My car is going to be running low 11's to high 10's. I need to know the minimum point for a roll cage. right now I have 6 point but its not in the car as of yet. I need to know if that is good or do I need an 8 point.

 

NHRA rule.

Roll cage manditory in cars running 10.99 and quicker or any car exceeding 135mph. Full bodied cars with unaltered firewall, floor and body (from firewall rearward, wheeltubs permitted), running between 10.00 and 10.99 rollbar permitted in place of roll cage.

As long as your firewall and floor are stock then the simple 6 point roll bar is good to 10.00. I still need to go through tech inspection to know if my floor modifications for the ladder bars are considered "altered" If it is then I'll need a full cage to run 10's.

An 8 point roll bar such as the one currently on sale from S&W is not a cage. A full cage is a standard 6 point bar plus a roof bar and front a-piller bars. This is also called an 8 point bar. There is usually also a bar joining the a-piller bar with the main hoop along the bottom of the floor as well as the typical door bar.

 

Thanks for the help. So your syin that there is a 6 point cage and a 6 point bar, or something to that effect. I know my car is going to be close to the high 10's, so I need one. A 6 Point roll cage will be fine then. If you know anywhere where i can get a good quality cause I was just going to order an 8 point from summit of jegs, please let me know.

 

There is no such thing as a 6 point cage. Buy a rule book. It explains exactly how each bar is to be positioned for proper setup.

If you only need a roll bar then buy one from anyone who sells roll bars. S&W race cars currently have roll bars for sale. If you feel you need to have a cage then buy a 10 point cage from Chassis Engineering.

 

Also, don't forget if it's a rollbar it has to be 1 3/4" tubing. A rollcage only has to be 1 5/8". Mild steel has to be .118 wall and moly can be .083 wall

 

Call me a moron.. but what exactly is a roll bar?

I didn't know you could substitute those for cages...

Jon

 

A roll bar consists of a main hoop behind the seat plus 2 rear braces and 2 forward braces (door bars). This is a 6 point bar. An 8 point bar also has 2 more bars coming down from the main hoop just below the cross bar and go down toward the SFC points between the main hoop points.

A roll cage has all that plus has a hoop around the roof and across the top of the windshield. There are 2 more bars that go from the front of the hoop down the A-pillers to the mounting point where the door bars attach to the floor. This adds 2 more points to a 6 or 8 point roll bar to make it a 8 or 10 point cage (needs the roof hoop to be called a cage). A 12 point cage has 2 more bars attached to the A-piller bars and go through the firewall to attach to the front part of the frame.

More bars can be added depending on modifications done to the car. A knee bar joins the A-piller bars across the bottom of the dash. A good cage setup will have a sill bar joining the main hoop to the A-piller bars alond the door sills. An extra set of rear bars can be added in an X style for more rear strength.

Not considering convertables, NHRA says you only need a 5 point roll bar (no passenger side door bar) but a 6 point is always the standard installation, as soon as you run quicker than 12.00. The 6 point bar is good to 10.00 as long as the firewall and floor have not been altered. Alteration means cutting out the firewall and moving it back to allow room to set the engine back farther. Cutting up the floor to make an access panel for transmission removal etc are all alterations. Once you've done alterations then the 6 point bar is only good to 11.00 and you need a full cage to run in the 10's. Adding wheel tubs is not considered an alteration. Neither is the sectioning I did for the ladder bar clearance.

 

While were on the subject of NHRA rules. Whats the deal with long wheel studs and a drive shaft loop. My monte has a loop from the factory but its kinda flimsy lookin, will it pass tech? also is there any other little things that they will give me a hassle over?
Thanks for your info

Bronson

 

Wheel studs must pass into the hex portion of the nut no less than the thickness of the stud. If you have 1/2" wheels studs then at least 1/2" of the stud must be in the hex portion of the nut. The hex portion is everything above the surface of the wheel including any washers. Put the wheel on the car and measure how far the stud sticks past the rim including the nut washer if required. If it's higher than the thickness of the stud then you should be ok.

I'm not sure what a Monte's loop looks like. A driveshaft loop must be a minimum of 2" wide and 1/4" thick and must be mounted within 6" of the front u-joint.