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Slide the seat forward and slouch a little. Do a foamectomy. Remove the seat, oval out the forward mounting holes in the rail, and bend them up a little to get the front of the seat lower.

That is an option, i've seen cages with a horizontal support that goes around the back of the seat but it is never in the main hoop. I wonder if these rules from NASA can be worked around because I want to do an HPDE at road atlanta once in a while.

So based on these rules I could get away with a half halo only if I went up one weight class and used 2" tubing which is rediculous and not going to happen.

I need to buy a drill and make brackets for my damn seat so I can see how low i'm sitting in it when bolted to the floor. Guess i'll go rip out the stock seat now real quick and drop it in there on the sliders and see what that gets me.

Quote:

15.6.6 Main Hoop
The main roll cage hoop should be as wide as the full width of the interior and must be
as close to the roof as possible without violating CCR section #15.6.20 Inspection. One
continuous length of roll bar tubing shall be used as the main hoop. The main hoop
must consist of not more than four (4) bends maximum, totaling one hundred eighty
(180) degrees +/- ten (10) degrees.

Quote:

15.6.19 Bending Allowances
If the maximum number of bends permitted for any one bar is exceeded, all required
components shall be made from the tubing size listed for the next heavier category and
must be approved by a NASA race tech shop or scrutineer.

Quote:

11.4.7 Roll Bars
All open cars should have a roll bar installed to help protect the occupant(s) from injury
during a roll-over. The roll bar should be able to withstand the compressional forces
involved in supporting the full weight of the car. The roll bar’s main hoop should extend
the full width of the car (except certain cars that have been approved by NASA). The
main hoop shall be one continuous piece with smooth bends and no evidence of
crimping or wall failure shall be present (i.e. should be Mandrel bends). All welds should
be of the highest possible quality, with full penetration [Ref:(15.6.15)]. All cars with roll
bars are required to have adequate roll bar padding per CCR section #15.6.4. In cases
where the driver’s head may come in contact with the roll bar should the seatback fail, a
seatback brace is required in conformance with section #15.6.22. The material and
minimums are as follows: (All cars with full roll cages should conform to the applicable
sections found in section #15.0.)

Vehicle weight DOM or ERW
Under 2000 lbs. 1.50" x .120”
2001 - 3500 lbs. 1.75" x .120"
Over 3500 lbs. 2.00" x .120"

Vehicle weight Alloy (CM)
Under 1500 lbs. 1.375" x .095”
1501 - 2500 lbs. 1.625" x .095"
Over 2500 lbs. 2.000" x .095"

Also the stock standoffs for the stock seat, are they actually part of the floor pan, or are they just spotwelded in place? I was thinking of going to a fixed back seat to allow me to get low enough, and sidemount the seat and bolt the brackets to the floor pan.

They're part of the floor via spot welding.
http://targamiata.com/images_lrg/IMG_6621.jpg

chad, all you gotta do is get the car under 2001 lbs and you can use the 1.75 hard core tubing diameter.... :)

good to know the rules though. it'd almost be worth a 2" bar just for the main hoop if it got it off my head.

Sweet, I guess I know how I will be mounting the seat I get.

All of this indecision is killing me softly.

bliss is buying the hard core bar before thinking too much about it.

Quote:

Originally Posted by y8s (Post 226512)

bliss is buying the hard core bar before thinking too much about it.

I hear that. i think we bought our roll bar about 6 years ago. just wanted something that fit under the hardtop and had a harness bar...didn't think much about anything else.

Quote:

Originally Posted by y8s (Post 226151)

here I drew a picture:

Now that's Cal Poly engineering design for you. ;)

So I have come to a conclusion.... ok not really. The seat is still on the sparco sliders and it's just sitting in there in the general position it will be in when i'm done with it.
Attachment 214162 Attachment 214163 Attachment 214164 Attachment 214165

Then judging by these photos, both of which are using the standard HDHCDD, i think I will be just fine with the seat bolted to the floor or on sliders even.
http://memimage.cardomain.net/member...55_12_full.jpg
http://memimage.cardomain.net/member...55_11_full.jpg
http://memimage.cardomain.net/member...55_13_full.jpg

Ordered the M2 HDHCDD HT bar. I decided that because no matter what I do the bar will be close to my head so I might as well be able to pad it. So with the hardtop bar, I won't have any issues using the HT both with the sidelatches(not really an issue to begin with) or with the bar making contact with the HT itself. Plus, with the extra clearance I can pad the HT model bar to help keep my noggin safe.

But once I have the momo I deem the bar completely unsafe, I will sell the HT bar. Make a different bar that is taller as well as try a different seat. Such as a kirkey bolted to the floor. Those are all options but I wanted to take advantage of the free shipping now because I don't see used bars coming up for sale often enough.

chad, you know you can always sell a HD bar for almost what you pay for it...so you made a good choice...
Im thinking about an Ultrashield or Kirkey myself eventually...

Got my hardcore today, install tomorrow, pictures to follow.

2" helmet rule abider? I'll never make it, WHO CARES

Well i've had the bar installed for a few days now and i'm super happy with it. It has tightened up the car a good bit and I'm loving that part. I'm also really happy i ordered the standard hardcore instead of the HT version. With the seat back and fully reclined my head goes just under the bar in normal driving position. If I tip the seat up a little to where I actually driver the car then I still don't come close to hitting the bar.

Went to my first autocross today and had a blast. Here are a couple pictures the g/f took of me in the car while in grid. With the helmet on my helmet hits the seat and doesn't come close to hitting the bar. Couldn't be happier.
The person in the green hoodies is kyra, not I. So keep the height difference in mind. She just wanted some poser shots to show friends. She did ride along the 2nd run so that was fun. She wouldn't ride along again after that though.
Attachment 213740
Attachment 213741
Attachment 213742

Looks great chadwick, glad to hear your choice worked out.

I was going to ask what the hell class "NSMZ" was but then figured out it was SM2 novice..

sweet chad, glad you are happy with the non- hard top bar.

vettes and 3rd gens and s2ks oh my. those pics really make me want to try an auto-x this year.

glad it worked out

Quote:

Originally Posted by Ben (Post 235983)

vettes and 3rd gens and s2ks oh my. those pics really make me want to try an auto-x this year.

glad it worked out

That's not even the best ones. There was a C6R, another amazing Z06, STI, real RHD silvia, a mean RX8 that sounded like it was going to eat you, a camaro that made the corvettes sounds like hondas, and of course a bunch of other awesome cars. It was awesome to be able to race and push the car as well as being able to be around all kinds of car enthusiasts that care about real car modification instead of LED washer nozzles.