Urathane Mounts

[heefner]

I installed the urathane mounts yesterday and we I started the car it was like somebody shove a quarter in the slot.  The car vibrates terribly.  I have the balance shafts removed and it was supposed to be balnced and blue printed by EIP.  Has anyone else put these in.  I put all the mounts in.  Engine, tranny and rear.  It was a pain in the arse!  I was swaping out the 86 rear for an 88 so I had to do all the work anyway but man, I would hate to change them just to change them.

[PiercedJD]

my motor mounts are a custom setup using polyeurothane inserts, I don't think it's unbearable, but there is more vibration than with a sloppy rubber mount, but at the same time the entire car is gonna move before the engine shifts in the chassis, and that to me is a bonus. controlled weight transfer is a good thing.

[Boosted_One]

I installed the urathane mounts yesterday and we I started the car it was like somebody shove a quarter in the slot.  The car vibrates terribly.  I have the balance shafts removed and it was supposed to be balnced and blue printed by EIP.  Has anyone else put these in.  I put all the mounts in.  Engine, tranny and rear.  It was a pain in the arse!  I was swaping out the 86 rear for an 88 so I had to do all the work anyway but man, I would hate to change them just to change them.

 

 

That's how poly mounts are.... I've installed those mounts in several different cars and yes it is more rattling at times. I have my poly motor mounts in but haven't driven the car yet, but I know what to expect also...

 

If you seen how my engine shook at idle even with new OEM motor mounts...let alone a good launch.

 

everything is a comprimise, much like swapping the stock suspension over to something firmer.

 

Those mounts will shine in moments you need them, trust me

[heefner]

I guess I didn't know what I was getting into.  I'm not sure I can get used to this.  I have some electrical bugs to work out and I have yet to get the clutch adjusted to were I can drive it on the street.  It just went from smoth as silk to riding a skate board on a coble stone street.

[Tim_C.]

Try solid steel! He He!  I drove a solid steel mount SBC in a '66 Nova for about 12 years.  I loved it.  Put them in the quest, and major vibration.  I want to just go poly on the motor mount, and maybe the others too if that doesn't cure it.  I might be sticking with the Solids because Otis isn't returning my E-Mails, and he said he could ship some mounts to me.  Haven't got them yet, so if they aren't here by next week, I will have to go with my solids for now.

Tim C.

[heefner]

Is there anything In between stock and the urathane I got from the GP.  How much improvement can I expect from these things in a drag race application.  Im seriously thinking of putting the stockers back in.  It don't think I'm gonna wan drive this thing on the street much the way it is.  I'll end up loosing parts on the freeway.  Its rattling my fillings.

[heefner]

will these things soften up any ?

[Chad]

they won't soften, thats the whole reason to go poly.  you might have some luck with one stock and one poly.

[zactek]

I put my poly rearend bushings in and definately feel more vibration, especially when letting go of the gas and letting the car coast. I'm starting to hear all kinds of noises coming from the rear, like whining. It's bearable and the drivetrain definately feels more solid.

[heefner]

I'm thinking about leaving the right side in and putting the stock one back in on teh driverside.  that way the engine wont pull away when it tourques but will be cushioned a little.

[heefner]

I drilled some holes (side to side) in a new stock motor mount and put 8 evenly spaced carrage bolts with some epoxy to hold them into the holes.  I don't know how much it helped to stiffen things up but it made me feel like I did something.  I put the stock tranny mount back in after I filled the empty space with epoxy.  I put the motor mount in on the passenger side leaving the urathane mount on the drivers side and both rear mounts in.  It helped to dampen the vibration a good bit.  Everything still feels really firm I just eliminated a very annoying and harsh vibration abetween 1600 and 1900 rpm.  From 2000 all the way to redline the vibration wasn't bad even with all the urathane mounts.

 

On a side note, I think the urathane used in these mounts is way to hard.  It atcually looked like the urathane was pulling away from the steal plates on motor and tranny mount after about 500 miles.

[Gary]

On a side note, I think the urathane used in these mounts is way to hard.  It atcually looked like the urathane was pulling away from the steal plates on motor and tranny mount after about 500 miles.

 

Thats doesn't seem to good, has anyone else seen this?

[Tim_C.]

I got my urethane mounts, and I don't think I can use them. Way too hard for a street driven application. These are road race mounts. I am actually getting used to my solid steels, and there isn't as much vibration now that I got it dialed in a little better.  But still, most guys would not put up with the vibration I get, and those poly mounts are just as if you welded up the stock ones like I did. I can see how they would seperate because of the stiffness is such that they would break before giving any.

All of the street quality, and even some race poly mounts I've seen aren't near as stiff as these. I am going to have to send mine back since I have the same stiffness and better for longevity with these welded ones.

The poly won't get any more pliable. The way they are is the way they will stay.

I can say that my solid mounts got rid of the wheel hop. I have all solid mounts except the passenger side motor mount. It comes off smooth now, when before it would hop. So, the poly mounts would be good to fix that if you aren't worried about the vibration. But for a lot less, you can weld them up.

Tim C.

[heefner]

I would have never guessed the words "smooth" and "solid steal mounts" would be used in the same sentence without the words "not very" mixed in.  Tim, your engnie must really be dialed in.  Is this car strictly street or will you be taking it to the track as well?  It sounds pretty bad a** and I'm curious to see some numbers.  Keep us posted.

[chiplee]

well this is getting to be a bummer.  I have all the poly mounts in and I think my car will start tomorrow and I don't want to have to swap rubber mounts back in.   there was a guy in the stall next to me at the hobby shop installing poly motor mount inserts in his honda and they were very pliable and flexible.  They were energy suspension I think.  I guess It's almost time to call steve and find out what give.  My motor was very very well balanced by Southern coast automotive machine in Theodore, AL.  So I'm going to see how it feels.  If for nothing else at least I'll be able to come here and add another voucher for the fact that these are too hard.  Not that we need it.  

[heefner]

:-/

[KevinL87tsi]

this isnt sounding good.. but i guess like mike said... everything is a compromise....

take the good with the bad.. either we keep the stock mounts and enjoy a smoooth ride yet take the slop with it.. or loose the slop and get a back massage at the same time .. the worst part about a shaky car is the interior parts that start to rattle.... i will install these poly mounts and give em a shot and let you guys know what i think

[chiplee]

I don't like it at all, it feels like the dash is going to fall into my lap.  I'm at least putting the rubber motor mounts back in.  Something has to give, I feel like I'll be chaseing broken bolts and loose nuts all over the car if I leave it like that.  The frame and body were not designed to be shaken that way.  Between 1200 and 2000 rpm is the worst.  I love the rest of the stuff and I have a feeling the poly tranny and rearend mounts will be good to go and will help alot with the weight transfer idea but I do drive the car on the street and I could never expect my girlfriend to ride in it and I'm dieing to show it off to her so unless I some how get real used to it real fast I'll be selling some poly mounts if anyone has a race only application they'd like to use them for.

[heefner]

Chip,

I heard this from a few people and it makes sense... if you change the motor mounts back to rubber, you need to change the tranny as well.  If the motor is rubber its gonna torque, if the tranny is rock solid as these mounts are the tranny will not torque.  Iis gonna be flexible on one end and solid at the other.  End result you get a lot of stress on the bell housing of the tranny.  I filled the center section of the tranny mount with silicone and epoxy combination to make it stiffer than factory but not nearly as stiff as the stedibanni.  I also only replaced one motor mount with the stedibanni mount.  Its better but I might swap out the other aswell.

[jinx]

what problem are you guys trying to solve with the poly mounts ?

Couldn't you just add a TORQUE STRAP ? ... and keep the soft quality feel of the oe mounts ?

I made one for my buick GN years ago, using a "dogbone".. some motor brace I found in a junkyard, that had rubber bushings at each end. Dunno where it originated. Later on vendors sold ratcheting nylon straps to containg the turbo v6 that tore away driver side motor mounts on the regular.

 

You could buy rear suspension bushings for the GN that helped your launch significantly. You could choose among several "hardness" (durometer??) grades. They were good quality and inexpensive. Might be possible to get same done for starquests if you talk to the "right" people

 

Smmothness and refinement weigh heavily with me, so balance shafts and rubber mounts will stay

[chiplee]

thanks for that input Jinx. that's something I'd be willing to try for sure.  I'd like to have the smooth feel back.  If you're into "smoothness and refinement" with gobs of power then you'd have loved the afternoon I spent tooling around in a Mercedes E-55 AMG  350HP 390lbsft torque, but torque is a staggering 332ftlbs at  just 2000rpm, 5 speed automatic, 18x9 rear 18x8 inch fronts  0-60/5.0, 1/4mile 13.5@104, topspeed around 180 according to car&driver, and just too many features and creature comforts to mention.  Reportedly faster than viper and C5 vette, viper is no challenge in the turns I guess.  It's my girlfriend's dad's car and he won't even let his own wife or son drive it.  He wanted me to try it out and I hesitated for about 2 seconds and then snatched the keys.  It's one of a very few white AMG models brought into the US, most are silver, and man what a car.  Soooo refined but so aggressive at the same time.  I told him if he's ever interested in getting rid of it that he had to ask me first.  Hopefully I'll win the lottery between now and then.   It just makes you feel good all over driving a car like that.  Power is so readily available at all speeds and all rpm settings but it senses your current driving style and adjusts throttle response accordingly.  It also won't let you lose control.  you can have it floored heading into a sharp turn and as soon as it senses slippage or wheel spin it stops accelerating.  From a stop however it will roast the tires because it can tell that that spin is not a danger to passenger safety, so it's still fun in every way.  4 doors to boot so you can take the family to dinner and tear up the track all in the same day.

 

check it out here:

http://www.mercedes.be/fr/amg/e55.htm

[JasonC]

I havent looked to closely yet, just got the motor out, but I am thinking of welding grade eights to the sides of the mount. Its hard to explain...ummmm. Well I have two plans

1. Weld in the bolts and leave about a 1/8-1/4" gap between the nut and the ear(that I will have to fab)that it goes through. This would give you smoothness at idle and cruise but when you stand on it it would pull to the nut and then stop.

2. Same as above but dont weeld the nut in place. Leave the nut off until you want to go to the track and the put it on and crank it down. Thing is I dont know how hard it will be to get to the bolt after its put together.

 

Anyway just thinking. I will post pics if I come up with something.

[chiplee]

I am currently using all the poly mounts except the passenger side motor mount, which is stock, and the vibration is very acceptable.  I did this when Mike K said that this configuration dampened 75% of the vibration, and now that it's done I completely agree with his estimate.

[Boosted_One]

The worst thing I have is the Gauge pod rattling on the dash now.

 

It is definetely stiffer than most would be used to but the motor and tranny feel like a locked unit now...and no more tranny hopping around. It is quite acceptable in what I am looking to get out of the car.

 

Glad to see you got good results Chip.

[chiplee]

sure did, and just to give credit where it's due, I know Chad recommended this a while back so thanks chad  it's a good idea either way but it was just nice to hear from someone who had tried it before I spent the hour on it.  Oh and mike I forgot to mention that I too no longer have any crunch going into 2nd, even when i shift as fast as I can.  I had gotten into the habit of double clutching, or at least shifting slow and now I can just rip it back into 2nd.  Also I now know what a bov is all about.  The power is right there waiting for you when you get back in the throttle.  Obviously I was having to build boost all over again with my (Let-the-car-drive-me) shifting style.  It's nice to be able to drive the car the way it should be driven.