FYI: Door foam

[ekim952522000]

I am sure allot of you guys don't go on Honda-Tech so I wanted to post these pictures where a guy used IMPAXX foam from the NASCAR car of tomorrow on his car.

You can read on this stuff here this is where he got it from.
http://www.rollbarpadding.com/prod_impaxx.html

If this stuff is affordable and readily available this would definitely change how I decide to do door bars in my next car.

Just a FYI for people in case you did not know this stuff was out there.

If this stuff is affordable I would probably do a nascar door bar design shallower than typical with this stuff between the door and the cage on my next car.

[GBugg]

Having recently slapped a wall (hard) at Road ATL with the driver's side of my CRX, I am looking into this for sure. My impact was nearly 100% lateral - didn't even crack the headlight - and hard enough to buckle the chassis side to side. There was NO energy absorbed in the door. I'm not sure how much the foam would have helped, but anything would have been better than what I had.

[Andy Bettencourt]

Greg Amy might be able to illustrate this better in words but after a couple of bad crashed in '08 here in NE, I want any and all 'protection' as far away from my person as possible.

[pballance]

Interesting. I have thought about using the foam as a filler to the door since my current cage does not intrude into the cavity.

I know this will probably open a can of worms. Current rules do not allow "gutting" of the door cavity unless the cage intrudes. I know it is a slippery slope, but, I wonder if it would be permitted to gut the door to install the foam without extending the cage into the cavity and use the foam for an "intrusion"?

Also, I haven't searched but what are(is) the fire rating of the foam?

Just thinking out loud off of the top of my head. I will wake up later today and see the errors of my thinking but what if?

[Greg Amy]

Basically, you want door protection that's strong enough to push your car out of the way when you're hit in the side (so it doesn't intrude into you). But, when the severity of the crash is such that the structure will collapse, you want it far enough away from you so that it can absorb most of the energy as it collapses, before it gets to you.

The use of side impact foams (and other similar collapsible structures) takes a different tack than the above. The purpose of these structures is to collapse and absorb energy as it does so, such that the energy is dissipated when it gets to you.

I'm not confident that any of us have the tools and technologies to design these correctly, especially not within the existing Improved Touring rules. This technology is a bit more complex that just cutting-to-fit the available space... - GA

[tnord]

I know this will probably open a can of worms. Current rules do not allow "gutting" of the door cavity unless the cage intrudes. I know it is a slippery slope, but, I wonder if it would be permitted to gut the door to install the foam without extending the cage into the cavity and use the foam for an "intrusion"?

if it were me, and i'm working on the miata, i'd take the vinyl door panel off and stuff the foam between the door skin and the structure of the door. not sure if other vehicles would allow something similar, but in the end i'd want to find a way to put the foam between the door skin and the door bars of the cage to absorb the initial impact.

[pballance]

That is what I was thinking Travis. But, as Greg reminded us there is a lot more to just filling the cavity.

Just thinking out loud but wouldn't simply putting the foam between the door skin and cage allow for the foam to load the cage door bars over a wider area? Again, I am not an engineer and this may require a re-design of the cage bars to accept an altered impact area.......

makes my head hurt...

[lateapex911]

I'm not confident that any of us have the tools and technologies to design these correctly, especially not within the existing Improved Touring rules. This technology is a bit more complex that just cutting-to-fit the available space... - GA

Oh, absolutely!

But...many cars out there are using door bars that might intrude into the door cavity, but are far from the actual door skin/door beam. In cases like that, I think adding a crush structure like that (foam) can't hurt. It would help slow the impact the door bars see, reducing the g loads on the occupant, and also the overall damage to the cage structure.

[rsportvolvo]

I can't seem to locate the FIA spec for impact absorbing structures, but I stumbled across this interested article on the side impact foam for FIA WRC cars:

http://www.fiainstitute.com/news/news_280109.php

[raceita]

Possible problem with foam. Upon impact the foam might pass by side (door) bars of the cage and intrude upon the drivers’ position. I.e. it would reduce the effectiveness of the side bars by allowing some of the impact energy to bypass the cage.

It needs something to dissipate energy to. From all possible angles of impact.

[chuck baader]

First, if you look at the NASCAR mounting, there is a plate welded to the door bars to support the foam. AND THE FOAM IS BETWEEN THE DOOR AND THE BARS, otherwise, it does no good (Honda guys are different, I guess). Any energy adsorbing material we can get between ourselves and a solid object is beneficial. I would not hesitate to add this to my cage had I enough room between the door bars and door skin. IMHO...Chuck

[Tristan Smith]

Is it legal to use this stuff? Don't believe it says we can use this in the rules, and it certainly would be straining the rules to call it roll bar padding.

[joeg]

looks like padding to me!

[ekim952522000]

looks like padding to me!

X2

[Tristan Smith]

Roll bar padding on the outside of the bar? Away from the driver? And if that were to fly, what about the GCR rules about "performing no other function". Clearly absorbing energy in a crash is different from padding a rollcage from driver injury.


Look I am not necessarily against the concept. I am all for safety. But I do find it interesting that people in these forums argue continously about the legality of certain things down to the minutae, and yet that issue hasn't even raised it's head here.

And I am not even a rule nerd.

[joeg]

But there is no definition of "padding" in the GCR.

[Flyinglizard]

I use the foam in the side of the ministock, between the inner and outer skins. It loads the whole door a lot better than just the door bar.
The expanding foam, filling up the bottom 4 in or so, along with a sheet of 1 in foam(blue or pink), set flat inside the door, glued to the expanding foam would be ideal. The side loads are sheared through the flat foam, using the whole door as an absorber.
This will only help if the foam has a flat area to impact. Door panel, side cage plates or something like it.Removing the "push panel" will negate most, but not all of the foam's crush value. Pushing the foam into the driver will not harm said driver in any way,other than maybe covering him in some pieces of foam..
Foam burns in a bad way... SCCA puts fire ahead of impact , most of the time.
Real world, impact is a lot more often that fire issues. Most fires are out very fast, or the driver is out very fast. Most impacts,especially in our small cars, have a lot more potential for injury. Fires suck though, for sure.
IMHO.MM

[rsportvolvo]

I finally located the FIA information on their door impact absorbing structure for Production based race cars. It is located in the Super 2000 regulations.

http://argent.fia.com/web/fia-public.nsf/D1979BA97EBFED08C12574FF005313DD/$FILE/263%20(2009)-15112008.pdf

The drawing, FIA 255-14, is located on page 4.

I hope folks aren't so petty as to protest a safety item that is not mentioned in the ITCS. Howabout something more constructive like getting a spec included in the GCR to cover side impact absorbing structures? I'm a fan of adopting the FIA 255-14 spec.