how to fasten boltin roll cage

[mickster8888]

just bought a bolt in roll cage and was wondering what type of hardware i'll need to bolt it in? the cage is used and i can't find any info on how to secure it. bolts and washers? thanks in advance.

[Whtnkls911]

First try and find who made the cage, then call them, usually can sell you the bolt package. If you cannot find markings on who made it, post a picture, someone will recognize it. If not, go to a good hardware store that has metric hardware and use grade 8.8 or better hardware.

[Formerly Steve Wilkinson]

A bolt-in roll cage??? I assume you mean a bolt in roll bar. Big difference. Typically bolt-in roll bars use the existing seat-belt mounting pads. A cage is welded in and becomes part of the car's total platform.

[Zeke]

Well, you don't have to use metric and grade 8.8 ain't anything special. Grade 8 SAE is, though.

Some roll bars come with bolt up door braces that can be removed for street driving. We do need to see some pics. However, you will probably end up bolting to where it rests when installed. For instance, the bar that came in my car was bolted to the floor in back of the seats and bolted to the top of the wheel wells. IOW, it was not much more protection than the car itself, just a place to mount harnesses. And, it had a bolt up cross brace and harness bar that could be removed for street driving. No way was it gonna bolt up to the rocker channels or rear seat belt mounts w/o a ton of work.

It made the car a lot less useful for street driving and I sold it.

[ks2_motorsports]

you want to use AN bolts in this application, Grade 8 have a higher shear rating but they don't have the elastic properties of a proper AN bolt, you don't want these bolts to break.

Also key is making sure you have no threads mounted in shear you want the shoulder of the bolt to protrude the hole of the backing plate and use washers to provide the proper grip for the nut and bolt.
AN bolts come in so many lengths that you can get the right grip length without having to use a stack of washers, they even have half height washers if needed

[rattlsnak]

standard practice is to have the bolts come up through from the underneath, with the nuts on the top, or inside of the car.

Steve, yes, there are MANY cages that are bolted in, not just roll bars, and not all roll bars mount to existing belt holes. Basically a roll bar, is the hoop portion behind the driver, and a cage is the hoop portion plus the front 'half' that goes forward to the A pillars.

[boba]

Before you mount this be sure it will pass Tech for intended use.

A welded in rollbar or cage can provide protection......

a boltin can provide a look.


Not a fan of bolt in.

[mede8er]

My TRE Clubsport bar has all the bases covered.....bolt into existing rear seat belt mounts, weld a pre-drilled plate to the floorpan and bolt the front mounts to that welded plate....bar can be easily removed for maintenance purposes....

[barney911rs]

mick,

update your profile with your location and perhaps if there is someone near you with experience, they take a look and see in person.

[mickster8888]

thanks for all the info. it's an autopower full cage. i want to make sure i can live with it on the street before making anything permanent. i kinda figured that the bolts would be of a certain spec. i'm not going for a "look" i'm going for protection as i've been pushing the limit on some isolated roads and would like some added protection should push the 930 too far. i figure even a boltin is better than nothing at all. if i find it not that much of an issue for everyday use than i'll weld it in. thanks again for the info.

[barney911rs]

you need to be very careful with a cage in a street car. Remember you will not be wearing a helmet, and the bars are a lot harder then your naked head. Make sure they are as far away from your head as possible and put plenty of padding on any bar you might even remotely come into contact with with body parts (hands, feet, arms, legs, head). In a crash you will move around a lot inside the car.

[911st]

There are plates that back up the bottom side under the car and in the rear fenders. Get the cage where it fits best. Might have to move it around till it it works right. As noted, most bolts go up. You should be able to drill enough holes downward from inside to start and hold the cage in place. Then bolt it up and drill the holes where there is not enough clearance from inside, up from the bottom using the bottom plates as a guide. Where it mounts the the rear fender wells, it will likely distort the sheet metal to fit the cage when tightened as it dose not often fit nice and square.

At least, that is my guess.

[mickster8888]

911st, thanks as that was what i was looking for. as for hitting head on the cage, i didn't think of that. such a simple concept that i never thought of. i'll pad the bar in the appropriate places. thanks for the info guys.

[Formerly Steve Wilkinson]

Padding--and of course you'd use the expensive stuff ($18 a foot last time I bought some) rather than Home Depot pipe insulation, which way too many Honda hooners use--will do you little good without a helmet. It's not intended to cushion a naked skull.

I'm a volunteer EMS worker in my second life, so I get to see how much bodies can move in a serious MVA. Sitting in the driver's seat of your 911 and "imagining" where your head might go in a crash is of far less use than you might think, five-point harness and all: you can hit that damn thing all sorts of places.

You won't be killed by rolling your 930 while overcooking it on a back road, you'll buy it when the woman in the Escalade rear-ends you while she's on her cellphone and you're stopped at a red light. Your head and that roll bar will quickly meet, and no amount of padding will help.

Okay, I say this as somebody who drives around with a bolt-in DAS rollbar in my car--thoroughly padded, of course--because it's just too much of a pain to take the seats out and then remove it between DEs. But I'm done with DEs, and this spring, it comes out permanently. (Anybody want it?)

Think twice about using a rollbar/roll cage on the street. Especially a cage, which has way more places your head can hit it in an MVA.

And rattlsnak, I do know the difference between bars and cages. I just don't consider a "bolt-in roll cage" to be either one.

[boba]

Not to be too much of a killjoy, but get a mellon at the grocery and a baseball bat wraped with dense foam and take a good wack at the mellon......

Not intended for use without a helmet.

OK, you will be using a 5 or 6 point harness, find some in car video of how much stretch there in in your neck and body under high G impact.

Just dont want people to get hurt because they did not understand what could happen.

[rfn026]

You have to be insane to drive on the street with a full cage in the car.

Why bother going to the store to buy a mellon? The first time your un-helmeted head hits that cage you'll be your very own veggie.

Richard Newton
Porsche Race Car File

[mickster8888]

i really never knew that it could be an issue. it's too late now as the cage is being delivered on monday. hopefully the race seat, harnesses, and padding give me some protection. kinda weird that you need protection from something that's supposed to protect you. anyway, thanks for the feedback as now i have food for thought.

[Formerly Steve Wilkinson]

Too late? Strange rationale... Sell the thing.

The only thing that will make you somewhat safe is a helmet. Race seat, harness and padding will help in a 20-mph accident.

[tabasco]

I've already thought about where my head could go in a crash, and you don't need a rollcage to be scared. Look at the door frame, windows, seatbelt mount up there, what about the sunroof rails and hardware nicely hidden behind the headliner ? (for the unlucky ones like me that still have a sunroof)

My point is, it's not safe with a rollcage, the cage will be definitely a lot closer, but it's not very safe without it to begin with. If you're going to hit the rollcage you'd hit whatever is behind the rollcage anyway. Is a padded rollcage more dangerous than an unpadded door frame ?

The rollcage will also help against intrusion.

I would definitely insist on a good & tight race seat (not reclinable !) if you're to drive with a roll bar or cage.

[Formerly Steve Wilkinson]

Hey, go for it and have a nice day.