mikymu

Yes, I am finally at the point where I am fast enough requiring a roll cage. It's better to live through a crash than maimed especially this track thing is just a hobby. I like the idea of OEM roll cage since it's not permanently welded but how safe is it compare with a fully welded cage? Race approved?

OK, weld in cage wins!

http://www.youtube.com/watch?v=rI7pz5FusKA

911SLOW

Oem bold cages apart from the fact that they dont destroy the cars originality or resale value, pass very strict tests that surpass fia standards easily. And have evolved through the years following the rule changes, for example the current cage has more cross sections and roof bar etc.
IMO stick with oem.
A welded cage is part of homologation for race cars, and might be safer in some extreme cases but I wouldnt bother for a street track car.
In any case whatever you choose have it installed properly and with correct padding.

And just DONT BUY A CARBON CAGE pm for details if you like.

John

Serge944

Yes!!

There's nothing wrong with bolted connections, as long as you achieve adequate tension in the bolts so that the connection relies on the friction between the roll bar/body, and not the shear strength of the bolts.

In English, make sure you use high strength bolts and torque them well.

Asquared

My dealer told me the OEM cage wall thickness wasn't thick enough to use for racing. Any truth in that?

mikymu

Thanks for the info John. Sound like OEM roll cage is a good choice. Why not CF roll cage? Is it something not PC to chat on open forum?

lol

After your off at TH on Turn 1 a roll cage sounds really good. We are too fast now days for just a roll bar. I think suncoast sell 996 GT3 roll cage pretty cheap - around $3K ... but 997 GT3 roll cage is likely better made

Don't know the answer ...

cfjan

Would be interesting to see what you come up with.. OEM vs. something like, say, Safety Devices full-cage.. waiting for your research result! (and I'm sure a great write-up will follow when you install it!)

mikymu

Yes, a full write up on roll cage selection will take place once I have everything installed ... might even strip interior and replace OEM door with a metal door shell to save weight

cfjan

If I have a 7RS, I'd look hard into the OEM cage, especially the one that Porsche uses in its .2 RS in the 24 hrs. of N-Ring races.. it seems to be the latest version (or modified?) w/ extra door bars..

911SLOW

Mikymu all I can say in thE forum is that carbon cages won’t pass any of the tests for cages, and to give you an example that is based on actual events let’s say you roll over with the carbon cage and on the first impact the roof doesn’t collapse. If the car stops rolling you are ok if it continuous to roll you are not because the cage won’t be there no more. It has been destroyed to little pieces in the first impact doing its job once and now you are rolling without one.

And for the bolted vs. welded here is a picture from 997rs with rohlr driving.
If dmbs AND FIA accept the OEM Porsche cage with bolts i don't see why we shouldn't.
Also two abstracts from adac 24h regulations that are self explanatory.

John

911SLOW

its the current version not modified simply following the rule in my post above. The only negative is that the added supporti n the A pillar is quite close to the driver's head. In the cup cars the A pillar is pushed forward past the dash.

John

cfjan

I wonder if the cage (the photo I posted) would fit a 996...

The cage that Porsche sells for 996 and 997 seems to be different.. w/ the 997 version having a different front section (dual bar at the A-pillar area)

911SLOW

The mounting points distances match.

John

mikymu

That is one nice looking roll cage. Interestingly it does not have a knee bar going across the front post to strengthen he cage in case of a side impact. Cross knee bar is something SCCA require as far as roll cage goes

Here is one P-car without knee bar and look at how far the driver side A-pillar got pushed in with side impact. strong door bars is very important too



Here is a 964 with knee bar above the steering column

cfjan

I think the OEM cage is meant to be fitted w/o gutting the interior. Maybe if the cross bar is added, you'd have to start trimming the interior pieces.

DRG13

mikymu,

Ask FRIZ here on rennlist if the OEM roll bar works...he has some first hand experience...best described as full, full, nose-to-tail full, then a round-off....and then nailed the landing...video is still out there somewhere on youtube...scary ****

What'd you get FRIZ, cut nose, sore ribs, sore shoulders?? without OEM rollbar, belts, seats and helmet it would have been UGLY...

http://www.youtube.com/watch?v=aToLBN3BrBo