Anyone knows if there is enough clearance to regrease as needed? I am planning to do the RB front bar and use greasable bushings but not sure about the clearance. I know some people use JB greasable bushings so I assume it should be ok but just want to confirm and save me some labor removing the wheel and check.
If you use rubber bushings this won't be an issue. A grease gun generates significant pressure, more than enough to force the grease into where you need it. Poly bushings that are greaseable sometimes have small channels to allow easier greasing too. Actually, you want the bushings tight, just enough to let the bar move. Any more than that and they will rattle and bump.
Edited to add-
Thought about this some more- did you mean is there access to the bushings to grease them as needed? In which case, the answer would be not much. It would make it a lot easier if you installed extension lines on the zerk points and mounted them at an easily accessible spot.
Also, if you just change out the oe bushings for poly, without the bar, how much improvement in body roll is it? Would it be equivalent to having a couple mm larger bar?
Depends on what you use for bushings, but it will feel a bit stiffer. It doesn't really change how the bar works though. The poly is far less compressible then the rubber, so its effectively taking up the slack and not allowing the bar to move as much.
Using poly bushings on just the bar won't be too bad for ride quality, its when you do everything that it goes downhill rapidly.
I have Koni/RB springs with Progressive rsb on stiff setting and am still not happy with the body roll. It's more like the initial roll that I am not happy about. The rear seems to follow nicely though. It's also feels like making the right turn is much flatter and more controllable than the left. Maybe driver's weight does help a bit.
Nothing wrong with a bit of body roll. It helps with the weight transfer and may provide a more predictable breakaway at the limit depending on what tires you have.
If left/right turns feel different, it may be something else other then the bar. Alignment maybe? If you dial out the rear toe to something like .08° on the rear that might help, and check the rear camber too. 1.5° or maybe a bit more seems to work well. Remember that toe and camber are not independent here, you may need adjustable arms to get it right.
The type of rear sway bar used on many MAZDA's do not require sway bar pre-loading, so perpendicular alignment to the center axle line is not necessary. But for safety of clearance concerns it should at least be checked.
This may be another reason for the difference in left/right feel. If the bar has a bit of preload, that's what can happen. When you install a bigger bar, you should use adjustable end links to prevent preload, especially when lowering the car any significant amount. The studs on the endlinks should pass through the hole in the bar freely on both sides without having to bend the bar to get them in.
The bar should be parallel to the chassis for optimum performance. The geometry doesn't work as well if it isn't.
Here is a graphic I found on the web a while back that shows how the position of the bar can affect the suspension geometry-
If its way off you can actually break stuff. See the center picture and the way the force is vectored? The bar is a simple torsion spring. You want the center part to rotate on its axis. The force applied needs to be perpendicular to the lever arm to do this. If it isn't it will pull on the bar instead of turning it and the bar will not be as effective.
This can also tear the mount off the chassis in extreme conditions with a big bar. :surprise:
Have you considered H&R or Vogtland springs? Both are similar progressive type springs that are stiffer than OEM. The H&Rs (# 28821) come in two slightly different specs. The -2 variant is slightly stiffer for diesel cars ( TUV approval says the wire diameter of the -2 version front springs is .5mm thicker and the coils are 2mm shorter, rears are identical), the -1 variant is for gasoline powered cars.
They do ride well, the car handles very well, they aren't too low for daily driving either.