plate connecting a seat mount bar to the tunnel was less than 2" wide or less than .080" thick, it wouldn't qualify as a mounting plate so could it really be a mounting point?

[Grumpa]

I mounted my seat to the cage, my logic being that if I get nailed in the driver's side I would rather move with the cage as opposed to the cage moving into me. Since I race a front driver, I was able to weld a crosstube into the front downleg/mainhoop lower tie tubes and mounted the seat to the crosstube and the lap and subbelts to the cage. Which to my peabrain, made a lot more sense than mounting the belts and/or seat to the floorpan. I personally feel that the cage/harness/seat should be one assembly instead of two. Geoff Bodine's crash in the truck race at Daytona a few years back graphically illustrates the logic that I refer to. I know that we don't approach those velocities, but I would rather be safe than sorry. I am a little surprised that the GCR doesn't spell out seat and belt mounting points more clearly.