Seat mounts

keycom

keycom

New member
Searched the archives, but couldn't find an answer other than the seat SHOULD be mounted to the cage.

Beginning cage construction next week and want to mount the seat to the cage, not the floor.

Anyone got any pics of how they did it? Trying to avoid the 9th, 10, and 11th cage mounting points.

And pics of window net mountings too would be helpful.

Thanks all!
 
I can't think of any legal way you can do that. - GA
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GCR 9.4.2.D.1 ...Any number of additional reinforcing bars are permitted within the structure of the cage...

Put horizontal bars as low as possible 1) from the base of the main hoop on the driver's side to the base of the front down tube 2) between the bases of the main hoop (across the car) 3) from the base of the main hoop on the right side to the base of the front right down tube and 4) across the car from 1) to 3). Place 4) so that the front of the seat mount can be secured to it. 5) Depending on the configuration of the floor, attach another tube from 2) to 4). The two longatudinal tubes - 1) and 5) plus the lateral 4) - give you three sides to attach the seat bracket to. If the seat attachment tubes are too high, fab a bracket that welds to the top of the tube and drops down to the bottom of the seat bracket.

Since the additional tubes do not touch the floor or frame, there are no additional attachment points. And the seat attaches only to the cage.

Now, I am making no claims about the additional weight. If your car is at minimum weight, this should not be an issue. If I were to add weight by adding cage tubes, I could lose about 40 lbs with lighter wheels.

Hope this helps.
 
Take a good look at the OEM attachment points and expand from there. Add additional padding like is done on roll cage mounts to spread the load if necessary.

At least that's what I plan to do. I cound not come up with a way to tie it to the cage w/o adding additional attachment points or a ton of weight.
 
Where did you come up with the requirement for the seat to be mounted to the roll cage. IT cars are to be built to the Showroom Stock cage rules 9.3.2 section J. "The drivers seat shall be firmly mounted to the structure of the car. In cars where the seat is upright, the back of the seat shall be firmly attached to the main roll hoop, or it's cross bracing."

Chuck
 
"Searched the archives (of the IT Forums), but couldn't find an answer other than the seat SHOULD be mounted to the cage."

As you can see, I didn't say I found that it was required.

Rather, for safety reasons, the seat SHOULD be mounted to the cage and move with it during an accident, rather the seat bottom moving with the floorboard and the seat back staying with the cage.

"My opinion" has been influenced by those who say the seat should be mounted either to the floor or to the cage, but not both. I don't have an FIA seat, so I choose to mount the seat entirely to the cage.

"The drivers seat shall be firmly mounted to the structure of the car." No one has apparently defined STRUCTURE.

This is not the place to discuss THAT issue, there are other posts on this site relating to THAT.

Rather, I was just seeking pictures of cage mounted seats and pictures of window net mountings.

PLEASE take my opinions with a grain of salt as this will be my first year of competitive racing. :D

Thanks!
 
I just modified my stock seat rails by welding 1/4" plate to the top of the rails against the rails themself and the structure of the car and bolted to that.
 
Every tech inspector I've spoken with wants to see the seat attached to the car structure not the cage. Personally I have not seen any examples of professional teams mounting to the cage.
 
I don't have an FIA seat, so I choose to mount the seat entirely to the cage.[/b]
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Oooo! Oooo! Oooo! You guys are gonna hate me.

ITCS states:

- "The driver’s seat (only) shall be replaced with a one-piece bucket-type race seat." Minimal limitations to its design. So, you can actually fab your own (witness some of those older Kirkey seats)
- GCR (SS cage rules) states: "The driver’s seat shall be firmly mounted to the structure of the car."
- GCR (SS cage rules) further states: "In cars where the seat is upright, the back of the seat shall be firmly attached to the main roll hoop, or it’s [sic] cross bracing." No limitations to this bracing.

You see where I'm going, right? C'mon, don't make me say it...
 
Oooo! Oooo! Oooo! You guys are gonna hate me.

ITCS states:

- "The driver's seat (only) shall be replaced with a one-piece bucket-type race seat." Minimal limitations to its design. So, you can actually fab your own (witness some of those older Kirkey seats)
- GCR (SS cage rules) states: "The driver's seat shall be firmly mounted to the structure of the car."
- GCR (SS cage rules) further states: "In cars where the seat is upright, the back of the seat shall be firmly attached to the main roll hoop, or it's [sic] cross bracing." No limitations to this bracing.

You see where I'm going, right? C'mon, don't make me say it... [/b]
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Yes, I know exactly where you're going... a chassis-stiffening seat structure.

But there is another way to peel this onion that will make your eyes water even more. IMHJ, the way the rules are written (or more importantly the way they are cross referenced), it may not even be permissible to use the SS cage ruleset to determine how to mount your IT seat, and it is definitely not required!

Let's look at the paragraph in the ITCS that points you at the SSCS cage requirements:

10. Safety
a. All cars shall have a roll cage installed. The cage shall meet GCR Section 9.4.2., requirements for Showroom Stock cage configuration, tubing size, and material, except as provided for in these rules.[/b]
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Well, guess what? First, it doesn't say squat about the driver's seat - only cage config, tubing, and material are mentioned. And further, the driver's seat requirements are provided for in these (ITCS) rules... it's the paragraph that Greg quoted above, shown here in it's entirety:

a. The driver's seat (only) shall be replaced with a one-piece bucket-type race seat. Factory seat tracks/brackets may be modified, reinforced, and/or removed to facilitate replacement mountings provided they perform no other function. All other seats may be removed.[/b]
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This paragraph provides all the rules you need to mount your IT driver's seat. Therefore, the SSCS seat requirements are null and void. And incidentally, in any case, the underlined part of the ITCS seat paragraph would seem to nullify any attempt to stiffen the chassis by building a 900 pound gorilla seat.
 
Somebody give Gary a cookie.

I agree with your logic, Gary. However, I counter that the various "prohibited function" clauses were neutered long ago, are totally unenforceable, and can never be upheld in a protest/appeal situation. - GA
 
Please, no cookies! I've already put on enough weight this winter. :(

WRT "prohibited function" clauses, I tend to agree they may be unenforceable, at least in many cases.
 
Wow, :014: and all I wanted was some pics of seat mountings and window net mounts. :D

I'm coming up with some new ideas now!
 
So did you get what you were looking for in the end? I have not seen an IT seat mounted to the cage, but I have seen it in GT and SPO cars. My cage and seat mount were done by a very experienced shop and the seat is mounted to the stock locations on the floor (solid frame, no sliders) and one seat back brace to the coss tube. I have a first gen RX-7 and the cage and Unibody work together as the structure....it is by no stretch a tube frame car where the cage is the structure. My inexpert opinion is that if the cage and unibody move significantly in different directions from each other I don't think the seat mounting points are going to be very relevant anymore.......I believe I'll be screwed no mattter where the seat is bolted if that occurs.
 
Good point. With a well designed cage, if the floor moves a lot relative to the cage, you have all kinds of problems to deal with - regardless of how the seat is mounted.

IMO the performs no other function clause does not prevent mounting the seat to the cage. I have seen cars with the driver side of the seat mounted to the cage, on that side only, and the passenger side mounted to the tunnel structure of the car - with no structure between those mounts. Those mounts on the cage serve no other purpose than to support the seat. The fiberglass seat is an order of magnatude less stiff than the steel tube that some would like to argue it is 'stiffening'. If the tube saw enough load to deflect far enough for the seat to provide any significant reinforcement, then the race, and possibly the car is pretty much done. The rule doesn't say 'can not potentially perform another function', some will enjoy arguing the point, but if it is not stiff enough to actually provide added chassis rigidity, then it does not perform that function. I can deflect the seat with my wimpy 6'4" 175lb ectomorphic guns, but have not been able to bend steel bars for a while now. :P

I do see how someone could create a 'stiffening' seat mount, by installing a steel mounting structure bridging between the cage and the tunnel. I just have not seen it done in practice myself...yet.

Man seat mounts and glove boxes, winter interweb racing is getting boring. Makes me look all the more forward to spring racing! :eclipsee_steering:
 
If the seat back brace bothers you, get a FIA 8855-1999 certified seat. These seats are exempt from the seat back brace rule per GCR 9.4.1.B .

The rules governing driver side window nets are GCR 9.3.52 . It is hard to give suggestions without seeing how the door and roll cage meet each other. I just used an off the shelf kit, but will change it when I add the NASCAR style door bars in a few weeks.
 
***Man seat mounts and glove boxes, winter interweb racing is getting boring.***

MAN, am I glad you didn't add the words storage box & or bin to your statement. :D
 
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