redgs4

Had some work done on the GS last week. Replaced the TRD Blue sways with Daizen sways, replaced the control arms and tie rods, had the Daizen bushings installed, and had the car raised (HA's) by a couple of turns front & back. Way too much done to focus on any single item but had some observations to share.

First, the road noise that's transmitted into the cabin has shifted upward a half octave or so. Hard to describe, but used to be a deep thuds/thumps - now it's higher and reminds me of rain hitting a coffee can. I attribute this entirely to the change in bushings. Keeping things in perspective - I am running 20's, a full complement of Tom's braces, upgraded Daizen bushings and Tein HA's on full hard.

Second, after I upgraded to 20's I have had the usual rubbing and tire hitting the liner as I drove over bumps and railroad tracks. Car was sitting at about 1/2 finger height or less. I had the car raised to about 1 finger (an added 1/4" front, 1/2" back) and I now have zero problems. All the places I used to rub I am easily clearing (no more slowing down to a crawl to clear expansion joints and railroad tracks). Now that the rubbing is gone I'm hoping to dial back the HA's.

I'd love to tell everyone about the wonderful handling and how the chassis and steering have been tightened up, but it's been non-stop rain here in Norcal.


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RMMGS4

iTrader: (5)

Chris,
a couple things. Can you try softening up a little on the HA's and let us know if the noise level is affected? (Whenever it stops raining of course!)

Not only do you have a higher spring rate than most coilover users, but with the shock valving on full hard, I'm not surprised if you are getting these loud knocking sounds.

To point a finger to the bushings? Well no argument they are a likely contributor, but I don't think they are the root cause.

More than likely there are several contributors rather than one root cause.

Also, I know your tires are worn and we all know how many bad noises go away when we get new tires.

I'm hoping the tires and ultra stiff suspension are the two main causes of your troubles or let's say 70 - 80% of it.

redgs4

To clarify: I'm -not- saying there's any new noise. My observation is the same noises have been shifted higher in the audio spectrum. The tires and ultra stiff suspension tuning are undoubtedly the root cause of the noise but are unrelated to the change in character of the noise.

I'm sure dialing back the HA's and getting new (quieter) tires will help. Both are on the list.


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RMMGS4

iTrader: (5)

Ahh I C your point.

Same thing , only different.

Neo

iTrader: (3)

Congrats Chris. So you are finally all red underneath huh?

redgs4

Strangely enough, no. My Tom's 6-link is the special silver edition.

rominl

iTrader: (4)

very nice chris, congrats on the bushings!

pavster

I also just installed the daizen bushings, and it's definitely increased the noise inside the cabin. Things that didn't use to rattle suddenly started rattling on sharp bumps. Not very surprising if you compare the stock castor arm bushing (mostly air) with daizen (hard polyurethane).

-pavel.

ndallas_gs

What tires have nbeen found to be the quietest?

Kharizma

iTrader: (6)

have you had any problems with squeaking?

pavster

If they start to squeak, it will be a couple of years down the road. At least such was the case in my past experience with polyurethane bushings.

redgs4

No problems with squeaking but long term I would not be surprised.

As for tires, "quiet" is pretty low on my list. I'm currently looking at the Potenza RE050A Pole Position and the Yokohama Advan Sport. Both are max perf summer only tires which are supposed to have some consideration made for noise in the design.

LEXSOOS

I've installed my Daizen bushing kit just yesterday, that was DIY done at another members garage. Upper control arms are the easiest part as far as replacement, Caster Arms have been done at local shop since we did not have access to any press, Unfortunetly i was unable to replace bushings on lower control arms due to rusty bolts.

There is something else i want to bring up, diffrence betwen Brand new OEM parts and Daizen kit.

I have installed Brand New OEM upper control arms and Caster arms (october '05) now riding on Daizen, it is huge improvement in handling and the most i can notice, is how precise turns are, now i have feeling that rear can not keep up with front (handling)

Most difference makes Caster arm bushing (ride quality) not a problem for me, but i know some ppl complains because road noise is being transmitted into cabin.

One more thing, i belive that combination of Daizen upper control arms and lower control arms bushing with OEM caster arms could provide much better handling and ride quality for those who preffer litlle upgrade over All New OEM replacement.

- Jake

rominl

iTrader: (4)

wow very nice review, thanks for the input!

so you saying that you have driven a car with NEW oem control arms, and then you tried these daizen bushings, and you still think the bushings provide a much better handling response huh? that's very good to know!

LEXSOOS

Yes Rominl, there is big improvement betwen Daizen kit and OEM bushings, and i haven't installed lower control arm bushings yet.

There is something i'm concerned about, Upper control arm ''Daizen'' bushing inner sleve diameter is not matching OEM bolt size, in fact it is to big, causing movement which is not acceptable.

I would like to ask Todd "TM ENGINEERING" what is his expirience with it.

Maybe i just got wrong set for '01+, i'm not sure, mine is '00

Rominl, do you have an idea whats the diffrence betwen 98-00 and 01+ Daizen bushing kit?