Can I use a C5's factory roll hoop as the main hoop in cage?

[Cobra4B]

I'm tall so space is important to me in my track cars. I will be caging my Z06 this winter for PTA/ST2 competition and want to preserve as much interior space and sightline as possible. C5 (and C6s, maybe C4s, but I don't know those that well) Corvettes have a factory rollbar as part of the frame. Using it as the main hoop for a cage would make a C5 cage intsall much much cleaner/better. Could this be done and pass race tech? If not why not?

 

Here's a C5 with all body panels removed, you can see the factory "rollbar".... the C5's body panels aren't structural so this part is the roof structure.

 

 

Here's a recently completed cage on a 2004 Z06.. you can see how the main hoop is below the factory hoop and must come in front of the rear bulkhead to get down to the frame rails properly. This is how I've seen every C5/C6 cage install done and it reduces seat room and viewing room.... most of the time I can't see out the back of a caged C5.

 

 

I have seen some builders like DRM who are making World Challenge type cars cut the bar out, take the whole roof off, then re-make the main hoop in the place the factory one was, but to do that you have to run a composite aftermarket roof and use lexan front/rear and no side glass. I don't wish to do that. Here's a pic of that type fo setup...

 

 

-Brian

[getfast]

Corvettes have a factory rollbar as part of the frame. Using it as the main hoop for a cage would make a C5 cage intsall much much cleaner/better. Could this be done and pass race tech? If not why not?

 

Presumably because it doesn't meet the type/size/thickness of tubing required by the CCR.

 

Wouldn't leaving it in and building a normal main hoop beneath it theoretically provide more structure/protection anyway?

[kbrew8991]

doubtful, unless there is some sort of FIA certification of the C5 chassis.

 

I'd ping someone at the National office for a final ruling though. Hope that helps!

[Cobra4B]

John my issue is my height and rearward visibility... plus putting in a main hoop that has to come forward of the rear bulkhead limits how far back you can put the seat. Just thinkig of ways to maximize interior space for myself. The right way to do it looks to be to take the roof off and replace the factory hoop w/ the rollbar and then put the roof back on... it's more work but doable.

 

Looks like the main hoop is on the thin side vs. required rollbar tubing....

 

[getfast]

 

That would violate several rules in the CCR... for instance 15.6.5 "None of the tubing may show any signs of crimping or wall failure. All bends must be Mandrel type."; 15.6.6 "One continuous length of roll bar tubing shall be used as the main hoop."; 15.6.13 "The roll cage shall be mounted to the floor area of the car in six, seven, or eight points."

[Cobra4B]

I'll probably just end up pulling the roof for the cage install.

[jimbow]

I'll probably just end up pulling the roof for the cage install.

 

That will be the right way - I'm faced with a similar issue with my 92.

Its one of the main reasons I'm sticking with time trials for now.

[sperkins]

I'll probably just end up pulling the roof for the cage install.

 

That's a crap load of work for little gain if any IMO. The right cage builder can do it for you where you'll have good visibility. I'm nearly 6'1 and can see perfectly in mine. Lowering your seat will make a big difference as well. Lastly, you can drop your mirror slightly if needed.

[Cobra4B]

Its really not that much work to get the roof off... just some bolts and adhesive.