Okay, the first gen is at the shop getting a rollbar installed(car is used for autocross, track days, and will see a hillclimb). I heard from a reliable source that an "X" from the hoop back is not NASA legal. Something about only being one complete bar... Anybody have any input on this?

Dan

 

I'm not up to date but NASA were to accept SCCA legal cages also.

 

My brother runs a rear X in his BMW and has been running NASA events for 4 years. The rules do not prohibit an X for the rear bars. There are some rules an maximum and minimum angles. If you are still concerned call NASA or use 2 down bars with a diagonal between the two. The rules are posted at http://www.nasaproracing.com/rules/ccr.pdf For the race cage it is section 15.6

Good luck,
Eric

 

Which bars are you talking about? From the main hoop to the rear shock towers?
I don't suppose your car is at Mitch Piper's shop is it?

If the bars you are talking about are from the main hoop to the rear towers, technically, by CCR and SCCA GCR Specs the cage is illegal. They have had many drag down knock out fights about this on honda-tech in the RR/AX forum (don't knock it, till you try it.), including confirmations from NASA Tech inspectors.

As always, your mileage (and tech inspector) may vary.
Are you building the car for a class or open track? If open track, use both, it won't hurt.

Marcus, who believes if you are discussing some other bars, he just wasted 30 seconds and needs more vodka.

 

I assumed you meant the X inside the parallel straight bars to the rear, is this correct. ie: IXI

 

Did I miss it? I didn't see anything refering to crossing rear bars as illegal. Rule 15.6.11 It seems as long as there are no bends and you meet the 105* and 75* specs you can do what you want. Granted I am not a cage builder and would need to visually see the angles to make sure it would work.

 

If X's are illegal, I will be in big trouble. All of my cages for Road Course have X's in them. I think what you are refering to are the rear support tubes can not have any bends in them like you see in some kits and drag cages.

 

I sent a link to this topic to Jerry@NASA . He said 2 down bars with a diagonal. I sent a response asking "whats wrong with a X?" I have not recieved a reply yet. I'll let you know

 

I think the problem is if there is an "x" without the straight back bars to the area of the rear shock mounts. Making an "X" instead of an "IXI" is an attempt to satisfy the function of the second , without the weight of the straight bars. To make a true "X", you have to run one diagonal, then cut the other diagonal and weld it to either side of the other diagonal. This violates teh letter of the law requiring one continuous tube from hoop to mounting. "IXI" setups are legal for NASA - we just ran one at the 25.

 

Here is the answer on the X

NASA Jerry wrote

 

Sorry- I assumed that was what he meant from his original post, (an x alone) as Jerry mentioned its not legal. East Coast Cage Builder Mitch Piper built lots of cage that way, with an X only.

Marcus

 

Mitch did my cage.... It turns out that NASA has thrown out vehicles for only having the X on the east coast... Luckily, I called Mitch this morning and told him to add straight bars to each side before he finished (IXI)... He works fast... The damned thing is done already!! LOL

Dan

 

The stand alone X rear brace design used to be illegal in the SCCA's IT class. There wasn't a written rule against it, but there was a drawing that noted that the 2 straight hoop braces were required. That note on the drawing misteriously disappeared about 2 or 3 GCR's ago.

With the new IT rules stating that only the required bars needing to meet the min. tubing size, there's no reason not to use the lXl design now, or at least l\l

 

Agreed, and my new cage is |\|
the NASA ruels are due to what Bos noted above.


Marcus