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Old 12-26-2013, 03:59 PM   #1
Pete_89T2
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Default Suspension Bushings Selection Discussion

Since I still have all the stock suspension bushings in my S5 T2, and they are all starting to show the usual signs of age/wear (i.e., drying/cracking), I plan to replace them all this winter.

For background on my setup, I replaced all the springs with Racing Beat springs for the T2 and replaced the struts with the adjustable KYB AGX units. This was back in 2006, and the bushings all looked good at that time. I’m still running the stock tire size on stock wheels, along with the stock sway bars/end links.

I'm happy with the way the car handles and with its ride comfort quality, and I don't want to compromise either with my new bushing selections, so my objective is to retain that. I also don't want to increase NVH characteristics or decrease durability - since bushings are generally a PITA to replace, I don't want to have to do it again in a few short years.

One other thing, which I think has to do with the DTSS rear steer bushings is that when I push my car to 9.5/10's of its limit, I’ve noticed the rear end feels a bit squirrely to me when the DTSS starts to take over - my guess is those bushings are shot and need to be replaced too. Not sure if I want to do away with the DTSS functionality or try to retain it the way it was designed in, as I’ve never driven an FC with a known “working” DTSS to form any opinion on it.

From my market research, seems that the bushing options for everything except the DTSS bushings are: (a) Stock Mazda/OEM bushings; (b) Slightly stiffer Mazdaspeed stock bushings (still rubber); and (c) & (d) polyurethane bushings from either Energy Suspension or Prothane. Of the (c) & (d) options, I think the Energy Suspension (c) bushings are marginally better simply because they are impregnated with graphite, which should help keep them a little quieter and durable over time. Both brands are available “ala carte” or as complete kits that cost about the same and replace all stock bushings except for the DTSS bushings.

As for the DTSS bushings, I think the only replacement option is to buy the Delrin DTSS eliminator bushings that Racing Beat or Mazdatrix sells. As far as I know, Mazda doesn’t sell the stock DTSS bushings separate from the rear carrier assembly – can anyone confirm if this is still true?

Next question – Would it make any sense to mix & match stock Mazda, Mazdaspeed and Polyurethane bushings? i.e., a mix of (a), (b) and (c/d) parts to fine tune what I’m trying to achieve here? My gut feeling (disclaimer - not based on any real suspension tuning expertise) is to go with the polyurethane parts for the sway bar bushings, but use stock or stiffer Mazdaspeed rubber bushings for the front & rear control arms. If stock DTSS bushings can’t be had ala carte, then I suppose only viable option there is to go with the RB DTSS eliminator bushing (delrin)

Thoughts & recommendations?






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Old 12-26-2013, 05:33 PM   #2
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Strictly suspension, go with the Energy Suspension kit, especially if you're running stock (i.e. anti-sway bars) components.

The Mazdaspeed (old Mazda Comp) stuff is pricey, if you compare per unit.
(I do recommend the Mazdaspeed stuff when talking about engine / trans mounts, front-nose rear diff, and top-rear rear diff bushings - none of these are "suspension" components though.)

I do recommend the DTSS eliminator bushings, as they do make the rear end more stable and predictable.
If you're used to the original DTSS, this mod will cause the rear to "feel slow"; it takes some getting used to, but in the long run the chassis is more stable.
Mazda used to sell an OEM replacement, but I'm not sure if this is still available or if it's "NLA" listed now...


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Old 12-26-2013, 06:39 PM   #3
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Agree with Ted on all accounts.... get the energy suspension kit and go to war.... and there will be some battles on some of the bushings as described below.

As Ted said, per unit, it comes out ALOT cheaper to get the ES kit as opposed to getting the MS pieces separately. IMHO the ES pieces are tougher and cheaper without adversely effecting the NVH.

No... when it comes to mounts, unless you want to take the BDC approach and purchase a 2x4 to cut into engine mounts, the MS stuff is the way to go... and again agreeing with Ted here, Engine mounts, tranny mounts, front diff nose mounts, and outside diff mounts are better had with MazdaSpeed pieces as opposed to the derlin counter parts. Having said that I do have a pair of derlin on the outside of the Diff because they were basically free and I really don't mind them. I didn't expect them to really increase NVH and they really didn't.

Installations.... first.... make good friends with someone with a press and a bearing separator or find a machine shop that has these two tools. Otherwise it's going to be a war of cutoff wheels, hacksaws, chizels and hammers to get the bushings off the pivot on the lower control arm.. The proper tools turns this into a 3 minute one handed operation and honestly, it would be worth the $120 from HF for the press and whatever they have a bearing separator for.

The press is also going to be VERY handy for all the other bushings... otherwise they're ALL going to fight in one way shape or form....

You also have an S5. I would look into finding a set of S4 LCA's, ball joints and sway bar links as well....
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Old 12-26-2013, 09:29 PM   #4
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Quote:
Originally Posted by TitaniumTT View Post
Agree with Ted on all accounts.... get the energy suspension kit and go to war.... and there will be some battles on some of the bushings as described below.

As Ted said, per unit, it comes out ALOT cheaper to get the ES kit as opposed to getting the MS pieces separately. IMHO the ES pieces are tougher and cheaper without adversely effecting the NVH.

No... when it comes to mounts, unless you want to take the BDC approach and purchase a 2x4 to cut into engine mounts, the MS stuff is the way to go... and again agreeing with Ted here, Engine mounts, tranny mounts, front diff nose mounts, and outside diff mounts are better had with MazdaSpeed pieces as opposed to the derlin counter parts. Having said that I do have a pair of derlin on the outside of the Diff because they were basically free and I really don't mind them. I didn't expect them to really increase NVH and they really didn't.

Installations.... first.... make good friends with someone with a press and a bearing separator or find a machine shop that has these two tools. Otherwise it's going to be a war of cutoff wheels, hacksaws, chizels and hammers to get the bushings off the pivot on the lower control arm.. The proper tools turns this into a 3 minute one handed operation and honestly, it would be worth the $120 from HF for the press and whatever they have a bearing separator for.

The press is also going to be VERY handy for all the other bushings... otherwise they're ALL going to fight in one way shape or form....

You also have an S5. I would look into finding a set of S4 LCA's, ball joints and sway bar links as well....
An air hammer to knock out the stock bushing is your best friend when installing the rear bushings.
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Old 12-26-2013, 10:15 PM   #5
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Yup.... Or a ball peen and a cold chisel... I'm referring to the rear bushing on the front LCA though.... Press and bearing separator...
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Old 12-27-2013, 07:16 AM   #6
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Thanks guys, lots of good recommendations & how-to info here!

Quote:
Originally Posted by RETed View Post
Strictly suspension, go with the Energy Suspension kit, especially if you're running stock (i.e. anti-sway bars) components.

The Mazdaspeed (old Mazda Comp) stuff is pricey, if you compare per unit.
(I do recommend the Mazdaspeed stuff when talking about engine / trans mounts, front-nose rear diff, and top-rear rear diff bushings - none of these are "suspension" components though.)
Yup, I do realize the cost of the Mazdaspeed parts are pricey as hell compared to the ES kit. The reason I asked about mixing & matching between MS parts and the polyurethane ES bushings is because in theory, the much harder/stiffer ES bushings dampen less that the stock pieces and might allow more NVH into the cabin. If you guys are saying the before & after difference regarding NVH is unnoticeable, then it would appear the ES kit is the no-brainer choice.

I'm only talking suspension bushings here; no plans to BDC my car with hockey puck motor mounts For those parts I've already decided to go with the MS parts. I already have the MS engine mounts, need to get the trans mount, front diff & rear diff bushings. May as well, since I'll be in there anyway!

Quote:
Originally Posted by RETed View Post
I do recommend the DTSS eliminator bushings, as they do make the rear end more stable and predictable.
If you're used to the original DTSS, this mod will cause the rear to "feel slow"; it takes some getting used to, but in the long run the chassis is more stable.
Mazda used to sell an OEM replacement, but I'm not sure if this is still available or if it's "NLA" listed now...
I'll have to give Ray Crowe a call and see if the stock DTSS bushings can be had separately and what they cost and let you all know. My guess is if they are, they will cost a bundle. In concept, a working DTSS sounds like a great idea, but since I've never driven an FC with a working DTSS, I'm inclined to just go with the DTSS eliminator bushings and be done with it.

Quote:
Originally Posted by TitaniumTT View Post
Agree with Ted on all accounts.... get the energy suspension kit and go to war.... and there will be some battles on some of the bushings as described below.

As Ted said, per unit, it comes out ALOT cheaper to get the ES kit as opposed to getting the MS pieces separately. IMHO the ES pieces are tougher and cheaper without adversely effecting the NVH.
That's what I needed to hear regarding NVH differences. Have you been running the ES pieces on your FC? How are they holding up over time?

Quote:
Originally Posted by TitaniumTT View Post
No... when it comes to mounts, unless you want to take the BDC approach and purchase a 2x4 to cut into engine mounts, the MS stuff is the way to go... and again agreeing with Ted here, Engine mounts, tranny mounts, front diff nose mounts, and outside diff mounts are better had with MazdaSpeed pieces as opposed to the derlin counter parts. Having said that I do have a pair of derlin on the outside of the Diff because they were basically free and I really don't mind them. I didn't expect them to really increase NVH and they really didn't.
Roger all that, no desires to BDC my car

Quote:
Originally Posted by TitaniumTT View Post
Installations.... first.... make good friends with someone with a press and a bearing separator or find a machine shop that has these two tools. Otherwise it's going to be a war of cutoff wheels, hacksaws, chizels and hammers to get the bushings off the pivot on the lower control arm.. The proper tools turns this into a 3 minute one handed operation and honestly, it would be worth the $120 from HF for the press and whatever they have a bearing separator for.

The press is also going to be VERY handy for all the other bushings... otherwise they're ALL going to fight in one way shape or form....
Realize this one is a major PITA... For doing the work, I can either do it all at the auto shop on APG where I work, where I'd have access to a press, bearing separators and an arsenal of air tools. To save myself some coin on the bay rental & car storage fees, I can yank the LCAs & rear hub/control arm pieces at home and take them to APG to use their tools to press out & install the new bushings. Or if Speed1 can do the whole job in a single day, I might just take the trip up there to let them do it all and be done with it.

Quote:
Originally Posted by TitaniumTT View Post
You also have an S5. I would look into finding a set of S4 LCA's, ball joints and sway bar links as well....
Good idea, that would make the ball joints on the LCA and sway bar end links serviceable. Are there any downsides to this, besides finding a good set of S4 LCA's? Does this alter suspension geometry at all and require some alignment tweaks?
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Old 12-27-2013, 10:59 AM   #7
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Hockey puck motor mounts would be over bdcs head 2x4 is where it at with him

I've been running the ES bushings foooooorrrrr.......16 years now I think? They all seem to be holding up pretty damn well given the type of miles that I put on the car. The MS pieces.... Not so well. Replaced the engine mounts a few times (mainly because the banzai cosmo motor mount adapters were not designed properly and the mounts were never loaded properly.) Once I built my own adapters the mounts seem to be holding up pretty well, they're actually strait now however they're still going to be need to be replaced but not with the same frequency as stock pieces. Even the front diff mount failed once on me.

Dave... Or in reality Kyle will be the one doing the work most likely... I would think it could be done in a day, I would check with Dave first though.

Using the serviceable S4 pieces doesn't change any of the geometry at all. You'll need a set of LCA's, a set of ball joints, a pair of the sway bar link brackets, and of course the end links as well. Last time I was there he had 2 Parts car FC's....
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2015 Audi S4 - Samantha - Zero Brap S4
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2000 Jeep Cherokee Sport - Wifey mobile - Now with 2.5" OME lift and 30" BFG AT KO's! So it begins
1998 Jeep Cherokee - 5 spd, 4" lift, 33" BFG's - Rotary Tow Vehicle
1988 'Vert - In progress
1988 FC Coupe - Gretchen -The attention whore BEAST!


I'm a sick individual, what's wrong with you?
I'm pure Evil
I'm still insane, in the best possible way.
I think Brian's idea of romance is using lube.
Your rage caused the meteor strike in Russia. The Antichrist would be proud of his minion.
You win with your thread. Most everything
It's a truck with a steel gate on the back. Just a statement of fact

Motec M820, AIM dash, ported 13B-RE Cosmo, 6-spd trans, 4.3 Torsen, custom twin wg fully divided mani, Custom 4" split into 2x 3" exhaust, Custom HMIC, Custom custom custom custom I like to welder stuff....
No Bolt-ons allowed. Dyno'ed @ Speed1 Tuned by me - 405rwhp on WG.... WM50 cuming soon.
-Angry Motherf*cker Mode ENGAGED-

Last edited by TitaniumTT; 12-27-2013 at 11:02 AM..
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Old 12-27-2013, 12:22 PM   #8
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Quote:
Originally Posted by Pete_89T2 View Post
Yup, I do realize the cost of the Mazdaspeed parts are pricey as hell compared to the ES kit. The reason I asked about mixing & matching between MS parts and the polyurethane ES bushings is because in theory, the much harder/stiffer ES bushings dampen less that the stock pieces and might allow more NVH into the cabin. If you guys are saying the before & after difference regarding NVH is unnoticeable, then it would appear the ES kit is the no-brainer choice.
The polyurethane bushings in the suspension points add very little NVH.
In fact, unless you're really looking for it, I doubt you could tell the difference between identical chassis' with identical mods with the exception of the suspension bushing differences.
In terms of STIFFENING the suspension, now most people would realize that there is something different!

If you have any type of upgraded suspension components (as most of us do), I doubt you would feel the difference; most would just chalk it up to the other upgrade suspension stuffs.

Even going from the stock 205 / 55 / 16 size tire down to a 45-series or 40-series tire is going to jar your spine more.
Energy Suspension does very good R&D on their products, so their product claims are spot on.
Man, I'm starting to sound like a commercial...
(Apologies, as I do not get paid to type all of this.)


Quote:
That's what I needed to hear regarding NVH differences. Have you been running the ES pieces on your FC? How are they holding up over time?
The enemies of polyurethane are heat and UV.
Heat is negligible, and UV is non-existent.


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