my engine has been rocking over the last year since i installed the stage 3 clutch. now, the SC rocks my engine's world even more.

sikbrik had sent me some 60A polyurethane last year.
spur of the moment, i decided to fill the engine mounts on thursday night. after a few hours of raging and cursing (known lubricants for stubborn parts), i got the rear and driver's side mounts out.

i removed the thin rubber to open the whole way through. then i cleaned the rubber with grease cutter and dish detergent followed by alcohol. i roughed up the rubber with sand paper and a metal file.

i taped up one side and started pouring the polyurethane in and waiting for it to work its way to the other side. i shook it to work out some air bubbles. then i filled it up and taped up the open side. the first mount took long enough for the polyurethane to start hardening, so i had to do the second mount slightly differently.

i filled the second mount as before, and taped up the open side, but then i took off the tape on the first side as the polyurethane had not reached through. i filled that side.

i let it sit for fourteen hours before raging the mounts back into the car.
the polyurethane takes about 48 hours to reach 80-90% strength and 72 or so for 100%. i had to drive it after 34 hours this morning. i took it lightly, but i could tell that the improvement was incredible. the noise increase was minimal because i did not notice much if anything. engine vibrations, however, are much more apparent, especially when it idles roughly. shifts and the general feel are really smooth now. no more rocking or clanking around!

i took some pictures of the mounts and a couple of mystery parts.
do any of you know what the block is for?
how about the rubber cylinder on the side of the rear mount?

http://www.hatefullyyours.com/auto/xa/engine_mounts/

 

btw, there is a rubber primer that can be used to bond the polyurethane to the rubber. if you plan on doing this, then you should probably get that too.

 

you gonna go the tranny mount too?

 

the transaxle and engine bolt together and are mounted to the chassis at three points:
1) bottom rear center
2) middle front driver's side (transaxle)
3) top middle passenger's side

i filled both 1 and 2.
i do not know whether 3 matters or whether it can be filled.

is there another mount to which you refer?

i would like to get some more road feedback. i heard that the power steering mounts on some cars can be replaced with polyurethane for that effect.

 

this is a sweet mod. I'm glad the stuff worked out for you...too bad mine is gone now

I'm surprised this thread hasn't seen more action. This definitely seems like a 'must' for performance and cheaper than anything else out there.

Keep having fun with the beast!

 

man i need to do this, itd prob help alot when i hit the nos lol

 

I used to do subframe bushings on bmw's same way, with Devcon Flexthane 90ish durometer polyurethane from Granger Supply, worked well.

 

where can i get that poly at? cuz i have no idea what granger is lol

 

http://www.mcmaster.com/
that is where sikbrik bought the liquid. one pound was at least twice the necessary quantity to fill the mounts as i described. if you get that much, be sure to have over thngs to make otherwise you will waste a lot. if i had planned better, i would have tried to make some washers to better mount my rear coilover perches.

now that i have driven it more, there is a noticeable engine noise increase, but it is not huge. it will not require you to yell or turn your music up really loud. i like to hear the engine.
i can feel the engine a lot more now, which is generally fine. the rough idle is really apparent though.

the unpredictable rocking and throttle modulation in low gears is practically nil now!

 

If you guys can wait a couple of weeks, I have Energy Suspension prototyping up some engine mounts... both full replacements as well as easy-to-install inserts.

Should be a no-brainer and an easy upgrade.

 

I use good old window weld for all my motor mounts. Comes in a culk tube. Tape off the one side, inject it and make sure to fill it totally. I stick it in an old oven at 190F for about 24 hours and have never had an issue and feel / improvement is amazing. Cost a whopping $13.00 for a pair of mounts usually haha. Never had one rip or have any issues.

 

is it necessary to bake this? window weld is just the urethane used to install windshields, right?

 

Correct. It has been used for years with us... budget racers hahaha. Workes AWSOME. Also no, I bake it because I want it to cure faster Not absolutley needed.

 

thanks, im definitly going to do this. it will be a while before the motor is back in my car, so i will have plenty of time. anything i should be careful with when doing this?

 

Just do not get it on your hands... you will not get it off *LOL* same with clothing obviously... stuff is NASTY.

 

thanks for the tips, when i do it, ill take pics and post them up

 

where can you get that stuff at?

 

the polyurethane is not expensive. one pound was twenty something and it is enough to do four to six mounts.

if the caulk tube stuff works just as well, then i would recommend that because the proper amount for the job can be dispensed without ruining the rest.. the polyurethane needs to be mixed completely, which can be wasteful, or you can attempt to measure out the activator and substrate for the task, which could be difficult.

 

The stuff I use you can get at most checker, shucks or kragen stores. It is called "window weld"

 

Another good option is urethane window caulking available at any hardware store for around $5 a tube. Just use caulking gun and shoot it in there. I don't even think you really have to clean anything, this stuff sticks and never comes off.