Center Net Mounting

#1

NASA is requiring a side impact head restraint (aka center net for those without seat head bolsters) for 2007. How are people mounting them? I’ve honestly never seen one mounted that I can remember. Especially not in an E30… Pics would obviously be quite helpful if possible. Thanks,

#2

There’s a pic in the BMW CCA CR Rules. Scroll down to page 20.

Basically, I think it loops around the cage behind the seat and connects to a tab on the dash bar (or front bulkhead). There should be some type of quick release up front (the red handle) so you can get out the passenger side if need be.

#3

What have you installed to comply with this rule?

I can only find these offered by Simpson or Race-Tech.

Are they any others?

-Scott

#4

Appex and HMS both have them.

http://www.apexperformance.net/cartgenie/prodList.asp?scat=345

http://www.hmsmotorsport.com/store/track-safety/win-nets/cage-nets

#5

Is it just me or does anyone else think that the length of the net will allow a fair amount of stretch, in a major right-side hit?

I’m tightly belted into the seat so my body won’t go anywhere and my head doesn’t have to go very far to cause a serious injury. It seems like this center net will let the driver’s head move a lot…unless it’s extremely tight (and/or right against the right side of the helmet), which I don’t think will be the case in most mounts.

I know my HANS won’t help much in a right side hit but it looks like a strong and padded tubular bar type helmet surround is the only thing that will keep a driver’s head upright. Has anyone considered welding something like this to the main hoop. Of course, it wouldn’t work with an adjustable seat but for a fixed seat, it would certainly be more effective than a long net.

Carter

#6

Carter,
I think that might be easier (and maybe even safer?) to buy seat with side head protection (you know those "wings" on top of the seat…). Instead of paraphrasing here is the snippet from the email I got from Joe Marko from HMS motorsport. Since this is safety related question I hope Joe doesn’t mind contents of email being shared (actually I snipped some stuff and this part has been posted by Joe on some other board…). He did email me some pics of install so if anyone wants them email me and I’ll send them to you.

Igor

[quote]
The interior net is best used in conjunction with
a seat having the side head supports. In a 30 mph/28g
45 degree impact, your back would be approximately 6
to 9" off the seat back and probably beyond the head
rest.

Often angular impacts are immediately followed by a
side impact. If with the belt stretch you are the 6+
inches forward there is a good possibility you could
get caught on the outside of the headrest on the
rebound phase or at a minimum have a neck extension to
the side.

The interior net solves both of these problems and
also serves to provide additional support to the seat
back and head rest. The interior nets with 3 or 4
straps seem to work the best for most sedans. The
lower strap(s) should be wrapped around the seat at
about 6" below the shoulder height back to the
"b-pillar" main hoop. The uppermost belt should be
mounted so that the top of the net is just below your
line of site and above the shifter at the front.[/quote]

#7

Carter wrote:

[quote] Has anyone considered welding something like this to the main hoop. Of course, it wouldn’t work with an adjustable seat but for a fixed seat, it would certainly be more effective than a long net.

Carter[/quote]

Since the seat isn’t attached to the cage, I don’t think you want a part of the cage in that close proximity to your head. Only an issue in a very extreme crash…
cheers,
bruce

#8

I’ve been meaning to post pictures of my set-up for a week (although it’s obviously not tightened up in these photos). I have an eye bolt welded to a plate on the front bulkhead that pokes up through the dash. The net is from Safety Solutions, and it’s pretty snazzy.

Sasha

#9

Here’s the net. [file name=DSC05353.jpg size=125559]http://spece30.com/media/kunena/attachments/legacy/files/DSC05353.jpg[/file]

#10

For the lazy:

JP

#11

Will a center net be required to pass tech???

#12

In June it will be required. It is June right?

#13

July 1

#14

it is either the center net or a seat with the head bolsters.
bruce

#15

Sasha, I like what you’ve done… unfortunately, my aux gauges are right in the path of the strap… :angry:

Anyone know of any deals on a Cobra Evolution GT/Sparco Circuit Pro/Recaro HANS SPG?

Better yet, anyone want to give me some cash for a nice Recaro Pole Position with 2 years left on the FIA cert and aluminum side plates…?

#16

You might check with Walter at Valley Motorwerks - he’s on this board a lot too. He is a distributor for Racetech which have seats with the head support. I had a Sparco Evo2 and thought about the net but just bit the bullet and got the seat as I’m trying to go top shelf on safety whereever possible. I’m sure the Sparco is a great seat too, and I asked around about Kirkey (here and others), and seemed most feedback was to not go aluminum. Sure see a lot of them around though.

#17

Sasha, thanks for the pics. That was very helpful.

Does anyone know if instead of welding an eyebolt into the dash bar, if it would be ok to just drill a hole through it? Or does that severely weaken the dash bar’s integrity?

#18

I don’t think you need/want to do either. I’m still waiting to see an actual center net in person, but if you have a crash bar under the dash, all the photos show a harness-style buckle for the forward end, so you should be able to just wrap it around like a shoulder harness and cinch it down.

For those who don’t have a crash bar, in the 2007 BMW CCA (I know this is NASA but the NASA regs don’t specify a mounting approach) a suggested alternative is to attach a metal cable to a reinforced mounting plate drilled through the firewall. That seems like the best option for those w/o the crash bar.

Another option for some folks could be to use something like the mounting bracket for the Longacre mirrors and bolt that around the crash bar and attach to it. I’m not sure that it’s a strong enough piece, though, so that’s a question.

#19

Excuse my ignorance again, bur I thought you couldn’t cut the dash, except for the front down tube.
I don’t want to be a pain, but that car with the hole in the dash is not built according to that rule (7.4.3.)
If I’m wrong, I apologize, and would like an explenation to that rule, and if that it’s an acceptable exeption that tech inspectors would overlook since it’s a safety issue.

#20

For anyone thinking about this issue you might want to check out the video on the HMS Motorsports website. It will give you a new appreciation for what kind of head, neck and body movement is possible with a side impact. It seems to me that anything you can do to restrain lateral movement would be worthwhile.