suspension ramblings...

[kmack]

I should have heeded all of you guys' advice long ago, but the cheap-bastard in me steadfastly disagreed.

Urethane bushings ROCK!!!

I was in the process of changing my old rubber brake lines to braided stainless when I got to looking seriously at the 1 year old rubber bushings on my sway bars. "Man those things look like they're 20 years old!", is what came to mind. So a quick trip down to PepBoys for a set of Energy Suspension urethane end link bushings ($9.70 w/ tax) and I'm set. Keep in mind, at this same time I'm also swapping old, tired, stock springs for a set of new performance springs (bought from another z'er, so I don't remember the brand name).

So now here is what I have:

SS brake lines

EBC Green Stuff pads (front)

Raybestos shoes (rear)

Performance springs (stiffer and shorter)

generic strut carts. (yes I know, they're next on the list)

urethane sway-bar bushings

Reaction? I have a totally new car compared to what I had on Sunday!!! OMG!!! Why didn't all you guys that swear by urethane bushings smack me in the head earlier? Rubber bushings suck......

[Bambikiller240]

Kenneth, consider yourself head-smacked!

Now you need urethane control arm bushings when you replace the strut carts, to complete the transformation.

[2ManyZs]

:stupid::stupid: :stupid: :stupid:

Nuff said?????

Don't know who made the springs as they are MSA's "Motorsport Springs".....

Now you need to do the rest of the bushings in urethane......:devious:

[kmack]

I already have the adjustable control arm bushings, which I presume are urethane (or some other form of very hard plastic).

The rear control arms are next on the list, too. With adjustable bushings.

I'm going to be "testing" everything out on Saturday during a "Driver's Education" event. Really it's just an over-grown AutoX layed out on an old airport's runways. 1 lap is 1.8 miles. I know how the old suspension sucked, now I'll see how much better this new setup is.

[2ManyZs]

Uh huh... but don't forget the mustache bar bushings and the infamous spindle pin bushings....

[kmack]

I hadn't forgot. Just didn't want to think about those at the moment. They are too hard to deal with, ya know.....

[kmack]

Keep in mind I have an early series car. So I don't have the bushings you have at the transmission. I just have one single rubber mount attached to the transmission. The bar that bolts up to the body, is bolted up from the bottom (not the side) with no bushings what-so-ever.

So here's a question....

What would happen is you elimenated the rubber engine and tranny mounts for hard, fixed mounts? Does there have to be some flex to help with the torque of the motor? Or can the engine and tranny be hard-mounted to try and transfer that energy back into the driveline?

[ecp48]

mperdue,

for some odd reason energy suspension only puts the tranny crossmember bushings on the 74.5 to 78 kits.

I was begining to think the early crossmember was different.

Another oddity in the ES kits are the instructions for saving the sleeves on the front and rear control arms, both of which I found out the hard way (after removing the rubber) have to be removed. The arm is the sleeve. They do work!

ecp48

[trs]

my Z has recently had its rubber transmission mount exchanged for a solid type mount.(engine mounts solid as well)

Havent driven around in it yet, but id expect there to be more transmission "feel" offset by increased gearstick wobble/vibration.

[Z Kid]

If your engine and transmission is mounted solidly, any torque from the motor goes directly into the frame, so surely this must increase the chances of stress fractures etc? Also vibrations and noises would be a problem. I can't see the logic behind it on a car which you want drivable, and not have your teeth shaken out of your head?

[trs]

Our car will be primarily a track car..so NVH and comfort wasnt very high on the list of priorities.

there are probably some other benefits for solid engine/tranny mounting such as:

*increased acceleration response (less weight shift)

*slight increase in torsional rigidity of front end?*(just a guess here )

I have tried out solid mounts on other more modern cars (vw golf vr6) and the difference on that car in particular was very noticeable. There was a slight increase in vibration however definitely not unbearable. The whole car definitely felt a lot more "solid" and seemed to react better to inputs.

Just out of interest, i believe the new 350z uses a solid type transmission mount. They justify the increased gearstick wobble by saying it increases transmission feel.

(shrug)