I can't seem to find anything that's proper, like a Hard Dog for a Miata.
Only Chrome-Moly junk that doesn't even have a harness bar.
I can't seem to find anything that's proper, like a Hard Dog for a Miata.
Only Chrome-Moly junk that doesn't even have a harness bar.
Hit up Moti at Blackbird Fabwerx. If he doesn't have one in his product line, you might spark his interest to create one. Bonus points for helping find him a car to develop it on.
My car was the mule for this:
http://tunersmotorsports.com/?p=2748
No diagonal and not DOM tubing.
That may suffice for some people, but not me.
Keith Tanner wrote: Hit up Moti at Blackbird Fabwerx. If he doesn't have one in his product line, you might spark his interest to create one. Bonus points for helping find him a car to develop it on.
Good idea! Thank you sir.
I've had one of Moti's bars in my (now bgkast's) Miata and I was very impressed with it. If I had a Frisbee I certainly wouldn't hesitate to get him to fab up one if he hasn't got an off the shelf option.
Maybe I can talk him and someone close to him into it.
I'd have no problem, but he is in the Bay Area IIRC and I'm in OK.
Sounds like a good excuse for a fun road trip in your new awesome car. 
BoxheadTim wrote: I've had one of Moti's bars in my (now bgkast's) Miata and I was *very* impressed with it. If I had a Frisbee I certainly wouldn't hesitate to get him to fab up one if he hasn't got an off the shelf option.
I agree,it's a very high quality piece.
z31maniac wrote: Maybe I can talk him and someone close to him into it. I'd have no problem, but he is in the Bay Area IIRC and I'm in OK.
Unless he's moved, he's down in or near LA.
Get a nice custom 1/2 cage welded in. If you're sacrificing the back seats, you might as well do it properly.
http://tunersmotorsports.com/?p=2748
Is that an optical illusion, or do the vertical members of the main hoop have more than 180deg of bends in them? They look to pass through vertical on the way down to the floor, with a ( ) shape. In other words, pre-buckled for a roll-over.
z31maniac wrote: No diagonal and not DOM tubing. That may suffice for some people, but not me.
Dude what? That cage is DOM, all Chro-mo tubing is DOM tubing. You need to check on the wall thickness and ask them what filler rod and if the roll bar was normalized/tempered. If they used the same wall thickness required of a poor mans mild steel bar and used the correct filler rod and/or tempered it theres no downside here besides the price since 4130 DOM tube costs more than 1018 DOM tube per foot and requires more expensive filler rod and/or post welding heat treatment. 4130 cages and roll bars are better than 1018 because they're stronger and stiffer, unless they're built for a governing body like FIA which does still allow 4130 cages to weigh less.
Lets cover this again, all 4130 (Chromolly) tubing is DOM (Drawn Over Mandrel) and is more expensive and, when made properly, better than a standard mild steel (1018) DOM roll bar. Either option is better than a mild steel ERW (ElectRic Welded). I make a big deal about the proper filler rod and/or heat treatment with 4130 weldments because if its welded with the wrong filler and then not heat treated the weld will fail in the impact loading a cage will see in a crash, which is why a lot of regulating bodies have banned the use of 4130 in cages or at least no longer let 4130 cages be made of thinner wall tubing for less weight.
z31maniac wrote: No diagonal and not DOM tubing. That may suffice for some people, but not me.
I'm sure they could add a diagonal. For a dual use car, it would interfere with moving the seat all the way back. If you are 5'6" it wouldn't be a problem. I'm 6'3" so I need all the seat travel I can get.
Excuse my ignorance, but why would you want a roll bar in a non-convertible? For competition use, you'd need a full cage. For track days, you wouldn't need anything. Why go half way?
Yeah, to me there are only 2 good reasons to install a cage in a car with a roof (especially a modern car):
Gieb wrote: Excuse my ignorance, but why would you want a roll bar in a non-convertible? For competition use, you'd need a full cage. For track days, you wouldn't need anything. Why go half way?
I run a bolt in roll bar in my e36 M3, its the only way I would feel ok with a harness.
Slippery wrote:Leafy wrote:Leafy, When using Cro-Mo, can't you get away with a smaller diameter bar for the same strength? This one is 1.75" which i am sure is ok for regular steel, but might be overkill when using Cro-Mo.z31maniac wrote: No diagonal and not DOM tubing. That may suffice for some people, but not me.Dude what? That cage is DOM, all Chro-mo tubing is DOM tubing. You need to check on the wall thickness and ask them what filler rod and if the roll bar was normalized/tempered. If they used the same wall thickness required of a poor mans mild steel bar and used the correct filler rod and/or tempered it theres no downside here besides the price since 4130 DOM tube costs more than 1018 DOM tube per foot and requires more expensive filler rod and/or post welding heat treatment. 4130 cages and roll bars are better than 1018 because they're stronger and stiffer, unless they're built for a governing body like FIA which does still allow 4130 cages to weigh less. Lets cover this again, all 4130 (Chromolly) tubing is DOM (Drawn Over Mandrel) and is more expensive and, when made properly, better than a standard mild steel (1018) DOM roll bar. Either option is better than a mild steel ERW (ElectRic Welded). I make a big deal about the proper filler rod and/or heat treatment with 4130 weldments because if its welded with the wrong filler and then not heat treated the weld will fail in the impact loading a cage will see in a crash, which is why a lot of regulating bodies have banned the use of 4130 in cages or at least no longer let 4130 cages be made of thinner wall tubing for less weight.
Normally you use the same tube diameters as mild steel bars but thinner wall thicknesses. Pretty much no sanctioning bodies allow this anymore and dont list alternative tube requirements anymore, and the ones that do require you to submit forms and E36 M3 for approval or only approve cages installed by certain shops. So if the 4130 roll bar meets the rules for a mild bar it should be legal unless the sanctioning body explicitly bans 4130 bars and/or cages.
Leafy wrote:Slippery wrote: Leafy, When using Cro-Mo, can't you get away with a smaller diameter bar for the same strength? This one is 1.75" which i am sure is ok for regular steel, but might be overkill when using Cro-Mo.Normally you use the same tube diameters as mild steel bars but thinner wall thicknesses. Pretty much no sanctioning bodies allow this anymore and dont list alternative tube requirements anymore, and the ones that do require you to submit forms and E36 M3 for approval or only approve cages installed by certain shops. So if the 4130 roll bar meets the rules for a mild bar it should be legal unless the sanctioning body explicitly bans 4130 bars and/or cages.
shut, I tried to repond and deleted my post.
Thanks for the info!
z31maniac wrote: No diagonal and not DOM tubing. That may suffice for some people, but not me.
Seamless tubing with diagonal/X bracing between the rear supports is good enough for Hard Dog, in addition to pretty much every non-race/non-caged event sanctioning body...But not for you?
It's his safety, his car, he can want what he wants.
Agreed...I just find it more than a little ironic that his "proper" benchmark uses the same design elements as the one he's dismissing as inadequate.
Gieb wrote: Excuse my ignorance, but why would you want a roll bar in a non-convertible? For competition use, you'd need a full cage. For track days, you wouldn't need anything. Why go half way?
Don't overestimate the strength of even modern roof structures in a roll over impact. Just because something isn't required, doesn't mean having one won't be the difference between walking away and being carted away. I believe most sanctioning bodies even 'recommend' roll over protection at the parking lot autox level.
Life is a series of calculated risks. The more frequently you roll the dice, the more likely you are to benefit from taking additional precautions beyond the bare minimum.
Autopower makes good roll bars though not a tight fit like a nice custom weld in would be with the main hoop right up against the roof. Had an autopower bolt-in race rollbar in my track Camaro.
Driven5 wrote: Agreed...I just find it more than a little ironic that his "proper" benchmark uses the same design elements as the one he's dismissing as inadequate.
2000lb car with a tested and proven design vs a 2800lb car and a company I've never heard of.
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