Motor Mount Shore ratings(hardness)

DSMConvert

AWD...say Bye Bye
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Titanium MS6
Just thought I'd share my findings from the first stage of my motor mount experiment. Used my buddies old school dial gauge durometer he had at his shop to test the stock and window-weld materials. For the stock material, I didn't feel like tearing up the stock motor mount just yet so I cut 3 pieces out of my old msp motor mount(had 3500 miles on it before removed). for the window-weld I used the all famous 3m from autozone to make 3 chunks that cured for 1wk before testing.

Stock: 48, 51, 51
3M: 56,59,58

Please note this was on a dial gauge so there is probably a fudge factor of 1-2 as my eyes have a hard time counting the damn little lines.

Overall I was fairly suprised. Everyone swears that the 3M is a huge upgrade for motormounts. So naturally I did some looking around on the nissan and toyota boards and from what I was able to find all the posts and websites generally confirmed that the 3M was between 55-60 shore. I couldn't really find any specific numbers for the stock motor mounts on the mazda to confirm my results, but I did place a call to Anchor Mounts to see if they could give me any info(thus far haven't heard back). But being as that the 3M results were on the money I'm comfortable with assuming the stock mount numbers are also correct. Talked it over with a few friends and decided that the reason everyone swears by the 3M is that even though its around the same hardness, its the fact that the modification involves filing the mount solid, as opposed to leaving spaces like the stock mount does. None the less it was interesting info to note. So looked into different types of urethane mixtures and came across www.mcmaster.com references. So hopefully sometime next week I can begin stage II of my experiment, when my 80 shore rating urethane 2-part mixture arrives from McMaster. From asking around it seems 90 is the top for bearable street use, so I went with something in the middle as close to 75 as I could get. The goal is to put together a fairly informative How-To here in the next few weeks with results and such.

On that note if anyone happens to have the shore rating for energy's or ATP, or heck even **********s mounts that would be much appreciated. I thought I had an old energey suspension mount from my dsm but I can't find it anywhere and I don't feel like spending $40 to get one simply to flatten it.

Note on the 3M use: This stuff is very very thick and through my own lack of patience I found out first hand what happens when you rush and get airbubbles in the mix. My first "bad mold" pulled a whooping rating of 46. The best way I came up with to eliminate/minimize air bubbles was to do it in stages...We filled up a 2" x 3" x 1" box and I did it in 4 layers, using a screw to sort of stir up the layer before lettign it sit 5 minutes before putting the next layer on..

Input and suggestions always welcome...

Edit: Forgot to mention that the durometer is a Type A
 
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Another difference you have to take into account is that the stock mount has all those empty spaces in it so the force is concentrated on the four connection points. The aftermarket mounts use a solid material so the flex is less due to the even distribution.
 
McMaster part # 8644k11

Cool thanx gand that atleast gives me a starting point...

Kurf - please read all of my post, I noted exactly what you just said in my original post.
 
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hehe np, i figured you probably just skimmed...
80 shore mixture from mcmaster showed up today, so hopefully by the end of the week I can start with the fill process.
 
Never relized the 3M was that soft. When I filled the last cars the vibration was almost unbarable for me.

Good luck with the test and let us know.
 
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