Author Topic: Helmet to cage clearances  (Read 6186 times)

0 Members and 1 Guest are viewing this topic.

Offline oj

  • Full Member
  • ***
  • Posts: 61
Helmet to cage clearances
« on: December 04, 2016, 10:23:53 AM »
I can't see where there is a minimum clearance for cage to helmet.  The SFI specs show 4" behind the front hoop and I believe 3" from top of helmet to bottom of cage.  But in reading LSR cars under construction I see much tighter clearances, like a 1/2".
Anybody have experience with what the tech guy will want to see?  I understand there will have to be padding too.
Thanks, Oj

Offline Stainless1

  • Administrator
  • Hero Member
  • ***
  • Posts: 8948
  • Robert W. P. "Stainless" Steele
Re: Helmet to cage clearances
« Reply #1 on: December 04, 2016, 11:05:29 AM »
Are those specs Maximums?
Do you have a rule book yet...
Don't start building without one... especially a Special Construction

1/2 inch from helmet to padding is more than we have... just don't build it so close that your helmet touches.  We had to redo ours a couple of years ago when helmets jumped in external size. If the helmet touches the SFI padding the vibration will uncage your eyeballs.
Stainless
Red Hat 228.039, 2001, 65ci, Bockscar Lakester #1000 with a little N2O

Offline jacksoni

  • Hero Member
  • *****
  • Posts: 1507
Re: Helmet to cage clearances
« Reply #2 on: December 04, 2016, 11:20:06 AM »
I am going to say don't pay attention to SFI specs. Is like people saying NHRA says this and that. SCTA and LSR is different.  Read the rule book carefully. There are minimums/maximums for some clearances well laid out. Side to side is MAX 2" per side but see what Stainless said as well. Too small may be an issue. Over head is 3" minimum. And see what I said in here: http://www.landracing.com/forum/index.php/topic,16439.15.html  reply # 23
Jack Iliff
 G/BGS-250.235 1987
 G/GC- 193.550 2021
  G/FAlt- 193.934 2021 (196.033 best)
 G/GMS-182.144 2019

Offline Stainless1

  • Administrator
  • Hero Member
  • ***
  • Posts: 8948
  • Robert W. P. "Stainless" Steele
Re: Helmet to cage clearances
« Reply #3 on: December 04, 2016, 12:05:02 PM »
Don't make it any tighter than this  :-o  even after our rework helmet sizes continue to grow.  The 3 inch overhead that Jack mentioned is a line running down the front of helmet to a line running down the front of the cage.
Stainless
Red Hat 228.039, 2001, 65ci, Bockscar Lakester #1000 with a little N2O

Offline Glen

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 7024
  • SCTA/BNI timer 1983 to 2004, Retired,. Crew on Tur
Re: Helmet to cage clearances
« Reply #4 on: December 04, 2016, 12:32:22 PM »
Don't forget that the belts stretch and can let your head hit the roll cage.
Glen
Crew on Turbinator II

South West, Utah

Offline jacksoni

  • Hero Member
  • *****
  • Posts: 1507
Re: Helmet to cage clearances
« Reply #5 on: December 04, 2016, 12:57:27 PM »
What Glen said...

 don't have my 2016 book handy, is page 36 in 2015. But relevant paragraphs are 3.B1 and 2 and 3.C. Figure 3 specifically. Also, 3.A.3.
Jack Iliff
 G/BGS-250.235 1987
 G/GC- 193.550 2021
  G/FAlt- 193.934 2021 (196.033 best)
 G/GMS-182.144 2019

Offline SPARKY

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 6908
Re: Helmet to cage clearances
« Reply #6 on: December 04, 2016, 01:41:24 PM »
  My cage is really deep to protect my hands and arms---there is nearly a foot in front of my helmet--makes it harder to get in and out of, but much more protection---

also think about building your seat back to be able to recess the Hybrid Pro HANS device we may have to redo ours to deal with several of the issues mentioned for one of our prospective

 drivers---toward what Sid, SS1 and others have said---  bottom line--it is much easier to build a fast car for a small skinny driver-- than for a large F A ed older owner/driver  :-D   :-o
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure or nothing."   Helen Keller

We are going to explore the racing N words NITROUS & NITRO!

Offline Stainless1

  • Administrator
  • Hero Member
  • ***
  • Posts: 8948
  • Robert W. P. "Stainless" Steele
Re: Helmet to cage clearances
« Reply #7 on: December 04, 2016, 07:59:53 PM »
 
 drivers---toward what Sid, SS1 and others have said---  bottom line--it is much easier to build a fast car for a small skinny driver-- than for a large F A ed older owner/driver  :-D   :-o

Hey wait a minute... Johnboy and I resemble that remark....  :roll:
Of course it is getting harder to get in and out, makes you think the firesuit isn't the only thing shrinking... does steel and aluminum shrink with age  :?
 :cheers:
Stainless
Red Hat 228.039, 2001, 65ci, Bockscar Lakester #1000 with a little N2O

Offline SPARKY

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 6908
Re: Helmet to cage clearances
« Reply #8 on: December 04, 2016, 10:33:48 PM »
That Dodge stuff does shrink---I have documented it---it migrates to my belly---but then on second thought I sure as heck don't have abs of steel
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure or nothing."   Helen Keller

We are going to explore the racing N words NITROUS & NITRO!

Offline floydjer

  • Hero Member
  • *****
  • Posts: 4242
  • "There is no duck side of the moon..."
Re: Helmet to cage clearances
« Reply #9 on: December 05, 2016, 09:19:46 AM »
Fiberglass shrinks too...getting to be a real chore packing myself in my `32 3 window...... :cheers:
I`d never advocate drugs,alcohol,violence or insanity to anyone...But they work for me.

Offline ggl205

  • Sr. Member
  • ****
  • Posts: 956
  • G/FL 218.282 since 1995. G/FL record since 1993.
Re: Helmet to cage clearances
« Reply #10 on: December 05, 2016, 11:15:20 AM »
 
 drivers---toward what Sid, SS1 and others have said---  bottom line--it is much easier to build a fast car for a small skinny driver-- than for a large F A ed older owner/driver  :-D   :-o

Hey wait a minute... Johnboy and I resemble that remark....  :roll:
Of course it is getting harder to get in and out, makes you think the firesuit isn't the only thing shrinking... does steel and aluminum shrink with age  :?
 :cheers:

I have met both you guys and believe I outweigh you both in total (lol). I used to fit in a lay down car. Now I have trouble getting in an F150.

John

Offline Seldom Seen Slim

  • Nancy and me and the pit bike
  • Administrator
  • Hero Member
  • ***
  • Posts: 13158
  • Nancy -- 201.913 mph record on a production ZX15!
    • Nancy and Jon's personal website.
Re: Helmet to cage clearances
« Reply #11 on: December 05, 2016, 11:16:31 AM »
The BED of an F-150?  Geez, that's quite a -- bulk... :roll:
Jon E. Wennerberg
 a/k/a Seldom Seen Slim
 Skandia, Michigan
 (that's way up north)
2 Club member x2
Owner of landracing.com

Offline Stan Back

  • Hero Member
  • *****
  • Posts: 5879
Re: Helmet to cage clearances
« Reply #12 on: December 05, 2016, 11:20:15 AM »
. . . and with those aluminum beds, be careful where you step.
Past (Only) Member of the San Berdoo Roadsters -- "California's Most-Exclusive Roadster Club" -- 19 Years of Bonneville and/or El Mirage Street Roadster Records

Offline ggl205

  • Sr. Member
  • ****
  • Posts: 956
  • G/FL 218.282 since 1995. G/FL record since 1993.
Re: Helmet to cage clearances
« Reply #13 on: December 05, 2016, 12:50:26 PM »
The BED of an F-150?  Geez, that's quite a -- bulk... :roll:
I knew I should be more specific around this group. That would be the front seat of an F150, Jon. Still, quite a bit of bulk, for sure.

John