[carnahan]

i bought a 95 s-10 with a 10 point cage. the bars that go to the rear of the truck do not come off the top hoop. they come off the crossbar just below the top hoop, kinda behind the back of the seat. does anybody know if the cage will certify NHRA that way or do they have to come off the top hoop. thanx for the help.

[Overdriv]

This is from the 2010 rules book. I would say no, it won't pass. How fast are you going to be going?

Full-Bodied Cars
On full-bodied cars with driver in driving position, helmet must be in
front of main hoop. If helmet is behind or under main hoop,
additional tubing same size and thickness as roll cage must be
added to protect driver. Main hoop may be laid back or forward, but
driver must be encapsulated within the required roll-cage
components. On unibody cars with stock floor and firewall (wheel
tubs permitted), the roll cage may be bolted or welded to the
floor/rocker box via 6-inch x 6-inch x .125-inch steel plates similar to
the roll-bar attachment requirements of paragraph 4:10 in this
section. Unless attaching to OEM floor or frame, the minimum
requirements for a frame member to which a roll-cage member is
attached are 1 5/8-inch x .118-inch MS or .083-inch CM round
and/or 2-inch x 2-inch x .058 MS or CM rectangular.



Section 20 - General Regulations 20.25
All cage structures must have in their construction a cross bar for
seat bracing and as the shoulder harness attachment point; cross
bar must be installed no more than 4 inches below, and not above,
the driver’s shoulders, or to side bar. All required rear braces must
be installed at a minimum angle of 30 degrees from vertical and
must be welded in. Side bar must pass the driver at a point midway
between the shoulder and elbow.
Unless an OEM framerail is located below and outside of driver’s
legs (i.e., ’55 Chevy, ’65 Corvette, etc.) a rocker or sill bar, minimum
1 5/8-inch x .083 CM or .118 MS or 2-inch x 2-inch x .058-inch CM
or MS rectangular, is mandatory in any car with a modified floor or
rocker box within the roll-cage uprights (excluding 6 square feet of
transmission maintenance opening). Rocker bar must be installed
below and outside of driver’s legs and must tie into the main hoop,
the forward hoop, frame, frame extension, or side diagonal. Rocker
bar may not tie into swing-out side bar support. If rocker bar ties
into side diagonal more than 5 inches (edge to edge) from forward
roll-cage support or main hoop, a 1 5/8-inch x .083 CM or .118 MS
brace/gusset is mandatory between the diagonal and forward rollcage
support or main hoop.
“D” bar installation for full-bodied cars: For front-wheel-drive cars,
with complete OEM floor (from the firewall to the rear of the trunk)
and rocker/sill boxes, the 1 1/4-inch x .058-inch CM (.118-inch MS)
“D” bars (when required; i.e., when the main hoop is not welded to
the frame) may be welded to a 1 5/8-inch x .083-inch CM (.118-inch
MS) crossmember welded to the rocker/sill box via conventional 6-
inch x 6-inch x 1/8-inch-thick plates. For rear-wheel-drive cars, with
neither a frame nor subframe connectors, but with complete OEM
floor (from the firewall to the rear of the trunk; exception: the rear
inner wheelwells may be tubbed with steel or aluminum), the 1 1/4-
inch x .058-inch CM (or .118-inch MS) “D” bars may be welded to
conventional 6-inch x 6-inch x 1/8-inch formfitted/contoured plates
attached to the driveshaft tunnel. Otherwise, the “D” bars must be
attached to frame, subframe, or subframe connectors.
Swing-out side bar permitted on OEM full-bodied car 8.50 e.t. and
slower. The following requirements (a through d) apply:
a. 1 5/8-inch O.D. x .083-inch CM or .118-inch MS minimum.
Bolts/pins must be 3/8-inch-diameter steel, minimum and in
double shear at both ends.
b. Male or female clevis(es) permitted. Male clevis must use two
minimum 1/8-inch-thick brackets (CM or MS) welded to each rollcage
upright; female must use minimum 1/4-inch-thick bracket
(CM or MS) welded to each roll-cage upright. Pins must be within
8 inches of the vertical portion of both the forward and main
hoops. A half-cup backing device must be welded to the vertical
portion of the main hoop (inward side) or the upper end of the
swing-out bar (outward side), minimum .118-inch wall (CM or
MS) extending at least 1 5/8 inches past the center of the pins. A
clevis assembly using a minimum .350-inch-thick male
component and two minimum .175-inch-thick female components
may use a 1/2-inch-diameter Grade 5 bolt and does not require a
half-cup backing device.
c. Sliding sleeves of 1 3/8-inch x .083 CM or .118 MS, with
minimum 2-inch engagement, are permitted in lieu of the upper
pin/cup.
d. All bolt/pin holes in the swing-out bar must have at least one-hole
diameter of material around the outside of the hole.
Steel-bodied pickup trucks (7.50 seconds and slower), roll cages
are permitted with no back braces if the roll cage satisfies SFI
25.1E, 25.2, 25.4, or the roll cage consists of a 4-point (door car)
cage with a complete SFI 2.4B, 2.5B, 2.6, 2.7A dragster, SFI 10.2,
10.3 altered, or SFI 10.4 street roadster roll cage/driver’s
compartment incorporated into and attached to the 4-point roll
cage. An upper windshield bar is mandatory.
Non-steel-bodied pickup trucks (7.50 seconds and slower), roll
cages are permitted with no back braces if the roll cage satisfies
SFI 25.1E, 25.2, 25.4, or the roll cage satisfies the requirements for
SFI 2.4B, 2.5B, 2.6, 2.7A dragster, SFI 10.2, 10.3 altered, or SFI
General Regulations
20.26 Section 20 - General Regulations
10.4 street roadster roll cage/driver’s compartment. No 4-point
(door car) cage is required and no upper windshield bar is required.
On all cars requiring a roll cage, if the OEM firewall has been
modified (in excess of 1 square foot for transmission removal, not
including bolted in components) a lower windshield or dash bar of 1
1/4 x .058-inch 4130 chromoly or 1 1/4 x .118-inch mild steel is
mandatory connecting the forward cage supports.
All joints indicated as tube-to-tube joints/intersections must be
fabricated by properly notching the components to fit with minimum
clearance unless otherwise noted. Crushing the end of a tube to
oval in lieu of properly notching/fitting the tube is not acceptable.
Welding a plate to the side of one tube and butt welding the other
tube to the plate surface in lieu of properly notching/fitting the tube
is not acceptable.
For Sportsman full-bodied cars that require a roll cage (7.50
seconds and slower, including cars inspected to SFI 25.4 or 25.5): If
the windshield/roof bars are interrupted by the dash bar, then either
the entire dash bar must be minimum 1 1/2-inch x .058-inch CM
(.118-inch MS) or the entire dash bar must be minimum 1 1/4-inch x
.058-inch CM (.118-inch MS) and must be braced with gussets to
both the upper and lower sections of each windshield/roof bar. The
gussets may be either 1.75-inch x 1.75-inch x .110-inch (with one
1/2-inch-diameter and two 5/16-inch-diameter holes maximum)
4130 CM or MS plate (triangle shaped) or 3/4-inch x.049-inch CM
(.118-inch MS) tubing at least 4 inches long. An interrupted
windshield/roof bar is defined as one that has been completely
severed into upper and lower sections/pieces and then the
sections/pieces are welded to the dash bar.

[ericnova72]

I can't seem to find it in the rule book at the moment, or remember if it was an inspector who told me, but the rear braces to the main hoop can be up to 4" down the side of the main hoop from the top bar and still be legal. You might PM Techinspector here on this board to fill you in, he techs at Firebird in Arizona.

EDIT: I just noticed it says 5" in the diagram above

[techinspector1]

"Rear braces must be of the same diameter and wall thickness as the roll bar and intersect with the roll bar at a point not more than 5 inches from the top of the roll bar."

This part of the rule is in General Regulations 4:10, Roll Bar.

The whole idea of the rear braces, also called "C" bars, is to prevent lozenging forward or rearward of the main hoop, also called the "B" bar. Maximum protection will be afforded with the C bars intersecting the B bar right up at the roof.

[techinspector1]

Originally Posted by carnahan

i bought a 95 s-10 with a 10 point cage. the bars that go to the rear of the truck do not come off the top hoop. they come off the crossbar just below the top hoop, kinda behind the back of the seat. does anybody know if the cage will certify NHRA that way or do they have to come off the top hoop. thanx for the help.

What I did and have seen many other truck owners do is to add the C bars through holes cut in the back of the cab, then finish the holes off nicely with grommets or window rubber. The crossbar that goes across the cab right behind the seat is for the mounting of the shoulder belts. You might also fashion some gussets for the C bars. You'll need 2 gussets for each bar (4 total), 1 3/4" minimum on the long unwelded side of the gussets. The reason for this is that the welder will never be able to get his torch all the way around the C bars to weld them 360 degrees because of the proximity of the roof.

One more thing....as you stand at the side of the truck, the B bar is vertical or zero angle. The C bars must be at least 30 degrees or more divergent from the zero angle of the B bar.

The only way to side-step installation of the C bars on a pickup truck is to build a full peripheral cage, then build a funny car cage inside that. I've seen a couple of trucks at National events like that.

[carnahan]

okay, think i have my answer. truck is still in progress and i wanted to get that clarified before i go any further. i just found this wedsite and now i know where to come for good info. thanx for the help.

[carnahan]

one more question. overdriv asked how fast i plan on going. im shooting for high 10s to low 11s. plan on driving on street, hints the original question. would like to not see the bars out the back glass. is that still to quick to worry about tech. not really a big deal, i think i'll just go ahead and put them out the back glass. that way i won't have to worry about it. thanx again.

[ericnova72]

Roll bar is required at 11.49 ET, so you need to worry about it. It will not pass if the rear bars meet the main hoop too low.

Even if you don't intend to go that fast, it still won't pass. A roll bar/cage installed in a car too slow to even require one still has to be installed per the rules, otherwise it is considered a safety hazard. Screwy... I know, but that is how it is.

[Overdriv]

The guy that installed my roll cage brought the rear bars out of the top of the rear glass opening then down to the frame rails. It is mostly a street cruiser but we do race it on occasion. He said it would pass NHRA spec to 8.50. The back window is Lexan.

Go here to take a look at mine. If you would like, I have other pictures that might show it better.

[carnahan]

wow nice truck. looks like you did a good job and did it right. no more pics needed thanx anyway. i was just trying to get away from having to use lexan for the back. not a big deal, plenty of nice trucks out there using it, like yours for instance.

[Overdriv]

I tried to find someone to just notch my back glass, but no one was interested in trying it. Lexan is really easy to work with, just leave the covering on it till you are done fitting it.

Good luck.

[carnahan]

i wondered about nothcing glass didn't know if it could be done. friend of mine does auto glass for a living. might see if he wants to try.

thanx for the info.

[2wheeler]

You can't notch your backglass because it's tempered

[carnahan]

yeah thats what i figured