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View Full Version : pourable polyurethane as a structural foam alternative for rear floor/subframe? discuss!



slater
08-18-2014, 11:19 AM
i started this thread as i was looking to inject some of the BMW/Audi/Henkel non-expanding foam into the rear floor cavities, but finding the product both expensive and difficult to find. i don't have any cracks that i can see, and i will be installing some AKG 90A poly subframe mounts soon for both preventative maintenance and a performance improvement, but the foam seems like the right solution for preventing rear floor fatigue/damage.

in light of the downsides (cost and availability), what are folks' thoughts on using a pourable (non-expanding) polyurethane in these cavities? i have extensive experience with 80A pourable poly that i've used in many OE bushing cavities, and have not noted any serious expansion - i'd say, less than 3%. it is an easy product to work with, cheap, easy to get, and available in different durometers. it would, in theory, offer similar structural stiffness as the foam stuff, and would conform to the shape of the rear floor cavities, and would help ensure those rear subframe bolt inserts from rocking around and tearing spot welds.

here's the product, for reference: http://www.energysuspensionparts.com/proddetail.asp?prod=DIYMMI

thoughts?

peter

Avetiso
08-18-2014, 03:44 PM
Excellent idea, but why? Our cars rarely break subframes. Only facelift I know is Wyatt, and he drives his car like a maniac.

slater
08-18-2014, 05:27 PM
Excellent idea, but why? Our cars rarely break subframes. Only facelift I know is Wyatt, and he drives his car like a maniac.

good preventative maintenance... and i would like to get to the track at some point. i'd rather prepare for it and not need it, then deal with cracking.

peter