Cole

Josh, not to pick on you. But how "tested" is the local "custom builder"?

Seems like they may have even less exposure and real testing than some of the mass produced units.

Welding can sometimes actually be the cause of a punch through, failed cage etc if not done properly, and a pretty weld is not always a good weld.

Having been very deep into the 4x4 industry for a few decades I can tell you that some of the "bolt in" stuff has held up MUCH better than some of the custom weld in stuff.

Any detailed specs and pictures of your cage?

What would one look for in a quality custom cage for one of these cars?

docwyte

Very well tested as the builder of my rollbar has built pretty much all of the cages for the spec 944 guys as well as the AI-CMC cars. But your point is well taken. If you're going to get a custom bar or cage built, make sure the person building it knows what they're doing!

My car has reinforcement plates and mounts to the rear subframe and rear frame rails. Fitment is far tighter than the autopower and it's not depending on single sided steel and a small backing plate...

I think I have pics of the bar on my build progress thread here. If not, I do have the car back now and can show you the bar anytime after work...

User 41221

Yes, you can retain the factory belts for street driving with the Redline rollbar. For a street car that gets DE'd, I think its a very functional, well though out design.

Cole

I think what we need is pictures (not just from you) of locations and dimensions of mounting points that are safe.

Something that people can take to a local builder and have a cage done.

Specs of proper tube size and thickness, Continuous overhead loop, etc.

Not everyone has a local 944 cage specialist like we do Josh.

ninefiveone

Actually, that's not the way the redline bar is mounted. It's mounted at seatbelt mounts at all 4 points. The upper mounts are the shoulder mount for seatbelts.

docwyte

I'll take some pics of the my rollbar when I get home tonight. Mine is 1.75" DOM, 1 piece for the main hoop, 1 piece diagonal and seperate harness bar that bow out to accomadate taller drivers.

ausgeflippt951

Sorry for the confusion; my comment was meant as an aside, not as an explanation. Tensile strength is a material property, meaning that it is independent of the dimensions and relative size of the part. It's measured in psi (or Pa), meaning it's a force per unit area. It's just a way of comparing two dissimilar materials, irrespective of the part sizes. Sorry again; engineering jargon.

I completely agree with you that the cage will be "stronger" (i.e., able to withstand a higher load) than the bolt will. However, I was merely pointing out that the bolt should NOT be a failure mode (given that it has superior mechanical props to those of the cage).

That said, the bolts won't be a failure mode only as long as they are properly sized. Based off of the points where the Redline bar mounts, it's perfectly acceptable as a harness bar, but I would definitely NOT rely on it as a roll bar (or to aid stiffening the chassis). Heck, I would be leery about the Autopower setup as well....


Again, didn't mean to alarm.

Chris White

Yes, all true – but the typical failure is not the bolt breaking but the material that is has been bolted into failing. In the case of a typical ‘bolt in’ roll bar the bolts are going into sheetmeal with a backing plate. You will rip up the sheetmetal long before the bolts fail.

The Redline harness bar (its not sold as a rollbar!) is not bolted into a lift hatch mount – it is bolted into four factory seat belt mounting points – which are well reinforced. Even though the Redline harness bar is not marketed as a roll bar I believe that the mounting points are stronger than unreinforced sheetmetal and the strength of a mounting point in shear is a preferred way to go.

What I really believe is if you think you need a roll bar what you really need is a welded in roll cage. A roll bar will not provide much help in a rollover at the track. This I have seen in person.

Fluidplay

mmm...you guys are all making really good arguments on your points, but not hitting the mark on my original question. So I'll rephrase it.

If you had to choose between Redline or Autopower, which would you choose? Again, this is primarily a street car used for 6-8 AX and 2-3 track events per year.

If I ever turn the car into a track machine, I would certainly have a complete gage fab'd up & installed.

docwyte

As I said in my original post, I wouldn't chose either. Save up until you can afford a properly designed, welded rollbar.

2bridges

autopower without a doubt

Bri Bro

Redline for a bolt in bar. It attaches to four reinforced mounts with hardened bolts. If you are into welding and adding reinforcement plates, the options open up.

Fluidplay

Classic

User 41221

I thought I was pretty clear in my preference. Redline, it works well and you won't be sorry.

Chris White

Ok, how about another ‘answer’

If you are seeking a good harness car then the Redline part is one of the best harness bars you can get.
If you are seeking good crash protection then the Autopower is very minimal in added protection.
If you are worried about protection you should have a Hans device way up on your safety budget. You are much more likely to die of a head and neck injury that a roof collapse in a roll over…

If I were in your shoes I would get the Redline bar, a good seat and harness system and the Hans device. And I would drive remembering that I don’t have a cage….