The shim is for Camber, not Castor...2 totally different things. To remove the shim you have to losen other parts of the suspension and just taking out this shim you will screw up the toe. If you remove the shim for less Camber in the LCA you have to realign the front, I am very positive about this.

 

correct...you have 2 holes in the LCA to set Castor and that is it.

 

And the correct answer is: (I better get rep for this one! :P )

Your tie rods attach to the front hubs ahead of the bearing so as you remove shims from the LCA you shorten it and pull the hub in. Doing this adds toe OUT. The proportion of this adjustment is not linear, but exponential because it works on an arc.

In the rear, the toe links are behind the bearing so as you remove length you increase toe in. Same type of equation as up front but may change at a different rate because of distance between the attachment point of the toe adjuster and the bearing centre.

And yes, you really should have the car completely aligned after removing the shims. What you theoretically could do, is measure the number of turns (or degrees of turns) required on the tie rod/toe link when you remove/add shims and just make the same adjustment each time. Still though, it's in your best interest to realign the car properly.

(Bow)

 

Art...Reps for you!...heck I explain tons of stuff around here and have not received reps in a long azz time! LOL

I have lost breath on this thread but you explained it further than I did and explaine why better than I did. I was multi-tasking while typing my post..LOL

 

Rep added.

OK, i see. as all that stuf i have now is adjustable essentially at next visit to mechanic i wil lneed to mark positions on rods with paint or something, or simply pay him $150 every time i want to change it what is probably more time effective anyway. makes sense.

as you all say it has to b re-aligned, then i will not touch it. interesting, i did not think it had an exponential arc there. thanks anyway, nice to know.

 

i did not think that moving upright 'in' by removing shims would affect other rods, but now it makes sense.

 

As a side note, the neg camber upfront will not contribute excessively to tire wear because there isn't much weight up there. The rear will a little more.

The original comment regarding toe is the one you need to be aware of. Toe will cause tire wear more than anything else.

Unless you want to learn to do string alignments, you're probably better off to either live with tire wear or live with normal alignment specs.

 

utkinpol, for DE's and Autox why don't you just use Toyo RA1 or R888, that way you can have alignment specs more suited for the street and track?

Remember it is the amount of toe that chews tires, not so much the camber.

You can not just put paint marks on your suspension parts and remove shims at will and replace them at will....THIS WILL NOT WORK....you must have the car aligned each time. Your idea with shim removal and replacment is not going to work...forget about it....pick an alignment and live with it.

I HIGHLY suggest since you are new at the track/autoX that you use street tires or at max R-Comps...not Hoosiers....and reduce your alignment specs back to around -2.2 front zero toe and -1.9 rear with around .14 toe max. As a new student you are putting way more into mods ect then learning driving skills. Relax, have fun and just go drive the car.

 

I agree. Over the years I've had students with crazy cars with crazy amounts of money in them and they can't even figure out the "line", smooth transitions, or looking thru the turns instead of looking right in front of the car . . .

Relax, have fun, and enjoy the car!!!

 

i do have way more fun from doing all those mods and alterations and exploring effects from different settings and setups than from 'driving the car' alone, to be frank. it all works as a complex of things, not by itself. i drove it stock for more than half season, and it was plain boring.

again, i appreciate advice from people like you who do know this sport and never discard it blindly. still, current alignment will stay for now. next time i will go to mechanic may be i will reduce it. for now i am just curious to see how hoosiers set will work compared to regular dot r-comps like ra1 you mentioned or current v700 kumhos. i set my own goals and my own schedule and it got very little to do with overall learning efficiency. i really have no goals to be next Patric long or even go to blue/black running group. i do not even think tracking by itself is what i will do a lot. i have not even decided yet about this.

i really do not have any 'goals' and all i do is just go out there and have fun, and my way of having fun most likely has nothing to do with what would be most efficient way to learn here. some microscopes are damn handy to be used as hammers to hit nails, if you like, despite of level of frustration it causes to professional scientists.

more to say if my primary goal would be to become world class driver i would not even bother with 997 car and got another miata instead. nevertheless, it is all fun and process itself for me personally is way more interesting than any final result. any mods or any setup does not prevent any learning. it makes it more complicated, reduces typical feedback from a car significantly, yes, i know al that, still, it all still works, i still usually come within first dozen of drivers this season in raw time out of 40-60 cars that do run, despite all my mods, so, with time everything will come to its places. and I have no time restrictions here, at all. i may not even run a single time more this season - but there is always a next season. catch my drift here? it`s no work, it is hobby.
so even if all what you say makes total sense - in my system of priorities it doesn`t as our goals are a priory different.

 

problem here is that 'enjoy the car' part is understood totally different by different individuals and there will be no consensus on that part ever.

as of first part of comments - your 'students' did not buy their cars to impress you. instructing is definitely an ungrateful job to some degree, i would guess may be hardly 0.01% of Porsche car owners are even interested in aquiring proper driving skills by itself. i can say quite definitely i do want to learn to some degree but is it a N1 priority for me? very highly unlikely.

most of all - at almost 40 years old i do know my limits, i know my true interests in life, flying at 150mph on somebody`s spilled oil into the wall is not one of them, so, all what stays relevant here is to waste some money on some stuff that does appear to be interesting at this moment. mods, running car here and there, more mods, removing mods, running car again, etc. there are always people who prefer to answer 'you do not need it' to any quesion asked, it is normal to expect but is no reason not to ask questions. like on GT3 forum somebody answered me what i also wanted to know - each 1mm of shims reduecs camber by 0.1 degree. and this info came without comment of what camber is needed for me personally, then with continuation of what tires are needed for me personally, etc.

so, what level of understanding is possible between people like pca instructors who see driving as their N1 life goal and simple easy minded folks like me?
probably close to none. is it a reason to stop communicationg to each other? i guess - probably not. but it is not my call. i like to yak on forums and will unlikely stop any time soon.

 

utkinpol, at least you have a good attitude about all this and you enjoy it at your own pace...just keep having fun and learning...Reps to ya!

 

My comment was releated to mdrums post since he is an instructor as well. We all see that kind of stuff. Over the years I've learned to keep it simple. When I was younger I was ***** to the wall but it was hard work!!!

 

like i told you before - i am not even a half such an @sshole as i paint myself in those threads. which way 'not a half' - i would not say,
it is probably an open matter for interpretation, but real life is never what it seems to be online, usually.

on a serious note - i really want to try hoosiers with proper setup. experience in the beginning of this season with -2.4, -1.9 camber and soft springs ended up with ruined tires. now all that got adjusted.

when i will be done with that experiment i will put camber to optimum for RA1 toyos or comparable r-comps as i cannot justify a budget for 5-6 sets of A6 tires for a single season. yet.
but i do intend to burn at least one set of A6 tires properly with one club to get a proper feel of it. as i run with 3 different clubs and most of folks who run there are same people - it is not very difficult to arrange this and is very helpful for subsequent analysis.

like i said - even if all that does not have much of particular practical sense - it is entertaining, quite fun and helps me to keep interest to the concept, otherwise i would probably already stopped coming to auto-x altogether.