I recently filled all of my motor mounts with liquid polyurethane (60a) and installed them. I was under the impression that because I was using 60a and not one of the higher ones like 80 or 90 that I would have a nice balance between performance and comfort for a DD....I was wrong. They do keep the engine in place and help it perform a lot better but the cabin vibration is ridiculous. Way too much for a DD. So I was thinking about trading some of them back for new stock mounts but just wanted to know which mounts you guys think transfer the most cabin vibration as I don't want to replace ALL of them. So while keeping some of the polys, which ones would take away most of the vibration if traded back to stock? I was thinking the rear mount just because it's right up against the firewall.

 

If you think 60a is bad try daily driving one with 75a and nearly solid torque mounts, everything shakes and rattle, dash, mirrors panels, etc...lol

I have driven other peoples cars with even stiffer mounts than 75a and it gets really annoying after awhile.

From what I have read online in the past, most people swap the rear mount to a stock/stock style one and that eliminates a majority of the vibrations most people complain about.

 

Thanks, I think that's what I'm going to do. On top of switching the rear back to a stock mount I may drill two holes in each of the lowers as well

 

hmmm dow window weld worked great for me.
a little on the stiff side but nothing crazy.
yours maybe didnt have 300k+ like mine tho lol.
torque mounts were completely knackered.

2 X DOW U-428+ Auto Glass Windshield Urethane Primerless Adhesive Glue Sealant | eBay

drilling is a good idea, hadnt thought of that.
always great to encounter another cheapskate mind that thinks outside the box.
respect! 8)

 

Oh trust me...mine were chewing gum lol. That's why I did this. I didn't let anyone drive my car just because of how bad the mounts were. If they didn't feather the clutch just right the engine was all over the place. Anyway, that's completely fixed now it's just the noise and vibration is pretty bad. Window weld seems like a good idea and maybe I shoulda done that in the first place...But I think I'm going to try to drill holes in the two lowers to make them look more like the oem mounts and then change out the rear mount with an actual oem since that seems to be the trouble maker. I figure if I do that, I still have 4 polyurethane mounts for better performance but I'll dampen a good bit of that vibration. But yea, I'm all about being thrifty and doing these little DIY projects. I just the other day pressed in my own suspension bushings with a long bolt, washers, etc.

 

https://www.mcmaster.com/#liquid-urethane/=19ol6ll

I think I want to buy a gallon of either 20a or 40a and fill my mounts with that. Should be a better compromise than window weld.

 

From what I understand, anything below 60a for polyurethane will not hold up over time. It'll prematurely brake down. If you're set on pouring your own mounts (which is a fun project and can turn out really well) but you also want minimal cabin vibration then I would recommend only doing the lower two torque mounts otherwise you'll get a pretty decent amount of cabin vibration. You could also drill holes in them once the poly has cured and that would help dampen a little bit. Here's a GREAT resource to learn the proper way to do these - LINK. Also make sure to torque the mounts down in the correct order when you re-install them according to the Honda service manual.