ATC529R

So I'm working on shocks and have the strut rod removed from the control arm.......just curious if there is a general rule as to adjusting this.

I.e. I was thinking 90 degree angle from the end the spindle to the frame.


just curious if anyone has any recommendations as to adjust it a little further back, which might seem to toe out the tires or more forward which might toe them in.

I know you can make up for it with tie rods/alignment, but curious as to others recomendations and any effects on handling. 90 degrees would seem logical.

thoughts?

GSLSEforme

For removing strut rod for maintenance /repair work,it's recommended to leave innermost nut in place so strut rod can be returned to original position. It is not an adjustable alignment point per se. Look closely at strut mount and you will see it is offset and can be installed in 4 positions to allow adjustment of caster/camber. Optimum position to install strut mount is facing in toward engine and back toward firewall. This will give you max negative camber and max positive caster. Do the same for both sides. The adjustment here is @.5 degree. You will likely end up with 0-.25-.50 negative camber. These cars can use more negative camber,you can go up to 1.0 degree negative camber before tire wear is a factor. Negative camber increases turn in and cornering power. To get more negative camber will require going to camber plates.

Increased positive caster improves steering wheel return to center after a turn and improves high speed stability/tracking. The strut rods can be used to dial in a bit more caster to increase these traits,however the more positive caster dialed in,the heavier the steering feels particularly at slow speeds where increased turning effort is required. I imagine your steering effort is high as is with weight of engine in car. The only real way to adjust caster by adjusting strut rods is on an alignment rack to see the adjustments as they're being made.

Pics of strut mounts adjusted for max negative caster and max positive caster. This adjustment netted me 1/2 degree on driver side and 3/4 degree negative camber on passenger side-on my car. No two cars are same. Do the adjustment when reinstalling struts and look at readout when aligned to see what you have

rxtasy3

iTrader: (2)

i think he's talking about the rod that connects to the LCA, keeping the front wheel located front to back of the fender well.

ATC529R

yes

Freeskier7791

either center the tire in the wheel well or go for maximum caster. I really like the feel of caster in this car makes the steering snappy, but if you do not have power steering it will be a bear in a parking lot, 5 deg of caster is a good target

LongDuck

Whatever you do, be sure to tighten the front bushing, washer, lock-nut and castle-nut (*+Cotter pin) to spec. I replaced mine with polymer bushings years ago and thought I had them tight enough. The DS nut came loose over time and gradually loosened by about 1/2" - it was enough that when I jammed on the brakes, the car would dart to the left and try to slam into the median, requiring considerable steering effort to keep it braking in a straight line. Under heavy braking, the DS rod would allow the left front wheel & tire to slide back a bit, creating toe out on that side and pulling the car in that direction. Under power and in a straight line, it felt and drove just fine.

Thinking it was brake caliper related or something else, it took me awhile to finally look at the front control rods to see the problem. Tightening the front nut back into position made it right again, and I made sure to give them both a good tightening on both sides to maintain caster setting.

I prefer to center the wheel & tire in the wheel opening using the control rod distance, which is visually appealing, but recognize that Mazda FSM has the distances to set based on measurement from the thread start to the center of the mount plate on the frame. This helps ensure you get the right positioning, but then torque applied to the 2 nuts determines how much flexibility that joint will have. Very little flexibility will give the best cornering performance and road feel, but the bushings need some room to work (rotate),

GSLSEforme

Yes,we're all on the same page...in a nutshell,when removing strut rod for repairs to components it attaches to(lower control arm)care should be taken that inner nut(backside of front mounting bracket)remains in same position as before strut rod was removed so it can be reinstalled as before. No need to move that adjustment to remove strut rod,only the nut/washer on front side of bracket.

Regarding op wondering about adjusting them further back...Toe adjustments are done with tie rods. Adjusting strut rod further back will decrease the caster and affect the handling...negatively. Read my prior thread about increasing positive caster and why and you can understand what happens when you do the opposite. There's no reason to change position of strut rods any different than how they were encountered when removing them,key is to not move rearward nut. When you start adjusting them one way or another,you're upsetting the original caster spec designed into suspension. You will not be able to return them exactly to their prior position,best you can do is count threads. They should be left as is.
The adjustments i'm referring to,to increase positive caster,to enhance traits mentioned in my above post can only be done on an alignment rack so you can see what you're starting with AFTER orienting strut mounts as per previous post,so you know what that spec is-to adjust from that point. Again no two cars are same and adding x amount of caster to another car because it worked well on a previous one,won't yield the same results. When i speak of using strut rod dimension for INCREASING positive caster,these are slight adjustments to equalize and fine tune caster to change steering response. This is a subjective feel and my personal preference,i want my car to track well/hold a line at speed with no hands on the wheel-no wandering. This is experimental in that,you change the adjustment maybe .5 degree and roadtest,back on rack and more adjusting til a point is reached there's no further benefit and you may back off the adjustment a certain amount.Could be 1.5 degrees or more.
You need to know exactly where you are when adjusting to keep cross caster correct. I do my own alignments and to do what i just described took me @ 3 hours start to finish on a very early Sunday morning to test drive and on rack 4 times before satisfied with results.

I will add there's not much point in pursuing caster fine tuning such as this if rubber bushings,in good shape or not are still in place,imo,too much deflection. .5 degree caster change with poly strut and inner control arm bushings can be felt,rubber,not so much and adjustments can't be exact due to deflection. It should be said,ball joints,pitman and idler arms and tie rod linkages should have 0 play and steering gearbox properly adjusted to yield best results.

GSLSEforme

LongDuck,am surprised with amount the locknut backed off you didn't notice any other quirks besides under braking. The torque specs for strut rod nuts is reached when the washers and internal sleeve are bottomed against rear nut. The flexibility is determined by the material the bushings are made of.