Convertible Roll Bar Requirements

[modifiede30]

I read the rules for 2012 and recently began to build up a new project car for track use - a BMW M-Roadster. I've read the rules, and it specifies that stock rollover protection isn't acceptable, but it specifically identifies a few cars but not the BMW roadsters - does COM feel these are acceptable, or just ignored them because they're not as popular?

I'm planning to replace the existing hoops with a competitive bar, but not a full cage. I just want to make sure I get something that's going to pass the sniff test when I finally get to the track and go through tech inspections.

[breakaway500]

Currently, all convertibles and open top cars require a 4 point or better braced rollbar to operate on track at a COM event. M Roadster factory hoops are not acceptable,but a 4 point aftermarket will be.Make sure you pad any areas that may hit the occupants heads.

[WillM]

I read the rules for 2012 and recently began to build up a new project car for track use - a BMW M-Roadster. I've read the rules, and it specifies that stock rollover protection isn't acceptable, but it specifically identifies a few cars but not the BMW roadsters - does COM feel these are acceptable, or just ignored them because they're not as popular?

I'm planning to replace the existing hoops with a competitive bar, but not a full cage. I just want to make sure I get something that's going to pass the sniff test when I finally get to the track and go through tech inspections.

Sounds awesome, and you have the right approach. As Mark said, the stock hoops are not acceptable, and while I don't know for sure why the M-Roadster is not listed, I suspect that most cars are not listed, and that the cars that are listed are just there as examples.

A competitive bar is all that is required for Stock (SS), Street Touring (ST), and Street Prepared (SP) classed cars. By competitive bar, I mean a rollhoop securely attached to the frame with rear diagonals extending from the top of the main hoop to a point further back (or even forward) on the chassis. Get the highest bar you can, and install the lowest seat. You need to pass the broomstick test for you and any passenger (e.g. instructor) you may have. If you have a question on a specific bar, post a picture or link to it. If you are interested in having one custom made & installed, let us know - there are some very talented and capable cage builders in the area (and on these forums). You'd be surprised how competitive (price-wise) an installed, bespoke roll bar could be (in comparison to off-the shelf pre-made bars). Besides, you get exactly the bar you want, with features you may not even now you want (or need)!

Sorry, your username is vaguely familiar, but I'm not sure who you are (and whether or not you are a student/licensed driver/instructor or new to COM (so the bit about passengers may or may not apply to you).

- Will

[modifiede30]

If you know anyone in the area that could do the job, let me know. I'm much rather give the business to the small guy over any mass-produced bars since none fit the way you want them to, and most are bolt-in (would prefer weld - in).

Send along some suggestions. The only one I've found thus far that's still in production is made by Hard Dog (http://www.bethania-garage.com/images/z3_a.jpg). Not sure of the height above helmet, but obviously it would need to be sufficient or it wouldn't work.

[nateh]

Try Chris Howard (zChris on these forums). Very competent local guy.

[WillM]

+1,000,000,000 for Chris Howard.

Contact info:

(508) 429-6717 (phone)
5drew@comcast.net (email)
zChris (username on these forums)

Chris has built a couple of cages for me, including one for a Miata that was specially designed to allow the soft top to operate. There are many, many COM & SCCA drivers/racers sporting cages & bars built by Chris.

[honda8790]

Old thread but I have a similar question.

I have just sold my RSX that I used with COM for a few years and I'm moving to a S2000. I know that I need to install a roll bar and I have actually ordered a full cage for the car. For now, I want to keep as stock as possible, that includes the seats. In order to mount the harness bar in the correct location, I need to have a race seat installed which I don't plan on doing yet.

Is is sufficient to install the roll bar with the following components for track day?
1) Main roll hoop (top is 2" above my helmet)
2) Down bars from top of roll bar to rear shock tower
3) diagonal brace from top of driver's head to lower passenger side mount location

Is it OK to leave the harness bar out for now?

[paultg]

I ran my Miata last year with a hardtop, a bolt in roll bar, and stock seats and belts.
The hardtop get you out of needing arm restraints (although they aren't a bad idea).

I'm not aware of any arm restraints that will work with a stock seat belt. So, I think you'll need a hardtop to do what you are describing. Also note, if you pull the air bag you need harnesses as well. I know in my miata I cant run harnesses with stock seats, so it's getting more and more difficult to run the car with a bar and stock belts/seats.

The only reason I ran my car as described was to keep it simple for student/instructor use. Now that I am licensed I plan to update to a proper driver seat with harnesses.

Paul G.

[honda8790]

My RSX had a roll bar, race seats and harnesses which were nice to have at the track. This setup allowed me to use my HANS too. I'm also licensed so I could get away with not touching the passenger side of the car for a little while.

That's a good point about the arm restraints, I completely forgot about those. I don't have a hardtop yet so I'll have to pick up some arm restraints before Summit Point. That does mean that I'll have to install a 5 pt. harness, which means I'll need a race seat.

Well that answers my question then. Thanks! Anyone can correct me if I'm wrong.

[Georgethefierce]

the arm restraint question is a good one, what do the SS guys run? You may be able to just run them through the belt holding you pants up.

[Chrispy]

I found this one for an OEM 3-point, not sure what it connects to.
http://store.gofastbesafe.com/merchant2 ... ode=OEM3pt

[6PAK72]

When I started out, I connected the arm restraints to a 10,000lb towing-grade twist chain link and closed it over the harness across my belly.

It passed tech every time, Lee my first instructor thought it was a great solution, and none of the subsequent instructors had an issue - probably because they were too busy praying to care