Can anyone recommend a good chassis specific expanding foam? I want to make my cars a little stiffer I'd like to put it in the FC's frame rails.

 

I am looking for the same info myself

 

I've heard Urethane is a decent chemical to use. Part of my reasoning is that the FC chassis has lost some rigidness over the years, the expanding foam could potentially help restore and surpass it's original handling.

 

Check http://www.fgci.com

I've used their 2lb foam in chassis', worked great. It will quiet down some rattles etc. when hitting bumps. If your chassis is really loose you will notice the difference, mainly on bumps in a turn.

 

Hey thanks! which specific product do you recommend?

 

Click on the link, then 'catalog', then 'foams'. It will be the first one on the list of foams, 2.0lb liquid foam.

I would check with them because the 4 or 8 lb might be better in an older car. Do a search for closed cell urethane foam and dig around, I found some better websites with more info on physical properties, FiberGlass Coatings is just local to me.

 

Most marine stores carry 2 part urethane foam of different densities, I know West Marine carries it.

 

icemark did it
here:
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/those-think-i-dont-make-mistakes-those-know-better-foaming-frame-329353/

 

Adding in expanding foam is not going to increase chassis rigidity. It will make it more damped and quiet, and will also act as an insulator.