I just installed Prothane motor and trans mounts. I was installing headers, so I thought this would be the perfect opportunity to do it. I consider myself to be a pretty decent shadetree mechanic, but the motor mounts were a bitch. I did it without removing the A/C compressor or alternator. I just had the exhaust out and removed the starter.

I have not yet put the car back on the ground because I am still installing other **** right now. The mounts look seriously badass and heavy-duty. I too will report on the performance of the poly mounts.

Get your mounts from Thunder Racing! I ordered them on a Monday and they were sitting on my doorstep the very next day on Tuesday. It was like $80 for all 3 mounts shipped from door to door. Best of luck!

 

I voted "No" 'cause you should install solid mounts. You've got an exaust already, so any added noise will be barely noticable over your muffler, or lack there of.

 

Have you ever ran poly mounts on these cars? They have all the benefits of solid mounts, and none of the side effects.

Ever tried to pull a tranny with solid motor mounts? Good luck tilting the motor to remove the top bolts.....

Solid mounts are for racecars OR people who dont want their motor to move 1/32". Poly mounts are perfect for street machines IMO.

 

I started a new thread on my poly install today. I will chime in and say do it as well. Very noticeable difference. I only did the driver side and tranny mount, and it took five hours. It wasn't much fun, but it paid off. I asked these questions in my thread, but I'll ask them here as well. First, are there any drawbacks to not doing the passenger side? Also, on the tranny mount....I didn't put the bracket in that was on the original mount. The black bracket that was sandwiched between the original mount and the tranny. Is this going to be an issue? I simply put the poly mount in the way it came from Thunder Racing. Any input is appreciated.

 

I have a set of sphoon solid mnts I am thinking of putting in or not. I did not think about the tilting the trans back thing.... I KNOW I will have the tranny out a few times over the next few years.

Are poly mnts as good as solid? Maybe I should send them back for the poly ones. The motor is all the way apart and I'm at this stage NOW.

 

Solids in my DD too. And yeah 99% of anyone who rides in it can't tell i have them.

 

Yes all the time. Just loosen the back four 18mm bolts holding your K member in and the tranny drops just as far as it would with stock motor mounts. adds a whole extra 5 min to a tranny swap.

 

Is it really that easy? That don't sound that bad.

 

Yes it is. and belive me i have pulled a tranny out of my car more times than i care to admit.

 

I'm sure it will be an every other or every year kinda thing. I think owning a M6 and beating the **** out of it will cause one to do regular tranny matinance and or clutch changes.

 

Lots of people run just one side motor mount, to keep it from tweaking over sideways. Not sure which side tweaks up and which goes down though

That black piece on the stock trans mount does not come off, the poly one just bolts on in its place. You are also NOT supossed to use that metal shim that it comes with on a 4l60e/t56. I think these mounts can be used on all kind of applications, and the shim is needed for some.


I could just see my *** trying to bench press a nice LS1/T56/k-member/a-arms combo!


The T-56 is usually completly fine, it just dishes out the pain on everything else! (differentials, axles, driveshafts, :cough:other cars:/cough: )

 

The distinction between race car and street car varies from person to person. Almost all the modifications we discuss in these forums effect noise vibration harshness (NVH). As far as these modifications go, solid motor mounts are mild in my opinion. On a scale of 1-10, 10 being most adverse to NVH, I rate the following from my experience:

Typical cat back muffler: 2
Delete Catalytic convertor, retain muffler: 8
no exhaust: 9, maybe 10
Remove intake baffling (lid): 2
Loppy cam, idle: 5
Remove sound deadening: 3
poly motor mount: 2
solid motor mount: 3

The question is, how closely do you want to "feel" the car? And, I may choose to switch to poly (or even stock rubber) mounts in the future. I should have stated in my last post, that anyone debating poly or solid mounts should make an effort to test drive a car with similar modifications first if possible.

 

I am fully aware of this, which is why I inserted the "IMO".

This topic is almost as trivial as the y-pipe vs. true duals thread.

 

I did my drivers side today, took our time and it wasnt as bad as I thought it was going to be as long as you have the right tools. No more vibration at idle and no more banging exhaust.

 

I just installed solid motor mounts tonight. They look very stout.

 

Solid mounts on a DD ?, ok some like to feel the car more..lol, yes you will feel the car more. Meaning the vibration from the motor. Will it rattle the dash, no, not unless your car is a pos. Will it vibrate the stick shift and steering wheel, hell yes. How much you can stand that is the determining factor as to if you think the'yre ok. I have one poly mount on the drivers side. Thats all it needs. I have heads, cam, lt's and a good amount of torque and hp. I would never do solid mounts in my DD, dont need it at all. In a track car I can see it. Do the poly's first. If your engine is still jumping around then look at solids. I have original factory trans mount still. Do the trans mount and you'll feel even more vibration on the stick. Most all the banging people get is the factory motor mount being no good. They are soft rubber and tear.

 

Thats odd cause my solid mounts don't viberate or shake anything. I've put in five sets of solid mounts and NONE of them could tell i had put them in.

 

Then your motor must be the most balanced engine around because I can tell the difference with just poly mounts and a 224/224 112 lsa cam. I can feel the rumble of the exaust better as well so you either full of it or can make a house of cards on your intake.

 

Actually a car will rock more with stock or poly mounts than with solid mounts. A couple guys i put the solids in were hoping for the car to rock hard core. but were dissapointed when it actually rocked the same. the motor was completely still though.
You can feel the car better and feel the rumble of the exhaust but i wouldn't call that shaking or viberating.

 

I have heard nothing but good things and I already have mine waiting to be installed.