I dont know if you guys have heard of this, but when I was lookin for ways to stiffen my chassis I decided I wanted to get SFCs, but I found another way which might be even cooler to stiffen the chassis, make the car safer, and reduce noise levels. The stuff is called structual foam. It seems like an amazing product, very commonly used in jets and other aircraft some newer cars have started using this technology to gain crazy increases in structual rigidity of the chassis. The new for expidition through use of this foam gained 70% increase in chassis rigidity over last years model. A couple cadillacs and some Benzs also use this technology but more for sound deadening more than chassis stiffening.

Just check out these links.

They foamed the chassis of a 300zx with the least dense foam and increased chassis rigidity by 40%
http://www.sportcompactcarweb.com/pr...scc_proj300zx/
its down towards the bottom

this is an example of the stuff... the foam used in the 300zx was 2lbs per cubic foot density. On this site they have up to 16lbs per cubic foot density which is 1500% stronger than the 2lb stuff.
http://www.shopmaninc.com/foam.html

I could see using this stuff in strategic locations on the car to act like a roll cage and I was thinking about foaming the SFCs that I want to put on.

SO who knows about this stuf. I cant really find any info on it. It doesnt seem like many cars use it. Maybe theres a reason for that, that I'm not aware of.

 

http://filebox.vt.edu/t/tjohnsru/1999-01-1785.pdf

 

Hmmm... not much interest. I must be missing something. When I heard about the this I found it very exciting. It is used in Rally cars as well as some other racing events.
The only thing I found is that it is flammable, not something I want in my car and if you were to fill your chassis bumper to bumper and you got into an accident, all of a sudden your repair would be nearly impossible. I was thinking about using strategically around the drivers cabin more for safety, and noise reduction, but adding regidity to the chassis would be cool too. I was thinkin side impact protection might be helped by this as our maxes are not known to be great in side impacts from what I've heard.

The miata guys have been foaming their chassis for a while and report great improvements with the foam

I am surprised this hasent caught anyones eye

 

Search the Auto-X and Road Course forums, I remember at least a discussion or two about this a while back. If not, just post this there, those guys may not all have done it, but would be able to give ya more details than most in this forum.

 

not sure if i like the trade off!!!

If insurance were to find out that this type of stuff was in the car, and you were to get into an accident, and the adjuster comes out, not sure if they would like this idea and may deny your claim.

 

Very funny Avtar puppet... anybody you know???

 

It was probably someone named Jason. (inside joke)

 

Any how much will your car weigh after that? 200-300 pounds extra?

 

probably 50 or so. The volume available in the areas he's talking about is minimal. It is also low and should lower the center of gravity. Sure, it'll slow it down in a 1/4 mile, but should help in a corner.

 

It would be 50lbs MAX. The 300zx that they did, that I linked to only gained 10lbs from the foam, and supposedly that was pretty extensive.

But they used a light foam. I would use a denser foam. Probably 4-8lbs instead of 2lbs like what was used in the 300zx

 

Not at all, that foam is VERY light... The huge rims you put on kill MUCH more performance that foam ever could.

 

Im pretty sure that the Ford F-Series uses this stuff currently but thiers is heat activated... I doubt an insurance adjuster like me would know if this was standard equipment...

 

as stated above, we had a long discussion of this in the autocross forums earlier in summer of 05.......the upsides are obvious...the downsides were:
1. there is a risk of actually bending the frame if you don't have enough/correct expansion holes for the foam.
2. very very few shops can or will do this - trust me, I've asked around quite a few.
3. remember, this is a permanent mod. If you do it and don't like it...tough luck, it cannot and will not ever come out.

All that said, I'm still looking into doing it in place of SFC's.....I believe Matt Blehm (Matt93SE) has done some of it to his 3rd gen, but I don't know of anyone else.

 

I would not add structural foam for the purpose of safety. Manufactures spend millions of dollars on research to design the structure to crumple and absorb the impact in the event of a crash. If you change any of the crumple zones, you could compromise you and your passengers safety.

 

Interesting point. I assume SFCs would affect the crumple zones as well then? But maybe to a different degree?

 

They could, but consider where the SFC's are mounted, underneath the car. They could, I suppose, affect a side impact if it was hard enough. They are not going to affect a front or rear impact, and if they do, well, your gonna have cabin intrusion at that point and your pretty well screwed. I'm not saying the foam won't help with structural rigidity, I'm just saying that I would not use to to help safety wise.

 

Car manufacturers also try to keeps costs as low as possible when making a car, so sometimes they do sacrifice potential safety to save money. And I dont care how much engineering goes into the car when it comes to side impacts. I would rather get severe whiplash and get thrown around extra hard in the cabin if I was hit from the side than having the door come in a break my hip femur ect. Thats where I see the foam helping a lot.. All the people that I know who have gotten really injured from car accident were from getting t boned.

 

Might wanna do more research on the Q45 and the "few other premium cars" that he is referring to. See if you can find details on their foam filling and possible safety precautions, issues, etc. The other article that Nismonoob posted is pretty interesting, but it was done on a stripped down car and no road tests (and I assume collision tests) were done.