Author Topic: 8 point roll cage  (Read 15958 times)

Offline lincoln welder

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8 point roll cage
« on: January 22, 2009, 07:03:24 pm »
Hey guys, The fed-ex man just droped off my latest brain storm, an 8 point cage from s & w race cars for my 83 c-10 shortbed. Has anyone had experience installing one of these puzzles and does anyone have pics of how to attach it to the frame. Im trying to meet NHRA rules for full frame cars running faster than 11.49 1/4 mile. Thanks, Troy
72' blazer 8" lift ZZ4 350
83' 2wd step side 489 BB
06' 3500 duramax
08' radio flyer 16" lift,ladder bars &custom interior.

Offline HAULIN IT

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Re: 8 point roll cage
« Reply #1 on: January 22, 2009, 07:56:00 pm »
Troy, based on the original design of our trucks (narrow framerails) some additional work is required. As with any full frame vehicle, you want to remove the rubber cab bushings & either replace them with solid ones (easiest) or eliminate them & bolt/weld the cab & frame, then adjust the other body panels accordingly. Some "outriggers" (4) will need to be made from the frame & rocker panels to sit the hoop & front of the door bars on. Even though our trucks fit the "Full Frame" category, these outriggers welded to the frame should pass tech down to 10.00 (with the stock floor & firewall). Here is a section from an IHRA rulebook:  Mandatory in all cars running 11.49 or quicker, or per class

requirements. All roll bars must be within 6 inches of the rear or

side of the driver\'s head, extend in height at least 3 inches above

the driver\'s helmet with driver in normal driving position, and be at

least as wide as the driver\'s shoulders or within 1 inch of the

driver\'s door. Rollbar must be adequately supported or cross-braced

to prevent forward or lateral collapse. 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. Sidebar must be included on driver\'s side

and must pass the driver at a point midway between the shoulder

and elbow. Swing-out sidebar permitted. All roll bars 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 vehicles with OEM frame (i.e. pickup truck where body

bolts to framerails) must have roll bar welded or bolted to frame.

Installation of frame connectors on unibody cars does not

constitute a frame; therefore, it is not necessary to have the roll bar

attached to the frame. Unibody cars with stock floor and firewall

(wheeltubs permitted) may attach roll bar with 6-inch x 6-inch x

.125-inch steel plates on top and bottom of floor bolted together

with at least four 3/8-inch bolts and nuts, or weld main hoop to

rocker sill area with .125-inch reinforcing plates, with plates welded

completely. All 4130 chrome moly tube welding must be done by

approved TIG heliarc process; mild steel welding must be done by

approved MIG wire feed or approved TIG heliarc process. Welding

must be free of slag and porosity. Any grinding of welds prohibited.

Roll bar must be padded anywhere driver\'s helmet

may contact it while in driving position. Adequate padding must

have minimum 1/4-inch compression or meet SFI Spec 45.1.


And this:
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.
 This should get you started. Remember the seat back must be bolted to the rollbar & also the approved seatbelt. Lorne

Offline lincoln welder

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Re: 8 point roll cage
« Reply #2 on: January 23, 2009, 08:30:07 am »
Thanks for the info,Sounds like youve been down this road already. Are you allowed to have a connection point from the back brace to the main hoop to ease gettin the window in?Your pic looks like your gettin it done pretty good. What kind of set up are you runnin(engin, trans, rear, suspension.) Im intrested in anyone who drags these trucks on a regular basis for input.thanks Troy
72' blazer 8" lift ZZ4 350
83' 2wd step side 489 BB
06' 3500 duramax
08' radio flyer 16" lift,ladder bars &custom interior.

Offline HAULIN IT

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Re: 8 point roll cage
« Reply #3 on: January 23, 2009, 10:27:26 am »
Tony, Yes, you can have "Swing out bars" as long as the bar (when closed) is following the rules (between shoulder/elbow, ect.). To be legal, both ends must be bolted, it can not be quick pinned. Some digging in the rulebook or online will show some other details.
 My wife's truck is pretty much a daily driver in nice weather. It has a fairly basic Olds 455, 4L60 Transmission & a 9" rear with 3.50 gears. Her best pass to date is 11.93 @ 111mph with a 1.64 60ft.
 If you do a search in Member's Projects...type in "Rear end swap", you can see my rear suspension set-up. There are some video's I posted in the Performance section... type in "Dragstrip video", I haven't had a chance yet to post the last trip.   
Any other questions...Ask, Lorne   

Offline autorepr

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Re: 8 point roll cage
« Reply #4 on: January 23, 2009, 01:13:37 pm »
I think Haulin It covered it but one thing I'll add is make sure you hook your seat belts and seat both securely to the cage. There was a guy around here that left his seat bolted to the floor and attached the belts to the roll cage and when he smashed the car the body shifted and the cage didn't. The belts nearly cut him in half! He lived but he wasn't liking life for a while.
UH-OH  I'M GONNA NEED A BIGGER BANDAID!!!!!

Offline lincoln welder

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Re: 8 point roll cage
« Reply #5 on: January 23, 2009, 08:27:51 pm »
Man Lorne,that thing launches hard. 11.93 is nothin to sneeze at. If this thing will show me 11.50's then ill be tickled. Im going to run a 9" with 4.11 gears and a 30" tire. th 350 and a 489 built by Davis race engines out of west chester. He built the motor to handle NOS,so if she dont scare the BE-Jesue outa me im gonna give her a snort. Thanks for all the input guys. Ill post some pics soon. Troy
72' blazer 8" lift ZZ4 350
83' 2wd step side 489 BB
06' 3500 duramax
08' radio flyer 16" lift,ladder bars &custom interior.

Offline HAULIN IT

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Re: 8 point roll cage
« Reply #6 on: January 24, 2009, 06:33:14 pm »
Troy, You shouldn't have much trouble reaching your goal. Are you building the truck for strip only? What are you using for tires? One thing you want to keep an open mind about is gear ratio...many large engines simply don't want or need allot of gearing. I know of several vehicles over the years "made faster/quicker" by using less gear. One thing about gearing is, you will know for sure when you have taken too much out. A couple years ago, I had a 12 bolt w/3.40 gears in the truck...it would go between 12.40@109 to 12.60@107 depending on the weather & track. When I built the 9", I put together a 3.70 gear...the truck went 12.40@107 to 12.60@105. Doing some playing with a speed calculator or two, I decided to try the 3.50's...11.90's@111 to 12.30's@109. In my brother's car (460 Mustang), we went from 3.70 to 4.11 w/ an 1" taller tire (which should have been the same, but with a bigger footprint) the car slowed a couple 10th's. In preparation to spray it, we put in 3.50's & picked up a steady 2 10th & mph, but when going to 3.25's, the bottom fell out BIG time (lost a half second). In my friends Camaro (427 small block) he gained several 10th's & mph going from 4.88's to 4.11's, also in his dad's 502 Monte, same thing...a couple 10's & mph going from 4.56's to 4.11's. 30" tires are pretty big, but just keep this in the back of your mind. Lorne 

Offline Captkaos

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Re: 8 point roll cage
« Reply #7 on: January 24, 2009, 10:47:35 pm »
I agree with Lorne.  Higher is not always better.   When my 454 was running I went from 4.10's to 3.42's  It was noticeably faster.  I didn't take it to the track beforehand though.

Offline lincoln welder

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Re: 8 point roll cage
« Reply #8 on: January 25, 2009, 02:06:21 pm »
Thanks again guys. I'm planning in running this thing on the street a good bit.Car shows etc. I'm not to the point of buying gears yet but I see where your comming from.I know that the torque of the 489 will compensate for a taller gear plus I don't want to run out of rpm before I reach the traps. Ill do more intensive research into that when I get closer.As far as tires go street tires are MT Sportsman 31 x 16.50 x 15 on 14" wide truck rallys. Strip tires I'm not sure of yet,prob will go with a full blown slick. Now as far as my previous post about the traction bars goes all that changed on Saturday. Was at a swap meet unloading some of my junk for cash and stumbled on a S&W complete ladder bar setup.Cross members to coil-overs. So looks like as soon as I get my housing the leaf springs are history. Should take care of gettin it to hook.  Troy
« Last Edit: February 18, 2009, 10:35:46 am by Captkaos »
72' blazer 8" lift ZZ4 350
83' 2wd step side 489 BB
06' 3500 duramax
08' radio flyer 16" lift,ladder bars &custom interior.

Offline team39763

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Re: 8 point roll cage
« Reply #9 on: February 18, 2009, 10:18:49 am »
Any updates on this?