Senior Stig
Senior Stig New Reader
2/18/20 1:59 p.m.

Hi!

First post from noob. Just got my novice permit from SFR SCCA school last weekend.

I need to send my car to the fab shop to be caged for SCCA T2 and NASA ST2. Am cross-eyed from reading the rule books. For my car (C5 Z06, fixed roof, ~3200lb:~400hp):

 - SCCA GCR (page GCR - 95 at https://www.scca.com/downloads/48599-gcr-february-2020) says: "Over 2699 lbs: 1.50 x .120, or 1.75 x 0.095, or 2.00 x 0.080"

 - NASA CCR (page .. at https://www.nasaproracing.com/rules/ccr.pdf) says: "3001 - 4000lbs: 1.75" x .120"

Does that mean 1.75" x .120" will allow my ~3200lb C5Z to run in both? Would love to hear from the experienced folks here.

Thanks in advance.

Tom Suddard
Tom Suddard GRM+ Memberand Director of Marketing & Digital Assets
2/18/20 2:02 p.m.

Yes, that's correct, at least the way I read it. That's what we used in project 350Z. 

https://grassrootsmotorsports.com/project-cars/LS-Swapped-2003-Nissan-350z/project-lsz-building-cage/

malibuguy
malibuguy GRM+ Memberand Reader
4/27/20 7:07 p.m.

im glad I saw this.  going to  be doing a cage on a friends car that sees a little of everything.  little heavier then the vette

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
4/27/20 7:17 p.m.

Put in a few extra bars and you can make it legal for stage rally as well ;)

Tom1200
Tom1200 Dork
4/27/20 8:33 p.m.

We back in 1989 when we put a cage in the Datsun we used an Autopower 1.75 .120 wall kit  and then upgraded it to a rally spec cage. Major differences being the gussets in the corners of the halo, the addition of sill bars (door bar down at the sill) and larger foot print where the flat plates meet the floor.

The rally cage will be heavier but it will take a mighty wallop. I could have used 1.5 tube in the car but chose to go with overkill. I figured the extra 30-40lbs is worth it.

drock25too
drock25too New Reader
4/27/20 9:01 p.m.

I suggest You take the rules  with the car and let them make suggestions.  I have a friend who builds dirt track cars and he put the cage in my car and that is the first thing he asked for.  He studied the rules before he ever picked up a tube. 

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
4/27/20 9:48 p.m.
Tom1200 said:

We back in 1989 when we put a cage in the Datsun we used an Autopower 1.75 .120 wall kit  and then upgraded it to a rally spec cage. Major differences being the gussets in the corners of the halo, the addition of sill bars (door bar down at the sill) and larger foot print where the flat plates meet the floor.

The rally cage will be heavier but it will take a mighty wallop. I could have used 1.5 tube in the car but chose to go with overkill. I figured the extra 30-40lbs is worth it.

Rally cages now actually have additional bars - most notably a second bar running from the top of the A-pillar in a straight line down to the foot of the front hoops (and intersecting with the door bars) for vertical support on rollovers and roof hits (not a big issue for track cars lol). I think compared to '89 there is at least one additional backstay bar and one additional main hoop bar (has to be a full cross now, with four central gussets). And most of the good cages use plinth boxes rather than flat plates on the bottom these days, FIA-style. Rally cages from the 80s can't even be grandfathered in at this point without significant modifications, to my knowledge. 

I was being somewhat faceitious about him adding a couple bars to make it a rally cage (unless he plans to rally)...most of the additional rally bars are for hits directions that are pretty unusual in road racing. 

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
4/28/20 1:37 p.m.
drock25too said:

I suggest You take the rules  with the car and let them make suggestions.  I have a friend who builds dirt track cars and he put the cage in my car and that is the first thing he asked for.  He studied the rules before he ever picked up a tube. 

I agree, you want a cage builder who is not just an expert at welding but also at cage design and fitting the stiffest, strongest, safest, and lightest cage that fits within the rules.

Your profile says you're in Palo Alto, CA?  If so, I recommend talking to Tony at TC Design in Campbell, he's generally regarded as one of the best cage builders on the west coast for this kind of thing.

 

malibuguy
malibuguy GRM+ Memberand Reader
6/5/20 5:32 p.m.

is there a bend radius rule...?

so apparently my shop landlord has a JD2 model 32 tucked away somewhere with a hydro mod.  he says Im welcome to use it anytime just buy the tooling I need.

for 1.5" JD2 has 5.5 and 6.5...i plan to buy 1.5" tooling first, eventually 1" and 1.75" after i make my first million

lotusseven7 (Forum Supporter)
lotusseven7 (Forum Supporter) Reader
6/5/20 5:47 p.m.

The normal wording for most rulebooks is that the bend radius needs to be at least 3x's the tubing OD. Never had an issue with SCCA, NASA, FIA or any of the Marques groups. Lots of groups default to the SCCA GCR.
 

I have a for round tubing, a 1" x 3" radius, 1.5" x 4.5" radius  and 1.75" x 5.5" radius dies.

malibuguy
malibuguy GRM+ Memberand Reader
6/5/20 5:59 p.m.
lotusseven7 (Forum Supporter) said:

The normal wording for most rulebooks is that the bend radius needs to be at least 3x's the tubing OD. Never had an issue with SCCA, NASA, FIA or any of the Marques groups. Lots of groups default to the SCCA GCR.
 

I have a for round tubing, a 1" x 3" radius, 1.5" x 4.5" radius  and 1.75" x 5.5" radius dies.

Exactly the guide line I needed.  Thank you so much.

lotusseven7 (Forum Supporter)
lotusseven7 (Forum Supporter) Reader
6/5/20 6:24 p.m.

Before you do anything, check with the sanctioning body that you are going to run with and the class that you  are building the car for. Check the rules for car weight, tubing size, attachment plate thickness, number of attachment points and general cage design. Some groups are tricky with their rules. Get a rule book and read it cover to cover. Then, read it a few more times.

 

Good luck.

BarryNorman
BarryNorman New Reader
6/6/20 2:24 a.m.

In reply to codrus (Forum Supporter) :

Also, Blaine Fab. in Santa Cruz, I think. Proprietor is a nasa tech inspector also.

ddavidv
ddavidv PowerDork
6/6/20 5:49 a.m.

Corvettes are odd animals to put bars/cages in because of their construction. I'd consult with a few guys who have Corvettes who have done it to see what suggestions they may have. Just bolting one to a floor made of fiberglass and plywood isn't the best plan for safety.

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