I know a few here own LSR projects or finished cars. If any of you get a chance could you measure from the top of your cage to the top of your head when you're in it and suited up? Ever seen an A coupe with a Gurney bubble?
Kevin, no one on our team has more than an 1" clearance. I'm the tallest at 6'3", and have to scrunch down to get any clearance!
Thanks but... Not looking for clearance between helmet and cage literally want the (ballpark) measurement from top of head to top of cage when seated. As in, will I need to add a blister to fit a cage when looking out of the windshield.
Wasnt Ryan going to put Guerny bubbles in his coupe at one point when it was going to get a mega chop and still fit is long lean frame inside of it? I got nuthin to measure for ya kid, I wish I did.
Man... maybe I need to go about this by asking a different question. How much vertical distance is there between your eyeballs and the TOP of your roll cage when seated in your car? Or maybe, How thick is the typical Snell approved helmet? (I might be able to rough it in from there) I'm dealing with a heavy chop and low roof crown Just trying to figure out if I'll need to add a bubble to the roof or cut eyeholes in my firewall.
Kevin, 3.5". That's with 1-5/8 tubing, 1" of padding, and very little helmet to pad clearance. Hope this helps!
It helps, so I'm still trying to find the thickness of a typical Snell helmet to get me in the ballpark then. Thanks.
There is a Studebaker (ex-Burklands) with the roll bar sort of molded into the roof. In my '32 which was not chopped but was channeled the width of the frame I had head room. Don't have a real inches measurement for you. I guess you will have to sit in the car and measure your exact clearances. I'll put my Bell helmet at 2 inches thick, but that is a rough measurement and I don't want to cut it in half for a good one.
Kevin this would be more helpful posted on the landracing.com site. There are some really good photographers on there and more racers that have had to face the same issues. Just like the HAMB but land speed racing oriented. Tons of helpful people that have passed tech and set records. Really never met someone at Bonneville that wouldn't help in any way possible. Great folks and many SCTA officials and tech guys answer questions in the forums.
I agree with Richj- about 2". So that makes it 5.5" for a VERY tight fit, minimum. Kevin, what kind of car/class are you building for?
Is there such a thing as a typical snell helmet? I went to Speedway expecting to be fit for a helmet from the catalog at $189.00 The second one off the shelf fit good. The hole in front wasn't big enough for my glasses to fit through. The Bell I walked away with was $389.00 Expect to stumble when heading to the salt.
Remeber the "HANS" Device you wear. I leave my HANS buckled up when exitting my Belly Tanker, however; I put quick release system on the sides of the helmet which releases the tether strap, allowing the HANS Device to fall backwards. Quite often the top of the HANS hits the front hoop when you are exitting your car. This obviously depends on your roll cage style, etc....
I believe the answer to your question is that however you do it, the head has to remain inside the plane of the roll cage at all times. I don't think a bubble like the one on that GT would pass tech at Bonneville. If that guy's head is up in that bubble, or it can get up into that bubble, it is outside the plane of the roll cage. I'd make a drawing of what I wanted to do and email it to the chief car inspector before I spent any more time at all thinking about it. Contact information is here: http://scta-bni.org/contact.html
Kev, there are some shots in my thread. post 196, 217. Plus Tim has shots in there of his SA 2010 Helmet with a tape measure for reference. The old red Bandit pictured was the same size as a new legal helmet. http://www.jalopyjournal.com/forum/showthread.php?t=545509&highlight=spirit&showall=1
None of us here can give you a definitive answer. Best thing is to email Lee Kennedy. [email protected]
Reverborama pretty well nailed it when he said that SCTA wouldn't allow anything like that Gurney bubble, That was early 60's technology and I doubt any sanctioning body would allow it now. Remember that you still have to be able demonstrate that you can exit the car on your own in X amount of time or less too.
I would think your best bet is to get the helmet your gonna use, then you know for sure, i would wonder if all schnell approved helmets are the same thickness above your head, i have a snowmobile helmet that i bought 2 years ago thats schnell approved and could measure that if it helps get a average measurement. JEFF
I think you guys are missing what Kevin is saying, hes gonna put the rollcage "thru" the roof and put a gurney bubble to cover it
might as well buy the helmet before you build the cage ?? channel the seat . SINK IN TO THE CAR. RATHER THAN BUILD UP.
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