I've had a few requests for the JUN Foam (form) kit. So here it is! Sorry as this was supposed to be up last night but I was stuck tuining some cars and couldn't get to it.... I apologize for the long story, but I want to try to get as much info to you as possible. I hope this helps those that were asking about this, and those who might have never thought about it till now.

"FORMING URETHANE REINFORCEMENT KIT
It is said that a too hard body is not good. A reason is for a maker to perform shock absorption considered for safety.
A body will transmit various information to each part, if rigidity improves. But if body reinforcement is actually performed, wages will become a large sum for reinforcing roll bar spot increase, reliance board reinforcement, etc.
Also it is difficult to imagine what effect it induces. Then, the epoch-making body reinforcement item which can be felt at low cost was developed.
This new reinforcement method makes high rigidity feel simply, so that it reverses old common sense. The car which performed urethane body reinforcement can feel the difference, when it get in and departs, you feel a motion of a car. The car which has constructed the roll cage etc. is still more effective. Although there is a difference in the ratio of an effect also by the new car or the old vehicle, rigidity is raised certainly."- JUN website

The Story: I purchased my foam from a local chemical shop, I had them special order it. Basically, it is a two part foam that you mix together and pour into the chassis. I originally got the foam bug after reading an article in Options about three years ago. Now, you may scoff me for doing this,but it honestly does make the chassis more rigid. (side note: Infinity comes stock with this foamed up chassis)
I got my kit and raced home to start the process, I started early to avoid any "Damn it's." I did this procedure in the early part of summer (about 70-80 degrees) to aid in set time. I had a painter's pail sitting around from when I was painting my friend's car, so I grabbed that and read the mixing instructions. My first attempt at mixing the product went well, I knew that there was little time to get the mix into the chassis so I pured feverishly into one of the open body cavities. I got some on the floor accidently in my haste, "Oh well... I'll clean it up later." <--- this would prove to be more difficult than I thought later. The foam set rather quickly, just under two minutes I'd say. The foam expanded and grew into all the crevaces.
I had originally not liked the large open holes along the floor of my car, so I covered them in carbonfiber mat. The foam pressed against the mat,but did not break it from the metal. When I got the foam to the upper hole it tended to seep over the edge into the cabin. I made a cardboard template and used that to keep the foam going where I wanted. I found that it is helpful to use masking tape to plug the tops of holes to prevent the material from expanding into places it should not be.
Upon getting to the upper portion of the chassis, I found a small funnel to be useful for the first few pours. It became quickly obstructed by the foam. I then found it useful to stick the funnel into a small cup of paint thinner to keep the foam from expanding and obstructing the spout. You can see in some of the pictures that I got foam resin, and excess foam on parts of the car. Remember, I did this over two years ago and that resin is still there. Don't let it set for very long if you need to clean it up!
So there's a summary of the story, a little insight into my day and the joy of JUN foam.
The Benifit: After the foam had set for a few hours, I took the car out for some testing. I had taken all my suspension parts off the car, with exception to the shocks/springs I was using at that time. Immeadiatly,I noticed a difference. The car was stiffer and more responsive to what I did. It seemed like the body was moving more as a whole, instead of twising and refusing to corner. Understeer was noted and would require more tuning, I'd never had this issue with a stock chassis. I basically would call this a poor man's roll cage on suspension only, it does not offer any protection like a cage would.

The pics:

 

Another product to concider, but i have not tried, is ITW's foamseal. It is the same stuff used by Sport Compact Car on their 300Z project:

http://www.itwfoamseal.com/auto_aftermarket.htm

 

Is this the same foam used for boats?
Same stuff right? but with the JUN can..

 

i read this and i read the SCC article about it and i still don't get one thing, where do you put this?

 

It's basically 2lb per sq. ft. foam. I think it's for boats... kinda wished I would have known that before I started. The foam goes into the cavities of the chassis. I guess you could put this in your doors, but that seems dumb. But all those holes in the metal inside your driver's compartment... that's where it goes.

 

sound like the same stuff they use to make surf boards...

 

Hey advan..
do you remember how much liquid was in each of those containers??? both mixed together = 1 cu ft right???