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I was wondering why my rear wheel is not straight..... Does the rear suspension have adjustment for the rear wheel? The front of the wheel(closest to the driver side door) is angled inward.
Only bushings in rear are upper a-arm inner sliding bushings and lower shock mount on the same upper arm plus the front of the trailing arm where it attaches to the unibody.
The rest of the "bushings" are rubber isolated spherical bearings and non isolated spherical bearings because the FD rear suspension pivot points are all multi- axis.
Putting single axis pivoting poly bushings in place of multi axis spherical bearings makes the rear suspension bind and squeek.
Eliminating the sliding bushings in the rear upper arm is fine, but eliminates the passive rear toe steering to make the car more forgiving to bad driver inputs. Changing those is kind of a race car thing.
Only bushings in rear are upper a-arm inner sliding bushings and lower shock mount on the same upper arm plus the front of the trailing arm where it attaches to the unibody.
The rest of the "bushings" are rubber isolated spherical bearings and non isolated spherical bearings because the FD rear suspension pivot points are all multi- axis.
Putting single axis pivoting poly bushings in place of multi axis spherical bearings makes the rear suspension bind and squeek.
Eliminating the sliding bushings in the rear upper arm is fine, but eliminates the passive rear toe steering to make the car more forgiving to bad driver inputs. Changing those is kind of a race car thing.
Welcome to FD RX-7. Its a race car.
Can you elaborate on what you said "Putting single axis pivoting poly bushings in place of multi axis spherical bearings makes the rear suspension bind and squeek."
I'm about to order a bushing kit from J-Auto.
My 2 cents is get under there and take a look at the FD suspension.
Its mainly the rear toe links rubber isolated spherical bearings that should never be replaced with poly bushings.
Juan at J-Auto can guide you through this rear bushing binding/squeeking issue with poly bushings- he should be very familiar with FD suspension.
I bought my FD bushings through Juan @ J-Auto. Very good business that supports FD community.
Let him know what the FD means to you and what you assess its value at and he will tell your cost options.
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I bought poly bushings from J-Auto to replace the 8 bushed pivot points up front (4 sliding "toe" bushings in lower arm- 4 regular bushings in upper arm).
And the 6 bushed pivot points in the rear (2 trailing arm, 4 upper arm sliding "toe" bushings.)
I wanted to eliminate front and rear passive toe steering/stability control for racing .
The FD was built before Mazda implemented electronic dynamic stability control in the RX-8. They used mechanical dynamic stability.
The Yamaguchi FD RX-7 development book covers this well.
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Single axis pivot means it operates in a single plane, like an FD car door hinge.
Multi axis pivot means it operates in more than one plane, like an FD 5 speed shift lever.
How do you know if your arm bushings are is good shape beside seeing the obvious cracks torn etc bushings.
I jumped the gun and started removing the suspension parts plus I already ordered the aftermarket bushings. Am I waiting my hard earn money prematurely??
Yes, you need to slow your roll and learn the particulars of the FD before you damage it .
Get a factory workshop manual or copy thereof read the relevant parts before working on the car as well as following along while working on the car.
I could only tell my bushings went bad from the change in driving feel between when they were good and then failed.
This is because the stock sliding bushings have some deflection front to rear under a pry bar normally, so its hard to spot good versus failing bushing.
Its likely my bushings where issued their death sentence when my coilovers were installed.
The installing party did not have the car on ground or jack under the tire to place the suspension arms at a neutral or normal travel before tightening the nuts/bolts.
Having the suspension loaded before tightening allows half the bushing rotation in suspension droop and half in suspension compression.
If you make the mistake of tightening the bushing nuts/bolts at full suspension droop you have bushings rotated half way at rest and twice as far a rotation in compression and the bushings center tears away from the outside.
Some background history is needed... I've had the car since 1995. It sat mostly over the years because it was either being worked on or life took precedent.
So after 15 years of the car being down, as an adult I have the funds to get it back on the road. Primarily for my son and I to enjoy.
Two months ago I finally brought the car home from the shop which now after not driving it for 15 years I start to realize it's age.... The little that I drive it now I'm noticing clunking sounds in the suspension and steering. Even though the body has relatively low mileage (around 56k) certain area naturally show deterioration.
With the addition of the PS leaking and the noise I felt it merits tearing out the components to bring some new life into this car. With having to drop the sub frame in order to remove the rack, I figured I'd remove the arms etc. Also have new Flex Z coilovers to install as well. So instead of doing all this in stages it would make sense to rip out all out at the same time.
@cr-rex this why I didn't wake the car to get aligned first.
Now upon removing the arms I see that visually the bushings appear to be in good condition but still might be worn internally. So do I take a chance and reinstall everything with new coilovers or swap out the bushings. Even if the oem's last another few years is it worth waiting?? I don't know about you but it's back breaking for me and I'm not getting any younger plus I can't trust a shop to perform the work.
@BLUE TII can you elaborate what your referring to when you mention "half the bushing rotation"
Also when tighten do I lower the wheels to the ground but not fully? Then lower fully and torque?
Thanks!
"Having the suspension loaded before tightening allows half the bushing rotation in suspension droop and half in suspension compression. If you make the mistake of tightening the bushing nuts/bolts at full suspension droop you have bushings rotated half way at rest and twice as far a rotation in compression and the bushings center tears away from the outside."
In a pressed in steel to rubber bonded bushing the rubber flexes radially as the bushing rotates axially.
In simple terms, there is no rotation of any component within another component once tightened down, the rubber just flexes.
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The aftermarket poly bushings are different.
Those have the steel center piece that will be clamped into the subframe when tightened unbonded and free to rotate within the poly bushing section that is pressed into the suspension component.
if you are building an enthusiast or track car you want to torque everything in the suspension to the high value/upper limit.
and you want to do that with the car on the ground, or "ground"
you want to torque everything in the suspension to the high value/upper limit.
and you want to do that with the car on the ground, or "ground"
Yep.
Here's a test you can do yourself at home since your suspension is apart. Attach the rear upper control arm and place it in some extreme position like all the way down or up. Tighten and torque the bolts to the unibody to spec. Try to move the arm. Watch the bushing material flex.
This is why you want to tighten and torque the fasteners when the full weight of the car is on the wheels in the way it would be driving down the road.
Now, practically speaking, tightening those bolts on the "ground" will be near impossible. So you need to mimic that. You can stack some wood 4x4 under the control arms and lower the car onto them without the wheels for example. Then tighten and torque to spec.
Regarding bushings - I'm not a fan of the aftermarket suspensions bushings that I have tried for a street car. Great for autox and track imo but didn't like it on the street. Too harsh. I eventually wound up replacing poly with the harder rubber Mazda Competition bushings. YMMV. At this point, I suppose it can't hurt to replace them while they are still available. The car isn't getting any younger.
Some people purchase newer used JDM suspension arms or the newly available Dorman aftermarket arms for fresh ball joints and bushings without having to press them out and in.
I have no experience with either, but
I do have experience putting in new bushings and pillow ***** and it is a big expensive job on the FD.
Has anyone used these before? It's crazy how cheap these are. I'm considering these because the ball joint on my A arms are questionable. They are not flopping down but can still be moved around by hand.
