Bolt-in half cage choices

[shreyas]

Is there any consensus on which bolt-in half cage is the “best” out there. I’ve heard negative things about the Kirk, autopower, and studio rsr cages which is making me lean towards Bayside Fabrication. Anybody have experience with his cages?

Also see a lot of options across the pond such as gosling racing, safety devices, sw Motorsport, and psdesigns.

[9kracing]

I'm still looking for a Raven cage

[shreyas]

I'm still looking for a Raven cage

Heard of those but it seemed like they didn’t provide adequate roll over protection. My car is dual-duty street/track so I want the safety aspect as well.

[Gt4]

you won't have roll over protection with a bolt-in roll bar bolted into 20gauges sheet metal floor pan

[Nate047]

I have a Bayside fab bar that I’m going to sell, it’s built well from what I can see and Ben is pretty quick to build and good at communicating. Just make sure a bolt in bar is really what you want, and be honest with yourself about what you’re buying and what it will do for you in a crash.

[Estoril]

Anything worth doing is worth doing right.

[L0okitzRaj]

Anything worth doing is worth doing right.

What would the do it right cage consist of? Full weld in with door bars, and apillars?

[Estoril]

What would the do it right cage consist of? Full weld in with door bars, and apillars?

No, a weld-in half cage.

That is assuming that its a DE car.

[bigjae46]

No, a weld-in half cage.

That is assuming that its a DE car.

How is a weld in cage significantly better than a bolt in cage? A weld in cage welds to the same sheet metal that a bolt in cage bolts to?

I think a weld in cage adds little to no value beyond a bolt in cage. In fact, I see a weld in cage making the car harder to sell with very little benefit. First, both are essentially harness bars. There is a good chance you will be cutting out the weld in cage if you want to go to a full cage. First, the roof has to come off to weld in the forward and roof bars. Most cage builders will not add on to a cage that didn't build so you're stuck going back to the same builder. That's not a big deal, right? What if the cage builder has a 6 month backlog?

My point of view is it that changes to safety systems will always be a compromise. You must understand the potential consequences and ask yourself if you're OK with that.

For example, in the US we drive with the windows down. The most common causes of injury or death in a rollover is the head or body parts (arms) coming into contact with the pavement (if the car lands on its side) or interior surfaces/objects. Shouldn't we all have window nets in our cars no matter what?

The roof caving in rarely is the direct cause of injury - its bodily contact with the pavement or interior surfaces. The issue with a rollover is if the car rolls multiple times there are multiple impacts which reduce the effectiveness of safety systems with each impact. Airbags only provide protection on the first and maybe second impact. This is research from the National Safety Council. Also there is a Schroth video floating around that talks about this.

In the end, I think a half cage WITH a FIA containment seat, 6pt harness and a HANS device is the best overall compromise short of a full roll cage. I chose a full cage because it is the side impacts that scare the shit out of me. Saw someone hit the end of the armco sideways at 80mph on the pass side with an instructor. The side of the car was caved in and the instructor was seriously injured.

[Estoril]

How is a weld in cage significantly better than a bolt in cage? A weld in cage welds to the same sheet metal that a bolt in cage bolts to?

I know that you are aware that its is the attachment of the bolt-in half cage that is the issue (that of course assume the design geometry, tubes and welds are 100% - which is a far cry from certain). Pretty much every bolt-in I have seen was done in the name of: (1) limiting work (and therefore cost), (2) cost, (3) ease and speed of of installation and (4) ability to quickly and easily remove it when the car is sold. That means that >90% of these installations just bolted to the BMW floor.

Yes - one should weld-in boxes or other spec plates - but very few people do that for the 4 reason noted above.

You and I have been in this game long enough to see the ghetto safety rigs that were done in the name of saving money. I have refused to instruct in cars with such shortcuts. Fine for someone else's neck. Not for mine. YMMV.

What the OP does with his own neck is his business. I'm not here to legislate.

I won't go down the path of window nets and full cages for HPDEs etc for reasons that should be obvious.

[Gt4]

How is a weld in cage significantly better than a bolt in cage? A weld in cage welds to the same sheet metal that a bolt in cage bolts to?


Depends how it's built and where it attach. Most bolt-in roll bars are drilled into the floor pans and rear wheel wells. When I was building rollbars/rollcage, I would make base plates for main hoop that were also weld to the rockers side and fuel tank wall and get the diagonal from main hoop to rear shock towers.

Also it's doable to have a rollbar and weld a full rollcage couple years later. Did it couple times

[bigjae46]

I know that you are aware that its is the attachment of the bolt-in half cage that is the issue (that of course assume the design geometry, tubes and welds are 100% - which is a far cry from certain). Pretty much every bolt-in I have seen was done in the name of: (1) limiting work (and therefore cost), (2) cost, (3) ease and speed of of installation and (4) ability to quickly and easily remove it when the car is sold. That means that >90% of these installations just bolted to the BMW floor.

Yes - one should weld-in boxes or other spec plates - but very few people do that for the 4 reason noted above.

You and I have been in this game long enough to see the ghetto safety rigs that were done in the name of saving money. I have refused to instruct in cars with such shortcuts. Fine for someone else's neck. Not for mine. YMMV.

What the OP does with his own neck is his business. I'm not here to legislate.

I won't go down the path of window nets and full cages for HPDEs etc for reasons that should be obvious.

Yeah, I've seen some shit! lol

I will agree that the Kirk roll bar makes me question whether the wheel well is the right place for mounting (it's not). I've seen a nice 4pt roll bar - forget if it was TC Designs or Fall Line. I really don't see the point of a half cage - which is a glorified harness bar - when our cars have the Schroth quick fit option.

[eacmen]

When I got my half cage welded in the builder designed it so he could extend it later on.

The car came with a bolt in cage and I wouldn't trust that shit. It was just drilled holes in the floor and wheel well.

I think an often overlooked component is seat mounting. Cage builder welded in a 1inch square tube H frame for the seats and sub straps to mount to. When you think about it the seat mounts would experience significant forces with 200+lbs in the seat in a 10+ G impact.

[bigjae46]

When I got my half cage welded in the builder designed it so he could extend it later on.

The car came with a bolt in cage and I wouldn't trust that shit. It was just drilled holes in the floor and wheel well.

I think an often overlooked component is seat mounting. Cage builder welded in a 1inch square tube H frame for the seats and sub straps to mount to. When you think about it the seat mounts would experience significant forces with 200+lbs in the seat in a 10+ G impact.

What happens if you move? Or the builder goes out of business? That has burned more people than you think.

I would not trust any half cage to anything beyond securing the harness shoulder straps.

I’d be less worried about the seat mountings ripping out of the floor. If anything just stitch weld the mountings. I’d be WAY more worried about just about ever floor mount adaptor I’ve seen. So shitty aluminum ones that have 1/8 of soft aluminum under the bolt head. Then the area galls each time you torque the fastener.

This is my floor mount - 3/4” thick T-6061 aluminum. Bolt holes are counter sunk 3/8” so there is 3/8” of aluminum under the bolt heads. And this cost $100 to make. Just need a forstener bit to countersink the holes.