Anybody have a half cage installed or seen one installed in an RX-8? I'm not talking about a bolt in like the Autopower, ect. I'm talking about a custom job welded in and not mounted to the wheel well and floorpan.

If so, post pics!

These aren't from an RX-8 but I'm looking for something like this:

 

Guess not...Anyway I'm looking into it.

 

You're asking a question that I don't think many guys have treaded on yet. In the Miata community, you see a ton of cages (good ones and bad ones) since they have racing series that require it - like Spec Miata.

Do guys have cages? Yes.

Does the average track day use justify a cage? No. Does it justify a half cage? No.

Unless you're like Speedsource or running a series that requires it. I wouldn't see the need for adding weight of extra DOM tubing in your car. It does help with stiffening the chassis, but it's definitely overkill for the stock power levels and track speeds.

 

The one thing to keep in mind with even a half cage is driving the car on the street like that. The primary danger being that you won't have a helmet on while driving on the street which could prove fatal if you managed to smack your head on the cage.

Granted, if it's a half cage (4 point?) it would be in the back seat and if you ended up back there in an accident you did something really wrong.

Then the issue of whether or not a half cage is even worth it comes into play.

I think even average track time would warrant a roll cage to be honest but it's not a requirement. Safety is of primary importance on the track and a cage would seriously increase your chances of surviving a bad crash. The problem with having it in a street car is your safety off the track.

 

I know all of that stuff. This is a street car that I want to install a rollbar in.

Here is where I am coming from:

I'm in the camp that says don't run seats and a 5 or 6 point harness in a car without a rollbar. The reason I say half cage instead of roll bar in this thread is that the only rollbar I have seen for the RX-8 is a bolt in from Autopower and I do not like the way it mounts.

Here is what I am talking about. Apologies to the original poster of these pics. Look how the bar mounts. It mounts to the thin metal floorpan of the car and the thin metal in the wheel well. I don't trust those mounting points in an actual accident.

 

The rear bars could have gone more towards the top of the wheel well. If you really worried than you can weld some 1/4 steel plates 3x the size of the pad of the rollbar so it has more surface area. So now instead of pushing your finger through a piece of plastic your trying to push your fist.

I think most of us with roll bars are all autopower bolt in. Eric Myers might be the only other one with a true welded in cage.

Just another note be ready to pay big money for what your looking at. A good shop will charge you 2-3k. There isnt much room to crawl in behind the seats to do lot of welding. Time is money my friend.

 

trouble is---where would you wield it too?
OD

 

I got a good look at a cage in a "real" RX-8 race car this weekend designed by a team I have a lot of respect for. The design in the rear was much different than I had imagined. It can be done but it will involve removing a lot of the interior to do it right. Really after looking at that setup I can't see doing it without going all of the way and putting in a full cage. Looks like I may be headed down the road of full out race car. May not even be an 8.

 

Are you talking about the plates so you have more surface area? Very easy. Under the car and inside the wheel well.

I removed my rear seats for my bar. Theres pictures in the calling all interior thread. Im trying to finish a brace to clean up the inside a bit more but hard to find time with so much OT I work.

 

I apologize as the half cage pictures the OP posted in the first post I couldn't see due to me posting at work! A cage design like that in the RX8 looks like it would be much more functional than the other ones I have seen.

 

I took a look at your setup and it looks very nice.

The design I saw uses the area where you have your rear strut brace mounted. I see you have already removed the black plastic divider behind the back seats. You'd also have to remove the factory cross braces as well as the rear decklid pieces. The headliner and the interior trim where the airbags are in the rear would also have to go. In addition some reinforcing of the floorpan would need to take place and the carpet would probably have to go. To weld it all in you would probably need to remove the rear glass as well.

It's a big job and 2 - 3k is probably not far off price wise although you could do all of the interior removal yourself and save some money.

 

Thats just the fab work. Want someone to weld you something, its $125 just to turn on the welder before you start talking

 

Half cocked would be a better description. There's a reason real racing organizations require a full cage with padding and a helmet.



.

 

It can be done and done safely. A decent space between the bar (not cage) and your head is the key. Check here for some cage pics of a car we did last year or so. http://s254.photobucket.com/albums/h...ng/RX8%20cage/
The RX8 lends itself well to installation of a half cage. I would say cost wise in the neighborhood of $800-$900

 

A little shout out to Mr. Bergs cage shown above and in this post. I believe some of you will find this post informative. Heres the setup:

All car nuts go through the stage when they consider some type of improved safety in the form or a roll bar(s) and/or a roll cage. They often will look on the internet to see what ss available when in reality the majority of cages are custom made. Many a first timer will end up buying a kit which is only as good as the person who installs it. The majority of the other cages are typically made by import and hotrod/V-8 shops, guys that know how to weld and who have possibly have made a few for drag cars, perhaps an auto-x car, etc. A smart cage builder and/or shopper will refer to rules of a particular sanctioning body. The SCCA and NASA are excellent rule set sources to refer to for either an Auto-X, HPDE or Club racing car. Read them twice. Then read them again twice. Here is why I say this.

If your uncle leipold the welder will make your cage for a case of cheap beer, he may often make a cage on how HE thinks it should be made. If you have nothing to refer to (one or more rule sets for example) then you can end up with an incorrect cage that CAN be unsafe and MAY NOT pass a NASA or SCCA tech inspection. The main thing is the cage or rollbars may be unsafe.

Most first timers don't know what to look for in a cage. John Berg has been kind enough to provide a great shot of one of his cars that we can use to point out a few things.

Provided in the picture below are several red arrows. The purpose of these arrows are to show a new person ONE of the things you'll want to look for. Notice how several of the bars connect and/or terminate in the same location. This is one of the primary things to look for in a cage design. Another is the use of triangulaton. Notice the use of the triangle shape. How many triangles can you find in the picture? Several. You'll also see several reinforcement tabs and gussets. Some of these are drilled out to reduce weight.

Look for these concepts when buying a car with rollcage/roll bar and/or designing a safety solution. One of the best things you can do is to attend a Grand-Am or World Challenge event. DON'T just look at the SpeedSource 3 rotor GT cars and ohh and ahh. These are very different cars (as most GT cars are). Neither should you look at JUST RX-8's with cages. Look at cars like BMW, Honda, Porsche, VW..... They all have benefits and unique ideas you may want to incorporate into your build. If attending one of these events feel free to contact a crew member and take several pictures of the interior of various cars. This IS allowed and often all you have to do is ask a crew member and they would be glad to help.

Hope this has been helpful. Thanks to John for the pic.

 

Gee thanks Eric, I'm flattered
BTW check this out

 

Thanks for the posts and the pics. The more cages I see the more I can tell what's different about them. I'm also getting a much better idea about what it is I really want. There is more than one way to skin a cat!

 

Here is one of our new RX-8 projects. Another thing you'll want to look for are connections of the tubing to the car body. This is sometimes seen with the A pillar tubing connected to the A pillars. For those of you who don't know what this is: The vertical windshield braces on the side of the windshield. Sometimes you'll see these with 2 or 3" holes. Often these are large reinforced gussets. Their purpose is to tie these areas together for added rigidity.

 

^^I like this one.

John's design does allow for keeping more of your interior though if that is your goal. To be honest though interior pieces are starting more and more to look like weight to me.

$800 - $900 is a good price for something you can be pretty sure is going to do it's job when the time comes. 1000% better than the Autopower at about twice the price.

 

I would budget for AT LEAST $2K. AT LEAST. A quality tubing notch effort with several small triangulated support bars is what you want. Seamed welding will cost extra.

To save dollars you will naturally want to remove ALL the interior including the dash panel. Be smart and remove all wiring---the RX-8's don't like a gutted or fiddled with wiring harness. Ask me how I know this. One of my mechanics is an electrician and for our first builds we removed approx. 30 lbs of wire out of the wiring harness. We did this twice. Both times we took much precaution on this effort. Both times we had reoccuring headaches due to wiring. This is one reason we went to a total stand alone system.

Back on track----You will want to gut the car which includes removing (and keeping) the front and rear glass. Gut the doors yourselves. Most fabricators will accept a rolling chassis so that is your objective---a well gutted rolling chassis.

Seam sealer. This is the stuff that looks like it was put on with a 4" wide paint brush. Seam sealer is the enemy of cage fabricators. They will remove it for you but it will cost you. You need solid metal to weld to in various places where the cage will attach to the uni-body. Grind these down yourself.

Now the tough part. Are you ready for this Spring and HPDE'ing or Time Trialing? Well your too late. Everybody and their friggin' brother is now just asking to have something built. If you're one of these people you've missed the boat. It has sailed. Wait for the next one. Smart drivers (and I'm offering this so you guys can plan ahead) start their projects in October. October is when fabricators are looking for work and willing to deal with you much better than March (when everyone decides to build a flippin' car at the last minute). Generally speaking you can get waaay ahead of the game and have your new car back before christmas. This allows you to complete it and sort if out BEFORE your racing or TT points season begins.

There you go everybody.

Happy rotoring.

 

I would budget for AT LEAST $2K. AT LEAST. A quality tubing notch effort with several small triangulated support bars is what you want. Seam welding will cost you extra.

To save dollars you will naturally want to remove ALL the interior including the dash. Be smart and remove all wiring---the RX-8's don't like a gutted or fiddled with wiring harness. Ask me how I know this. One of my mechanics is an electrician and for our first builds we removed approx. 30 lbs of wire out of the wiring harness. We did this twice. Both times we took much precaution on this effort. Both times we had reoccuring headaches due to wiring. This is one reason we went to a total stand alone system. Remove the steering rack, pedals, doors, hood, trunk, etc....

Back on track----You will want to gut the car which includes removing (and keeping) the front and rear glass. Gut the doors yourselves. Most fabricators will accept a rolling chassis so that is your objective---a well gutted rolling chassis.

Seam sealer. This is the stuff that looks like it was put on with a 4" wide paint brush. Seam sealer is the enemy of cage fabricators. They will remove it for you but it will cost you an arm and a leg. You'll want to do this yourself. You'll need solid metal to weld to in various places where the cage will attach to the uni-body. Grind these down yourself.

Now the tough part. Are you ready for this Spring and HPDE'ing, Racing or Time Trialing? Well your too late. Everybody and their friggin' brother is now just asking to have something built. If you're one of these people you've missed the boat. It has sailed. Wait for the next one. Smart drivers (and I'm offering this so you guys can plan ahead) start their projects in October. October is when fabricators are looking for work and willing to deal with you much better than March (when everyone decides to build a flippin' car at the last minute). Generally speaking you can get waaay ahead of the game and have your new car back before christmas. This allows you to complete it and sort if out BEFORE your racing or TT points season begins.

There you go everybody.

Happy rotoring.

 

eric meyer throwin down knowledge.

nice pics berg.

i have to say these forums are very helpful.

 

In my racecar, I had $1200 into an Autopower cage (1985 dollars). I can't and don't know about welding, so had it welded by a shop that was a "professional" cage shop. I got to an SCCA race and the tech inspectors found a bad weld done by the "professional". I was refused entry into the race that day. I later had the welds ground down and redone by another shop.
Another local shop took deposits for building cages and never delivered. I fortunately didn't get to the point where
What's my point? Check out the shop that is building your cage throughly.

 

Here is a half cage in a Mustang I did a couple of months ago. All TIG welded and most of the interior went back in. Car is mostly used as a track toy but he still drives it on the street.

 

Isn't it sad that this is the typical experience of a customer that wants to introduce more safety into his/her passion. Buyer beware everyone.

Here is a reference: John Weisberg (Berg) in this thread is someone who I would do business with. Good guy. High quality work. The first RX-8 I ever purchased already had a cage in it----John put it in.