eyecandy

iTrader: (19)

I would like to see what kind of interest there might be in a pillow ball and/or polyurethane bushing kit. Over the past few months I have been conversing with a number of the JDM companies that produce bushing kits, gathering as much information on the details and specification of the kits they offer.

While there are roughly 20 or so bushing kits available, not all of them suit the needs for you average RX7 owner, more on this later. Although depending on your interest and needs/wants I would be willing to try to setup a group buy for a polyurethane and/or pillow ball kit (more on this later), even try to include the possibility of giving you the opportunity to purchase a partial kit (ie bushings for the front upper/lower or rear end, trailing arms etc), although this maybe a stretch.

To make a long story short there are essentially 3 types of kits available

1. Polyurethane
2. Pillow ball (non-sealed/lubricated OR non-sealed with lubrication)
3. Pillow ball sealed and lubricated

Number 2 is not an ideal choice for street applications, due to the possible contamination from the environment prematurely wearing at the ball and race. This leaves numbers 1 and 3 as viable options.

The polyurethane kits are just about identical to the OEM bushings with the only difference being the durometer or shore rating. The two kits I speak of are the MazdaSpeed (for comparison only) and Autoexe. The Mazdaspeed urethane range in the 60-70 shore roughly retailing for $1500 for 22 bushings; while the Autoexe ranges in the 70-75 shore roughly retailing for $1000 for 22 bushings.

Here is a break down of the bushings in the kits:

-4x Front upper arm
-4x Front lower arm
-4x Front lower arm support
-4x Rear upper arm
-2x Rear lower arm
-2x Toe control (inner)
-2x Trailing arm

The benefits of a polyurethane kit:

-OEM style bushings (uses the same design for each bushing that Mazda used for production)
-Increased performance (Mazaspeed 40% stiffer, the Autoexe are stiffer yet)
-Highly street able
-Low road noise and vibration transfer
-Best choice for your tired OEM bushings while gaining performance
-Maintenance free

The Pillow ball (sealed and lubricated) is the next option. These are the ultimate in performance and roughly retail for $1150-1350 for an 18 piece set. They feature a hard chromed pillow ball with a dry-bearing lubrication (metal/alloy mesh of stainless/graphite and Teflon) protected by a dust and water proof seal. They say chassis mounting reinforcement is not required with the installation of the pillow ball bushings.

Here is the break down of the bushing in the kit:

-4x Front upper arm
-4x Front lower arm
-4x Rear upper arm
-2x Rear shock mount
-2x Toe control (inner)
-2x Trailing arm

Features:
-Precision machined and developed for OEM suspensions
-Dry-bearing (metal/alloy mesh of stainless/graphite and Teflon)
-Ensures tight tolerances
-High load bearing
-Good corrosion resistance
-Long life (good abrasion resistance, the demo car has been equipped for 4 years and they are still in excellent condition, under both street and track use)
-Dust and water proof seals
-Maintenance free

Here are a few comparisons on coefficient of friction of pillow ***** w/remarks:
-PTFE liner 0.31*
-liner begins to creep due to high face pressure

-Grease/oil lubricated 0.38*
-oil film becomes inadequate

-Dry-Bearing 0.11*
-retains smooth wear and longevity

* approximate values

I believe that is about it I am terribly sorry for the long read, I am just providing you with all the proper information, if anything else comes to mind I will inform all of you. Depending on the interest in the Autoexe or Pillow Ball kits I would be willing to see what kind of price we could get, the problem is the Japanese do not like to conduct “group buys” (I think they do not grasp the concept) and like to see hard evidence before and commitment. Please let me hear your feedback. If you have any questions please feel free to ask and I will do my best to answer them.

Here are a few pics of the kits.

M104-AMG

iTrader: (8)

How much are the Autoexe diff bushings that are slightly harder than the Mazdaspeed ones ?

:-) neil

eyecandy

iTrader: (19)

I would have to get back to you on the Diff mounts, I think they are about $180 for the set and they are 75 duro, the Mazdaspeed I think are over $200 and 70 duro.

jasonlel

Are those rear lower arm Polyurethane bushes with pillow ball? I reckon the OEM rear lower arm bushes are with pillow ball. Please advice...

eyecandy

iTrader: (19)

Yes that is correct.

jasonlel

What do you think if the rear lower arm are fitted without pillow ball, just with Polyurethane. Anyone tried before? Will it affect the handling?

eyecandy

iTrader: (19)

The inner lower bushing needs to be a pillow ball, for stabilty under load and to ward against bind. Read this thread and it may help you understand alittle better https://www.rx7club.com/3rd-generation-specific-1993-2002-16/bushings-pillowballs-balljoints-diagram-480142/ (particularly Howards and my post towards the middle and end for the first page)

This is why your only option for this location is oem, MazdaSpeed, Autoexe or Spherical bearing. Essentially if you were to look at how the above bushings are designed, they are similar to a spherical bearing (rather than all metal they are suspended in rubber, or a hybrid of rubber and spherical bearing) with Jimlabs and the Delrin bushings you are loosing the design trait.