Good post. But since the main thing about "feathering" that everone does not like is the sound it produces once its worn improperly. So getting a camber kit would allow your tires to wear properly correct, hence you wouldnt get that annoying super swamper tire roar when u come to a stop.

 

O ya, and do G35s have this problem at all, im thinking about maybe sellin my Z and getting a G.

 

Ok so far.

For excesive even wear due to extreme camber, yes. For the "feathering issue, no. Cars with camber kits and perfect camber still get feathered.

Yes you would. The camber kit will NOT avoid that. I have camber kits front and back. And my tires still get feathered.

 

i didnt read the whole thread but id like to add my .02c. i have believed this from the get-go since i have a good understanding of toe, camber & caster settings from numerous other vehicles...i believe the feathering is due to a combination of the aggressive factory alignment specs (all 3 settings). the camber setting is what keeps the feathering in a particular location on the tire tread(mostly inside), the toe is what starts the feathering since its not perfectly "0" (pushes force agianst the inside of the tire), and the caster aggrivates the feathering issue since it is such an aggressive caster setting. the more (+) caster you have the more the tire is pushed forward out from the center of the suspension area, this applied with agressive (+) toe create a problem & the problem gets pronounced when braking as the weight of the car is distributed forward on to the contact patch of the front tires, wich is pushed out by 1- the agressive toe, 2- the aggressive cater 3- the aggressive camber!! i believe this but i cant prove it........take it as you want, prove me wrong, please! give me caster adjustemnt & i bet i can come up with a spec allowance for you that could eliminate feathering!....nuff said, what do i know?

-justin

 

Justin, I actually agree with you. I never studied what the spec values do to the car. My objective has always been to get the car within the specs that Nissan provides. It seems thatm given an OEM car and if you go by Nissan specs, you have the conditions necesary (as you state) to create feathering.

Of course, added camber (due to a drop lets say), toe and or caster will make bad things worse.

My goal with the camber arms, toe cams, and all that is to get back to spec per Nissan's design. I will then expect them to fix the design if the design and specs they gave me are bad. They say Toe is it, I go and adjust my toe.

In the process of reading about this for over 2 years you learn quite a few things. I have heard we do NOT need toe. That toe should be zero or as close to zero as possible. I have heard we barely need camber either. I personaly would go with camber -1, toe 0 in all corners. But this is just "web" learned and I am not really a professional at these things.

 

Slaponte, how long shouold 1 expect their tires to last if their runnin say 19s with stock suspension, usually freathering around 13k, and then if they change the suspension to what your running? How many more miles would u predict before the noise starts? Thanx

 

I had the feathering, bought my car with 10k miles on it and noticed it about 2000 miles later, waited till 30k miles till i tried to get the feathering fixed. They did do a fix on the front end (whatever that is?) and replaced the tires, however b/c i had 30k miles on the car they wouldn't pay for the tires even though they were new when i bought the car with 10k miles. So long story short i ended up eating the tire bill and was so pissed i almost sold the car. I have put 7k miles on the car however, and haven't had a single problem with tire feathering. I'm convinced they actually corrected the problem. Has anyone else had the problem go away after nissan did the fix under the tsb?

 

Sorry, I don't have a clue Mr. B!

If you have stock suspension you don't need to switch to what I got. All you have to do is find a good shop that will get your front toe as close to 0.2 degrees as possible, or shoot for as close to zero as possible, and hope for the best. You already switched to 19s, probably not RE040s so the thread pattern issue does not apply...

Back to the begining. My first issue was the "bunny hop" the car did down stright city streets It really pissed me off. So I went to Eibachs to correct this and get the 1" drop. That drove me to camber arms... None of the changes had to do with feathering.

For feathering Nissan says : adjust your TOE. thats it.

 

hm thanks slaponte, i've read so many posts and many sites about the feathering issue, but nothing I saw was the actual cause of the feathering itself, but I saw the camber issue brought up numerous times and just assumed (alright Im guilty, I don't read through them all the way :P) But thanks for the info

 

I think it gets mixed in because people drop the car, end up with extra camber, it can't be adjusted, and then the tires wear on the inside and everybody blames the camber. This is not feathering and the wear is very different. Now, the extra camber might not help matters, but people with perfect camber get feathered also...

Toe. Set Total Toe-in between 0 and 0.2 degree (2mm) which is almost zero. To hit the 0.2 each side should have 0.1, to hit the zero set each side to zero (easier me thinks). Don't let the alignment shop do it "green light vs red light", do it meassured. You should have NO toe-out.

 

id like to add more input if i may. some of these things ive stated in a previous response, but will add more to my reply: i believe the feathering is a result of all the aggressive alignment settings. the more aggressive you have the settings the worse the feathering & wear will be. -camber with heavy toe out on top of aggressive + caster is going to result in feathering. its my belief that the feathering happens while cornering & braking only, not in regular striaght line driving. i believe that getting toe to "0"(already mentioned), getting camber closer to the top of spec <closer to "0">(already mentioned) as well as leaning out the aggressive caster greatly(closer to +4-+5) then the feathering would disappear. as a result the car would not handle as well at all. honestly you need to ask yourself, what is most important? handling or tire wear? its hard to get an inbetween. as most of you noticed, as you were chnging the alignment specs per nissans TSB's, the handling has changed quite drastically. turn in just isnt so impressive anymore, almost a "loose" feeling..........what you want from your z will tell you where you need to set your alignment. i personally shot for an inbetween setting to slow the inner tire wear & feathering while retaining some handling. i chose this because i do not track my car, only occasionaly drive agressively on the street. replacing my $800+ 19" toyos often isnt as favorable as loosing some of the handling........just to end this, i believe some real improvement could be had with some adjustable caster ( on top of more camber/toe adjustment over factory as is avail), if it ever becomes available to the aftermarket! best of luck.......take my opinions as you will, thats all they are untill caster, camber & toe can all be adjusted together outside of factory capability!

-justin

 

I understand that camber isn't adjustable up front and toe is very limited. How about caster adjustment? How do you have your Z set to be "in the middle" b/w handling and less wear/feathering? I plan on getting an adjustable camber kit to be able to do this.

 

Unfortunately you can't, an adjustable camber arm with caster adjustment should be designed....but has not been yet! Notice we still have feathering......

-justin

 

Lets all keep in mind we are dealing with Nissan's "Flat" design and their "revolutionary suspension design" with the dual bottom ball joints are supposed to keep the camber at near 0 in straight line driving and add camber during turns for more contact with the road.

I believe feathering may be caused by play that develops between the lower ball joints or the lack of suspensions ability to control the bottom of the spindle during straight line highway speed driving that causes feathering.

Chris

 

hmmm, i thought the design of the new suspension was just to keep the best tire footprint on the ground while cornering, not keep the camber near "0" when straight line driving! your camber will be more negative on the wheels regardless in straightline since theres no uneven weight ditributed to the wheels side to side & nissans rear specs call for (-) camber. but when you lay into a corner & the weight shifts to one side that inside tire makes a more flat footprint, while the new suspension design allows for the wheel on the opposite side to not pull too much more negative camber thus allowing a more stable footprint on both sides allowing more aggressive turns........who knows though, there are a bunch of reasons to date that i heard for the cause of feathering. the 2 most common are:
1- non adjustable caster with too many aggressive settings causes feathering during cornering & braking(this is my belief)
2- nissans dampening/rebound of the shocks & struts causes the feathering(may play a role in it as well)

-justin

 

there are 3 threads going on right now that have suspension/alignment topics being discussed. i figured i would link the other 2 to each thread for those interested to check them out. heres the other 2 currently sharing discussions:

Just installed SPC Camber Rods/Toe Bolts- Alignment questions???
https://my350z.com/forum/showthread....6&goto=newpost

Solve Tire Feathering
https://my350z.com/forum/showthread....7&goto=newpost

-justin

 

This is the theory that I have heard some experts talking about. Under breaking, some suspension parts are flexing more than they should causing uneven wear (feathering). Some believe that designing and replacing some weak suspension components will take care of the feathering issue completely. Granted this is only theory, at the moment, as research is currently underway. The camber settings can help reduce inside tire wear but too much adjustment will have a negative impact on cornering so camber adjustment is really only necessary for those who have lowered their car too far with the stock a-arms not allowing for camber adjustment.

 

i believe that theory as well. but there are so amny rubber bushings in the front suspension that i feel would give before anything flexes. there are 2 lower control arms now in the z's front suspension, each end containing rubber isolator bushings wrapped around some aluminum bushings. the upper arm has this design too. this rubber i think would give during stressed conditions moving alignment settings into different setting areas(ie. cornering & braking). i may be wrong though, im no expert.......the only suspension piece that really looks as though it could flex would be the upper control arm, though its rigidity has to outweigh the rubber surrounding bushings!.....i replaced my uppers with aftermarket adjustable pieces.......i wonder if somone is sitting back at nissan trying to figure out this problem this hard?

-justin

 

Is anyone making a urethane bushing kit? Removing the flex of rubber might help keep the geometry in order under load changes.

Chris

 

in my previous reply i wasnt saying the bushings were to blame, though it is possible for them to contribute to the problem. i was merely saying that these bushings would give before any of the metal pieces really flex to a point of being a problem.....
to be honest, ive seen all the bushing locations when i lowered my z & added all the aftermarket suspension pieces. if you were to replace all the bushings you would have a heck of a job ahead of you. i bet the majority of them would need burned out of thier seat, they look as though they weer molded into the factory locations.....
what would really make a difference IMO is if one of the aftermarket suspension manufacturers started making lower control arms with more of a tubular design & spring perch that housed urathane bushings or even delrin bushings if you really want rigitity! even some front tubular arms loaded with upgraded bushings. all the other pieces listed in my sig that has been changed have the energy suspension urathane bushings in them. if the arms as i just mentioned were upgraded with better bushings along with the adjustable parts i have i bet the entire suspension would be very solid resulting in improved handling.......im sure somthing of this nature will arise in the future........

-justin