Car classification.

Questions, comments, and discussions concerning COMSCC rules.

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dennis

Post by dennis » Tue Apr 25, 2006 5:39 pm

DanB wrote:Also, as mentioned above, you only need a roll BAR, not a full cage.
I was debating roll bar or cage, but I think if I'm going to be putting one in, I should put the whole cage in, it was only $70 more for the whole cage and 100 more for the install, so I figured that I should just get it out of the way.

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Post by DanDarcy » Tue Apr 25, 2006 8:06 pm

That roll cage is made by Compition Engineering for drag racing. and is a loose bunch of tubes that have to be fitted and welded together. I put one in my car but it cost $700. to install not including prime and paint. I doubt if anybody will install it for $100- . Check the price before you commit to installation .
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Post by offcamber09 » Tue Apr 25, 2006 10:18 pm

DanDarcy wrote:That roll cage is made by Compition Engineering for drag racing. and is a loose bunch of tubes that have to be fitted and welded together. I put one in my car but it cost $700. to install not including prime and paint. I doubt if anybody will install it for $100- . Check the price before you commit to installation .
I bought the C.E. kit for my last Mustang and fabbed it myself- 12+ hours later I had the thing held together with duct tape and brought to the welder. I think he charged me $150 for the welding. The "pre-notched" tubes are not nearly notched enough. Lots of grinding. The price is right though as the price of steel is crazy high now.
Good luck- I like your enthusiasm !
Scott Rosnick
#09 BMW 318ti-6

dennis

Post by dennis » Wed Apr 26, 2006 9:41 am

DanDarcy wrote:That roll cage is made by Compition Engineering for drag racing. and is a loose bunch of tubes that have to be fitted and welded together. I put one in my car but it cost $700. to install not including prime and paint. I doubt if anybody will install it for $100- . Check the price before you commit to installation .
I meant $100 more than if he was just doing the roll bar not $100 for the whole job

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Post by BrakeL8r » Wed Apr 26, 2006 9:59 am

dennis wrote:I just placed order for a 10 point weld on cage, 5point harness and a new driver seat, and full suit.
Dennis: keep in mind you will need the same harness for the passenger (since you will need an instructor until you get signed off).

Also (very important):

All roll cages/bars must be padded with non-resilient material
such as Ethafoam or Ensolite with a minimum thickness of 1/2"
in all areas which may come in contact with the driver's
and/or instructor's helmet. Similar padding is recommended in
areas where the driver's and/or instructor's arms or legs may
come in contact with the roll cage/bar.


--Michael
ST4 Miata #176

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Post by WillM » Wed Apr 26, 2006 10:56 am

Hi Dennis,

Welcome to the club!

I applaud your efforts for getting a rollcage! Safety has to be a priority, and I would suggest that everyone build their cars as if they were going to be rolling over in them, especially high-hp cars and those classed SP and higher. Often it seems that safety features take a back seat to performance upgrades. I know I was guilty of this with my first COM car, which was my daily driver. The first time I came around NHIS turn 9 a little loose (at my first event), two thoughts immediately came to mind:

A. I won't be very happy if I wrinkle a fender on this car, or worse.
B. I really don't want to be barrel rolling in this car with only a rollbar.

Not only were these two points true, but they were also a distraction from the task at hand. Those of us that have been around for a while know that things can go wrong very quickly and sometimes unexpectedly. Ask the guy (I won't mention any names) who had clear track in front of him, came into the braking zone of 3, learned the hardway that the car infront of him had dumped its coolant, cartwheeled his NSX along the tirebarrier, which then came loose and landed dead center across the top of the car. Ouch! Next time I saw him at an event he was in a Miata with a full rollcage.

I bought a relatively inexpensive dedicated track car the following year. The first thing I installed was a taller, beefier rollbar with doorbar extensions. Shocks & other upgrades were done throughout that season. Immediately after that season, I replaced the rollbar with a customized full weld-in cage. I had the work done by one of the local reputable guys (Chris Howard).

My next car will have a welded in rollcage installed before anything else. In fact, at that point the cage and chassis will be considered one unit, and the car will be built around that foundation.

I guess what prompts my post is the prices listed for your cage. While it is definitely a step in the right direction, $250 sounds unreasonably inexpensive for a cage. I think cost of materials should be that much alone. The whole cage will only be a strong as its weakest link. Yeah, that is a cliche, but it is also true. We are lucky to have several well known cage builders around in this area. I would go visit a few, talk about what your expectations are, and figure out the right path. These are guys with experience that know how to design and build SAFE cages. It seems we often spend big bucks on going to the 'right' engine builder or the 'hot' suspension setup, then go with an affordible option for the cage.

Best of luck with the build, and I hope everything comes together well. It is really great to see new members come in with a bunch of excitement and bring a breath of fresh air into the club!

Cheers,

Will
96 Miata #72 SC
PRA 4 :sunny:

dennis

Post by dennis » Wed Apr 26, 2006 12:39 pm

awesome!

Just added another 5 point harness to the order.

I wasn't aware of the padding. I'll order that up as well.

I hope I don't end up dipping too much into next year's funds.

Thank you!
BrakeL8r wrote:
dennis wrote:I just placed order for a 10 point weld on cage, 5point harness and a new driver seat, and full suit.
Dennis: keep in mind you will need the same harness for the passenger (since you will need an instructor until you get signed off).

Also (very important):

All roll cages/bars must be padded with non-resilient material
such as Ethafoam or Ensolite with a minimum thickness of 1/2"
in all areas which may come in contact with the driver's
and/or instructor's helmet. Similar padding is recommended in
areas where the driver's and/or instructor's arms or legs may
come in contact with the roll cage/bar.


--Michael
ST4 Miata #176

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Post by therooster » Wed Apr 26, 2006 6:21 pm

I don't want to rain on your parade, but I would check to see what material that cage is made of. The web site only state what size the tubing is. The COM rules state no "ERW" tubing for a car of your weight. I am positive that you could probably get away with using it and no one would notice, but the rule was written (adapted from the SCCA which I do not think allows any ERW tubing anymore) due to the relative stregnth of the material. Just a thought.

Chris A.

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Post by dinoracer » Wed Apr 26, 2006 8:24 pm

I'll second Chris on the roll bar tubing material.

DOM tubing, which is required now by most organizations and will be by COM, costs about twice as much. I used a 10 point kit DOM tubing, from S & W racecars, the kit was about $ 600 delivered, then I bought another 20 feet for future door bars to be added next winter.

The padding can be ordered from nay of the many race parts suppliers.

Good Luck!
Tom Cannon

Former COM Chief Steward (fka Chief of Operations, Chief of Tech, assistant BBQ cook, Club Secretary....I been around a while)
#26 - 2000 Black Miata (sold) - co-driver of the orange 318ti .. thanks Scott!

dennis

Post by dennis » Wed Apr 26, 2006 9:42 pm

It says 1-5/8" x .134" wall EWS tubing.

EWS tubing starts its life as a standard flat sheet, and is rolled and electrically welded at the seams to make a tube.

DOM does not appear to be a type of tube but rather a bending process. (Drwan over Mandrel). Thus waht they call a DOM tube is either a ERW or EWS tube that's gone through a Mandrel bender.

the cage I'm getting is EWS tube but will be cold mandrel bent. I am not sure if this is what the refer to DOM tube.

They are to bend the pipes on Monday so if I've been misinformed please let me know so I can make appropriate adjustements.

thanks

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Post by SSNH » Thu Apr 27, 2006 6:54 am


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Post by cfossum » Thu Apr 27, 2006 7:07 am

Dennis,
I think you are mostly right. Here is what I know.
ERW tubing starts out flat and is rolled into a tube, like you said, except I'm not sure what EWS means. ERW is Electric Resistance Welded.
DOM takes the same ERW tube and takes it a step further. But instead of being mandrel bent like you said, its more like they mandrel straighten it. This added process produces more uniform wall thicknesses, and more importantly, since the material was cold worked even more, it becomes harder.
The trend has beed to phase out the use of ERW and EWS for use in roll cages, and more organizations are specifying DOM. Fabricators like to work with ERW better because it is easier to form.
Good luck with the cage. Its a big deal, but worth it if you ever end up needing it.
-Carl

dennis

Post by dennis » Thu Apr 27, 2006 12:30 pm

Thank you for the clarification.

So is EWS and ERW process the same?

EWS = electrically welded seams.

MRLM3

Post by MRLM3 » Thu Apr 27, 2006 1:57 pm

Dennis,
I believe EWS is the same as ERW. DOM tubing as stated is ERW tubing that is cold drawn, eliminating the flashing from the welding and virtually eliminating the seam. Much stronger and pretty much the standard for cages. BMW club racing is eliminating ERW as of 1/1/07 and I think SCCA is going the same route. Just from the costs that you are quoting, sounds like you're looking at ERW.

dennis

Post by dennis » Thu Apr 27, 2006 3:37 pm

Thank you guys for the heads up on this.

I managed to get the order changed to DOM tube.

$450 was the price for 10 point cage for DOM.

Thank you guys again. You guys saved me a lot of trouble and hastle of having to do the cage again next year.

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