bullionz

iTrader: (1)

I just installed the SPL bushings in the lower control arm (shock mount + inner), and compression rod, and the clunking noise is crazy loud. They have the white rubber rings...not sure what version that is.

It sounds like a piece of metal with about 1/4 inch of play slapping around over the smallest of bumps, and everything is tight, and centered. I bought the power grid swaybar endlinks (hotchkis swaybar with collars), and everything looks to be ok. It's only on the right side. Endlinks are adjusted exactly the same on both sides. Ugh...

Not looking forward to ripping apart the front end again. If I don't get any joy this weekend troubleshooting, I'm pressing them out it's that bad.

I expected some noise, but not banging loud.

edit" car is only dropped .6" (hotchkis springs & sway kit)

bullionz

iTrader: (1)

Ok so I got the car back on ramps this morning, and the noises are coming from the SPL bushings in the front control arms.

The compression rod bushings are fine.

When I flex the control arm by hand it makes a loud creaking noise as soon as the swaybar begins to apply tension.

For the install I used a 4 foot high with thick steel I-beams 12 ton shop press, and purchased all the sockets exactly as per the instructions, so the install went perfectly.

I think at the very least the shock mount bushing should be polyurethane in this setup in order help stabilize the movement of the control arm. Swapping the shock mount to polyurethane should also eliminate most, if not all, of the clunking.

When the poly bushings arrive, I might post up a quick video of how bad the creaking is. I thought it was the swaybar creaking up a storm, but I've installed them front and back on six different cars with no noise, so it was blowing my mind a bit.

Anyhow thumbs up on the compression rod bushings, looks like a big thumbs down on the SPL shock mount bushings at this time.

2fasst

iTrader: (6)

What are you talking about the 'SPL shock mount bushings'? Are you referring to the lower control arm bushings?

terrasmak

iTrader: (8)

Big thumbs up actually, they are just not a street quality part, its only noise. BTW when you mentioned earlier about adjusting your endlinks to be equal, YOU SCREWED UP. With the car on the ground, adjust them so there is ZERO preload on the swaybar. Unless your suspension us perfectly equal and your swaybar is perfectly straight, endlinks willnot be equal lenght.

JDMStanced

iTrader: (16)

i'm starting to feel that solid compression arm bushings are completely different than stock ones. Especially when driving over lane dots, i feel everything lol
The clunking noise that Bullionz described is noticeably minimized with the rubber rings that SPL provided.

Chi-TownWarrior

iTrader: (3)

Can anyone give me an idea of how loud the shock bushings are? I'm either going to get the SPL ones or the White lines. If the noise is just the ball joints like some people say, then I'm up for either the moonface RCAs or I may give the Megans a shot.

Thanks.

bullionz

iTrader: (1)

Yes the "outer" bushings on the control arm that the strut bolts to on the control arm. I'm 99% certain the insane level clunking I have is related to the control arm flopping around over very minor breaks in the road. It seems a lot worse on smaller frequent irregularities than larger bumps.

bullionz

iTrader: (1)

On both sides the bolts are within one or two degrees of being centered with the car on the ground.

I'll get under there and take another look, but I read over the instructions, and have done a more than a few swaybars before so everything looked nice and centered.

bullionz

iTrader: (1)

I should have the whitelines on within a couple weeks. They are on order. I'll post back the results.

I found the bushings on the control arm very creaky due to the movement of having both bushings on the CA articulating. The creaking has settled down in the past two days which is odd, but I did dial back the firmness one notch on the swaybar so not sure if that has anything to do with it. Odd. It sounded like an old rusty couch for two pretty much weeks straight.

IMO going poly with the outer CA (strut mount) bushing will help keep the control arm from twisting which, from what I can see, should prevent the CA's from banging around over the rough.

I'll know soon enough.

JasonZ-YA

iTrader: (60)

okay, terrasmak is right, his approach is off and people hate him cause he races, wah, wah........epstein and bullion have good info as well, but the fact is this:

Review the suspension 101 thread, but the 350z is an SLA suspension design...ILO using double wish bone (like the G37) the 350z has two lower control arms.........a Tension arm(transverse link) and a Compression arm.......

Tension arm/Translink:
There are two bushings in the tension arm (1 at the K-member(inner) and 1 at the coilover mount point(outter) ). Also note that the swaybar endlinks attach to the tension arm as well!

Compression arm:
There is only one bushing on the Compression arm - the large pin to under brace location, the opposite end is a tapered ball joint to steering knuckle.
Back to SLA suspension set up:

LOWERING THE Z and its affects on the lower arms:
The worse thing you can do is lower the car more than an inch…….when you lower the Z, the body drops, and the wheel tucks/the steering knuckle goes up? Same thing...


Compression arm:
The worse thing you can do is lower the car more than an inch…….when you lower the Z, the body drops, and the wheel tucks…….think about the mounting points of the compression arm, the pin side drops(car side), but the knuckle (ball joint) side goes up(wheel side)….

In turn, the compression arm at rest is now no longer "perpendicular" to the pin….its pitched upward and you immediately forgo some travel due to lowering….

This alone is one of the biggest reasons………..its not directly the SPL's bushings fault, it’s the "owner" and his "need" to lower his car……

Tension arm (translink):
Car lowered, Now, the tension arm is also pitching up! The car mounted side(K-member) is lower and the arm pitches upwards to the steering knuckle and is attached with a upward pointing ball joint that is mounted on the kmember itself. Unlike the compression arm, the tension arm mounts to the ball joint.

Doing this, (lowering the car) and adding bushings with out adjustable endlinks then creates a bind in the system………a limiting factor that pulls on the tension arm.


My suggestion:
I have mentioned this before, but the best front end set up is to have:

Compression arm:
SPL compression rod bushing in the compression rod chassis side - done.

Tension arm/translink:
SPL translink "INNER" bushing on the tension arm point at the k member.
Whiteline bushing at the outter, coilover to tension arm point. - why, little movement and small amount of articulation, no need for solid spl bushing here!

Now, if you think about that set up the points where the two front lower arms attach to the CHASSIS are solid and free moving/articulating arms………from there, pair this set up with SPL front upper control arms and the free moving front suspension will have all chassis mounted points as solid bushings free floating….

Any questions?



JDM, being that low your gonna have contact by design of the Z sla suspension, the spl bushings tapered cones will make contact with the compression arm edge……there is no fixing it for you if your that low……..ensure your ride height is correct at each fender….review my post 9 on my suspension 101 thread..




I will say this, as shown in my suspension 101 thread(post 23) I write """This dude had some made back in the day: ***'n baller!!! "" that link shows these bushings he had made (see the top left and top right bushings):


Notice how leeboyNY made these front compression arms at a local shop! Notice how they don’t use tapered cones for mounting.....no contact due to no tapered cone....more clearance at the very least over spl............

trust me guys, ive been dealing with compression arm bushings well before spl came out with their bushing....im a drifter and i have compression arm contact with the inner wheel rim at times.........ive hated it for the compression arm for years but "it is what it is"....

-J

JasonZ-YA

iTrader: (60)

yes, good idea! like i mention above..

-J

slmdchvy05

iTrader: (3)

I have been thinking about getting these for my car as well, great write up.

bullionz

iTrader: (1)

Totally agree, I remember briefly reading about going poly in the outer CA bushing but never put it together in my mind until I got under the car a few times to actually think about it.

Have a few bushings to go over in the back end, and already the car is feeling super tight. At some point over the next few months will do the subframe, and diff bushings.

The creaking noises in the front end have completely disappeared now, so I'm still scratching my head over that one. Wasn't the swaybar.

Hey thanks again for the trailer hitch btw. Quality piece.

Chi-TownWarrior

iTrader: (3)

For the people with the SPL rear bushing kit, it the shock bushing issue the same?

JasonZ-YA

iTrader: (60)

ya, its movement arc is small.....

the back end, the best you can do is solid diff bushings and then solid subframe bushings.....i have write up "how to's" on both...

the bushings in the rear knuckles are very small bushings....the factory bushings are completely find, except for the rear strut to knuckle bushing....

that one is recommend SOLID spl, thus as you can tell is the reason why places like IPP sell it separately on their site. see here: http://www.importpartspro.com/splrksz33.html


just practice a teflon or similar lubrication schedule/timeframe......my car has nearly every bushing replaced now.....i lube and rock and roll with no issues..

werd!

-J

terrasmak

iTrader: (8)

Not at all, the rear arm is mounted to the knuckle,

customworks

...

qxz9027mkii

iTrader: (2)

what i understood is the annoying clunking sound everybody is experiencing is a combination of:

1- having SPL Outer LCA bushing (shock mount)
2- lowering the car more than one inch

The Solution:

1- Installing the whiteline poly bushing instead of the SPL Outer LCA solid bushing.

fastintentions4

iTrader: (89)

I will toss in my knowledge. Local member cameover the other night for having an issue with his spl bushings..come to.find out that his set that he had didn't have the rubber o-rings in it like mine. There should be 4 o-rings included that go in between each compression rod. This prevents the noise....his were very loud Everytine we moved the ARM around

fastintentions4

iTrader: (89)

Agreed with Jason on this. The member i worked on lastnight had all spl bushings...a lot of noise which is known from going to a solid bushing.


I however run Whiteline inner lca, Whiteline shock mount and spl compression bushing....I don't have Any noise and im slammed.