5/19/16 8:01 PM USAC SPRINT TECHNICAL UPDATE: CAR CONSTRUCTION

http://usacracing.com/news/sprint-ca...r-construction







USAC TECHNICAL UPDATE – TB2016-SP002

SPRINT CAR SERIES

Date: May 19, 2016

Date Effective: May 19, 2016

TITLE: Car Construction

304 Roll Cage and Chassis

A. All cars must have a roll cage, which is integral with the frame anddoes not encroach upon an imaginary cylinder, 20 inches in diameter, extending through the top cockpit opening directly above the seat. The roll cage should extend four (4) inches above the driver’s helmet when seated in the driving position.

B. The following are the minimum frame/chassis material requirements.************************************* ********************************************

**** Must be constructed of 4130 normalized tubing

**** TOP RAILS 1 1/2” x .095”

**** BOTTOM RAILS 1 3/8 x .083”**

**** ROLL CAGE UPRIGHTS 1 3/8” x .083”

**** ROLL CAGE CROSSMEMBER 1 1/2” x .095”

**** UPPER RAILS 1 3/8” X .083”

**** REAR END SAFETY BAR HIGHLY SUGGESTED 1” x .083”

**** Maximum width of main frame tubes 29 1/2 inches

So does it put someone out there now out of a ride or is it just precaution?

I'm having a brain fart here about this, does this mean USAC wants bars across the top of the cage now? If so I was in favor of this till a friend showed me some photos of cages that collapsed due to these bars. It was more than 1 car that had the cage collapse in a crash. Maybe if the bars went from corner to corner so the uprights can support the weight in case of a crash. The 4" from top of cage to drivers head I like, told a driver that at a race & he went out got on his head & got hurt. Those belts stretch drivers, don't fool yourself they don't, you see a car that's been in a real serious violent wreck go look at the stitching on the belts. They're probably not in a straight line anymore, toss those belts out. Be safe out there, many of you I call friends out there, God Bless

I just took it to mean the front and rear ends of the roll cage, maybe some clarification is in order, just sayin!😂Bob

I generally agree this is probably a good thing, however-effective yesterday? That should probably say next year. Even a tall cage car doesn't give most drivers 4" of head room. They will kill their car count the rest of the year and keep any locals from running with them for awhile.

I actually read it completely opposite. I think that it bans all of the over head bars.

does not encroach upon an imaginary cylinder, 20 inches in diameter, extending through the top cockpit opening directly above the seat.

Most of the halo bars are directly over the driver. It would be nice for some clarification.

Usac used to strickley enforce the 4 in rule when Norm was in charge dont think they care much anymore just want car count seen some things at race tracks now old Norm would say just load it back up lol

I wonder if this has anything to do with Stockon not being allowed to run the Woo show at Haubstaubt because his cars tubing did not meet Woo standards. Wonder if that opened USAC's eyes that guys might be building their cars out of thinner tubing. Just a thought.

No one is out of a ride.
It is the existing rule, except for the thickness of the lower frame rails.
The issue was brought up after the WoO race at Tri-State.
The rule was changed to allow a huge portion of the existing cars to be legal.
Our car was already legal, but I commend USAC for making a common sense, quick decision to put the issue to rest.
Gas City tonight, full field, best Non Wing racers on Earth minus a few.

Im not sure what that was about. WoO also changed the rule on the wing mount tubing as some of them had been collapsing, Could have had a old one.

I doubt he was trying to get away with anything, Home track.
We'll probably never know and the real reason is known only by WoO and Stockons team, As it should be.

That four inch rule certainly wasn't in effect back in the days Sheldon Kinser's head stuck out three inches above the cage.