Foamed Chassis Impressions.

[98sr20ve]

I foamed my 92 240 SX today. If you don't know what that is read this. (http://www.sportcompactcarweb.com/projectcars/0006scc_proj300zx/) I did the unibody area that connects the strut to the A pillar and then the cavity that runs between the front and rear tires, right under the edge of the doors. Most cars have a cavity in that area. On the 240 it is about 3X3 inch's. No wires were running in any of these areas. I had to remove seats, pull the carpet back, remove the rear panels. The rear panels kinda fool you. That cavity seems to not be there but if you look carefully you will find some holes that lead into the boxed in frame area. I didn't run into any major problems. You need to be sure to remove the seatbelts and everything that occupies that cavity before you put the foam into it. This is basically what I did in the door sill area.
http://www.sportcompactcarweb.com/projectcars/0006scc_proj300zx06_zoom.jpg

This is a picture of the finished trimed area by the strut towers/a pillar.

http://www.zilvia.net/photo/data/501/0Pict0039.jpg

Then you have to cut the stuff out of the areas that you need the seat belts and that stuff to go back into.

Now the good part. The stuff just plan works. The car feels 10 years newer. It takes sharp bumps/broken pavement with a thump rather then a shutter, the car is quieter and just feels more composed. You notice the change right away. When I ussually jack the car up I can see the frame bow. I notice this on every car I work on. Once you look for it you will see it. Right after doing this I jacked the car up and it moved so much less it shocked me. I am 100% pleased. My wife really likes the change as well. This gets
:fruit::fruit::fruit::fruit::fruit: from me. In the end I used $100 worth of foam. I used two II-22's and one II-12. For more info on where to get the foam look here. (http://www.sr20forum.com/showthread.php?t=95522)

[Loofee95SE]

huh?? educate me ....WHY??

[98sr20ve]

huh?? educate me ....WHY??

Read the links.

[mrmephistopheles]

cool stuff. got any more pics?

[BoroBoroS13]

I want to do that shit but im pretty sure I would get my hand stuck to the car or something. Hehehehe

[Loofee95SE]

where did u get the foam stuff?? after I red that ..it sound like a good alternative. ( sorry I didn't see the link earlier. C Need more pics please.

[projectRDM]

I did all the roof pillars in my old S14, it's damn messy if you're not careful, but it's a pretty good way to cancel out noise and tighten the chassis up. I taped up all the holes really well and then sprayed from the top, letting it run down into the pillar. I attempted to do the rocker panels too but I didn't tape well and lost a lot of it.

A lot of new cars come with foam filling from the factory now, Infiniti uses it heavily in the Q45.

I took a new route with the new car, I gutted it out and had spray-in bedliner laid down throughout the entire interior, from the footwells back to the trunk. Before spraying it I taped up all the swiss cheese holes everywhere, including the e-brake cable holes and rear speaker holes, the liner lays down over the top of it and makes it solid. Does a good job of sound deadening and cancelling out resonance, also helps to insulate a little from heat/cold. With the car back together it gives a much nicer feel, but I plan to go back in with a roll of carpet underpadding and stuff the rear quarters full of it, and lay down a few layers behind the other panels and carpet. It's amazing how much more soild a car feels when it's quieter.

[old_s13]

i have a feeling that this impression you guys feel with foam is noise cancellation, not chassis stiffening. i think if you truly want to stiffen the chassis, it will involve seam/stitch welding and/or chassis bracing.

while i dont see this as a complete waste of time, i think foam cant do much in terms of actually stiffening the chassis.. more noise cancellation if anything.

[tastyratz]

damn its about someone tried it on an s13! that was always the big plan for me to do this but it was few and far between. ive posted in a few threads on this before if you search under my name for it... it might be part of the winter project with my car too :-)

[98sr20ve]

i have a feeling that this impression you guys feel with foam is noise cancellation, not chassis stiffening. i think if you truly want to stiffen the chassis, it will involve seam/stitch welding and/or chassis bracing.


I know you are wrong. You can feel it as you back out of the driveway at an angle. The car is stiffer. No doubt about it. Plus, you can tell when you jack the car off the ground. Sure, its quieter. Nothing wrong with that. This foam is stiff stuff.

[derux]

I had foam on one of my other cars and every where around where the foam was the car had rust. It is like the foam can hold in the water and not let it dry then the rust begins and rust never sleeps.

my $.02

[projectRDM]

I had foam on one of my other cars and every where around where the foam was the car had rust. It is like the foam can hold in the water and not let it dry then the rust begins and rust never sleeps.

my $.02

That was the part I left out. Doing the rocker panels will definitely hold in mositure, because that's where the sunroof drains into and by filling the cavity you close up the drain holes. The rest of the areas should be ok but a good coat of primer over them wouldn't hurt.

[tastyratz]

dude if you look at some old threads i posted on this i put links somewhere on where to get 6 lb density foam. 1.75lb is what you got and not really that strong. something 4-6 lbs is adequate for what we need it for. 2lbs or under is more "audio grade" than anything else really... ill probabbly use stuff that light in areas like my hatch for a quality low weight solution to get some better sound in my car but i wouldnt use something that light for stiffening. look on some miata boards youll find more info on this, ive been reading on this for a very long time and its something most people skip over and dont realize...

[Sil Beer S13]

that stuff will retain water and start to get all gross and heavy.

[Shin_Kudo]

There's actually a test for the effectiveness of the foam treatment. Before foaming, put a piece of tape across the crack between the door and the rear fender, and mark a line across it, then cut it. Jack up the car, and see how much the line misaligns, and mark it again. Do the same once the car is foamed, and the line will hardly move at all.

http://driftpimps.com/forums/viewtopic.php?t=193

[98sr20ve]

dude if you look at some old threads i posted on this i put links somewhere on where to get 6 lb density foam. 1.75lb is what you got and not really that strong.

This is more then fine for this purpose. Could you go with denser stuff. Yes, but you also run the risk of bowing out the panels when it expands. This added a small amount of weight. The 6 lbs stuff would be far more then I would be willing to add to the car. At that weight I might as well do a real cage.

That was the part I left out. Doing the rocker panels will definitely hold in mositure, because that's where the sunroof drains into and by filling the cavity you close up the drain holes. The rest of the areas should be ok but a good coat of primer over them wouldn't hurt.

No sunroof on this car. You do need to pook a hole thru the two drain channels for the wiper area. The area I did under the floorboards is part of the inside of the car. It's sealed to the outside.

I had foam on one of my other cars and every where around where the foam was the car had rust. It is like the foam can hold in the water and not let it dry then the rust begins and rust never sleeps.

my $.02

Let me guess, you used a single step spray can. This is not your average Home Depot product. It cost 4 times as much and does not absorb water. I have heard of it being used as a floatation product on boats

[old_s13]

I know you are wrong. You can feel it as you back out of the driveway at an angle. The car is stiffer. No doubt about it. Plus, you can tell when you jack the car off the ground. Sure, its quieter. Nothing wrong with that. This foam is stiff stuff.

if so, cool.. i leave it to you, its your car and i wish you luck. im not hating, im just sceptical thats all.. and why shouldnt i be? i just dont expect much out of foam. for me, if i want to strengthen metal i use... more metal.

like i said, from an insulating standpoint that looks really good. for me, i know i plan on using braces and other metal supports to make the chassis stiffer, and i'll be using more carpet padding to cancel the unwanted cabin noise later down the road.

- mike

[98sr20ve]

if so, cool.. i leave it to you, its your car and i wish you luck. im not hating, im just sceptical thats all.. and why shouldnt i be? i just dont expect much out of foam. for me, if i want to strengthen metal i use... more metal.

like i said, from an insulating standpoint that looks really good. for me, i know i plan on using braces and other metal supports to make the chassis stiffer, and i'll be using more carpet padding to cancel the unwanted cabin noise later down the road.

- mike

People have done research on the strength benifits of foam. It's in published automotive trade journals. For the sub 8lbs I added I don't think you could get more bang for you buck from a weight vs stiffening vs noise point of view.

[thx247]

People have done research on the strength benifits of foam. It's in published automotive trade journals. For the sub 8lbs I added I don't think you could get more bang for you buck from a weight vs stiffening vs noise point of view.


So far everything we've seen in this thread is verbatim what you can read on the Sports compact car article. Got any linky?

[98sr20ve]

So far everything we've seen in this thread is verbatim what you can read on the Sports compact car article. Got any linky?

Why, you think Kojima was lying? Do a google search.

Page 3 of the dow.com link.

http://www.dow.com/webapps/lit/litorder.asp?filepath=automotive/pdfs/noreg/299-50624.pdf&pdf=true

http://www.miata.net/products/chassis/bellco.html

http://www.splparts.com/Parts/S14/Suspension/Bracing/default.asp

http://www.rmi.org/sitepages/pid774.php