1/4 mile set up, question about roll cage

I want to do some 1/4 mile runs this comming summer, but I was told I would need a roll cage. So I started looking into roll cages, the two I found in the net are just plain ugly. It also looks like a massive undertaking to install one. Any ideas?

u only need a roll cage if you're runnin 11 seconds or less. But if u are then yes it will be a hell of a task!!!

Originally Posted by howie

u only need a roll cage if you're runnin 11 seconds or less. But if u are then yes it will be a hell of a task!!!

with 17's and slicks I am sure I will be below 11 seconds..well that takes care of that..I seen a couple more pics on google and you have to gut the car to do it..no 1/4 mile runs for me..

if you break 11.00, you'll be setting an e46 record... good luck
I recommend kirk bolt-in cages, I've installed one in a few hours.

Originally Posted by bluejeansonfire

if you break 11.00, you'll be setting an e46 record... good luck
I recommend kirk bolt-in cages, I've installed one in a few hours.

2nd on the kirk bolt in cage. I think that would be the easiest solution.

Originally Posted by bluejeansonfire

if you break 11.00, you'll be setting an e46 record... good luck
I recommend kirk bolt-in cages, I've installed one in a few hours.

Now that looks more like it..Yup I am hoping to break below the 11.00 mark, it seems like traction has always been an issue with hpf cars. I think with some slicks and nice tall side walls that will flex for me I should be able to do it..

below 11s would be sick for that car...u must have a sh1tload of $$$ in the suspension, drivetrain and pretty much everywhere else!?

ROLL CAGE{reprint}

Mandatory in all cars running quicker than 10.99 seconds or faster

than 135 mph, or per class requirements. Cars with unaltered

firewall, floor and body (from firewall rearward, wheeltubs

permitted) running between 10.00 and 10.99, roll bar permitted in

place of roll cage, or per Class Requirements. Cars with altered

firewall, floor faster than 11.49 must have rollcage and window net.

All cage structures must be designed in an attempt to protect the

driver from any angle, 360 degrees. All 4130 chrome-moly tube

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

tube welding must be approved MIG wire feed or TIG heliarc

process. Welding must be free of slag and porosity. Any grinding of welds prohibited. Additionally, roll cage must be padded anywhere

the driver's helmet may contact it while in the driving position.

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

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.

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, 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 roll-cage support or

main hoop.

I see that you're in seattle....http://www.position1.net/ Hit those guys up. I've seen a few of their cages when I lived in OR, and they looked great. Buying a prefabbed cage has it's advantages, but custom cages are where it's at when you're doing 6 points or more.

Custom cage work is expensive, but when you're talking about safety it's worth the $$. Plus getting a custom cage can make things more 'ergonomically' correct.

Looks like you only need a roll bar... the Kirk 4pt bolt in would be fine..

We will be designing a custom roll cage for our drag car Derek. That will be a 10 pt cage. However, we could build a rear 6 pt section for your car. I'm not sure if we will sell the metal pre-cut with all of the mounting plates, but it may happen.

Chris.

Be careful with the bolt in rollbars, an Autopower one recently punched through the floor of a Mustang during a DE at Hallett. You'll also completely lose the ability to carry passengers in the back seat, which is a problem if you have a little person who needs a car seat.

I'm meeting with my local custom cage builder so he can inspect my car. He's suggesting a rollbar that mounts to the rockers and then the downtubes mount to the rear subframe. All with large sandwich plates. He's suggested those areas as they're multi layer steel vs the floor and wheel wells, which are single layer. All the bolt in commercial rollbars (Kirk, Autopower, etc) mount to the floor and wheel wells.

Hit me up on pm, I've spent a lot of time looking into this...

Originally Posted by docwyte

Be careful with the bolt in rollbars, an Autopower one recently punched through the floor of a Mustang during a DE at Hallett.

Was the driver ok in that pic?

Originally Posted by BMW_Matt

Was the driver ok in that pic?

yes, both passenger and driver were completely uninjured, by tremendous luck.
personally, I would run a bolt-in cage such as a kirk, which does fulfill the requirements. It also comes with very sturdy sandwich plates. if you want further reinforcement, weld it to the floor and a weld a a box tube from point to point (on each side) on the floor to keep it from punching through by giving more surface area, you can even weld those beams to the floor for further stiffness.

The bolt in cages will do a little better as they have more area to disperse the load, but they're still mounting to the weakest points of the car.

If you're going to run a cage, you really need to go with a custom welded in cage.

Come up to Mission raceway, lots of WA folks do it! It would be awesome to have more M's racing next season. There's also a local BMW performance shop (Miller Performance) that does discounted dyno pulls before the races.

honestly op I would just take it to the track and run it 1st to see what it does. Tell them it will run 13s and then get kicked off the track. Then if u do run 11 or less then worry about rollcage

Originally Posted by howie

honestly op I would just take it to the track and run it 1st to see what it does. Tell them it will run 13s and then get kicked off the track. Then if u do run 11 or less then worry about rollcage

Exactly. Or if you're feeling lucky just lean on the brakes at the 3/4 mark and see what that nets you. Next run wait a little longer etc.

Originally Posted by howie

honestly op I would just take it to the track and run it 1st to see what it does. Tell them it will run 13s and then get kicked off the track. Then if u do run 11 or less then worry about rollcage

Yeah, they don't put the safety requirements in place to protect drivers or anything, its because they want to be mean.

If the car is fast enough to justify the NHRA safety equipment/options, and you're pushing it that hard, street or track its not a bad idea to meet the reg's, your life may depend on it.