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More than the dealer can offer, and even more than an experienced 993 mechanic can offer, you need a 993 Ruf suspension specialist. There aren't very many of them
the suspension alignment is probably the most important maintenance item on the 993. I was lucky enough to have Dave Graff from the now defunct Borelli Motorsports set up my PSS10 rebuild. The results continue to blow my mind many years later. In fact subsequent shops I've been to (I need a new shop) have not been able to improve on Daves tuning.
if you going to drive the car then I recommend you spend some money on multiple tuners until you find someone to keep you aligned. It's a way of life not an event
BTW if I get 6000 miles out of a set of rears I'm happy, but that's not my alignment 🙄😀
your rear tire wear problem is from the red .25 LR toe on the before number. that is a massive amount of drag and would wear out that rear tire quickly.
should be fixed with the new rear toe settings.
you didn't specify what factory camber specs can't be reached, is it 2 degrees front or 1.2 degrees rear?
the current measurements for the front doesn't make sense, graph shows -.17 to -.5, like the target was -.3?
the rear target looks like it was -1.17 and they ended with -1.8 so too much camber.
very likely the person doing the alignment used the kinematic arm to adjust camber.
start by assuming the tech has no idea what is going on, just telling you a story to get you out of the way.
then ask what specific piece of hardware might be missing from the spring, you will probably get some other crazy excuse, like spring hydraulic fluid.
then ask the tech where the kinematic was set. you will either get a blank stare or told kinematic doesn't matter.
then ask for your money back and take the car someplace else.
so, the parts you need are an alignment shop with 993 experience, not a dealer.
symmetry is important, but more important is that it is easy to achieve.
from the alignment sheet results it is entirely possible someone put the car on the alignment rack, went to lunch, forgot to adjust camber and just set toe after lunch and said the car was done.
I'm always amazed with Todd's knowledge.
Todd, do you go to Morris Bros? Lehi said they have a kinematic toe tool when I asked.
"According to my tech, the adjustments were maxed out and some of the change from side to side may be due to settling but I can’t truly speak to this until I have gone over the car. Sometimes you can make other adjustments that allow you to make further camber adjustments. It also sounds like the front eccentrics have been removed and replaced with blocks. If the holes in the blocks are offset, we may be able to rotate them 90 degrees at a time to allow for more adjustment as well.
2. Was the Kinematic Arm (please see the attached pdf) adjusted in an attempt to set the camber? If so, does your technician have a kinematic gauge?
a. Yes we have the proper gauge and my tech did use it as per the workshop instructions.
good news, but strange that they didn't even pencil in the kinematic setting on the sheet.
when you bring the car back ask politely to see how the kinematic gauge works and where it is set, just to make sure.
and it would be cool to see the old factory gauge, if that is what they have.
I agree with Iain's suggestion about a ruff specialist, find out the recommended camber settings for the ruff springs and give them to the dealer.
you really don't want the factory delivered specs since you don't have factory springs/struts.
could be tough to find, maybe bilstein? https://rufautomobiles.com/product/9...uspension-kit/
hard to say about the blocks, could totally see someone cutting a custom eccentric for the set up.
in that case the camber might be locked on the ruff suggested camber, more good news.
the #2 arm is the toe control arm.
based on the two sheets you posted and the LR toe being messed up by the same amount, the toe arm and the eccentric should be double checked.
somehow that setting drifted by the same amount over 4yrs causing tire wear.
if my conversion is correct, the LR toe was off by 4mm. that is a huge amount, even visibly noticeable.
that might even be a full rotation of the toe eccentric, or something crazy.
could be the control arm bushings or maybe even the eccentric bolt being fatigued.
Todd, do you go to Morris Bros? Lehi said they have a kinematic toe tool when I asked.
haven't been to morris, I wonder why they moved here from seattle.
haven't been to the new lehi location either. when it was garff vw/porsche they didn't adjust kinematic, but that was almost 10yrs ago.
Like others have stated on a few items, the factory specs should NOT be used on your lowered car. You can’t have great handling, along with very good rear tire wear. If I could get almost 10k outta a tire, I’m happy. Inside edges wear (from 120 mile drive, too/from track) and I rotate, by dismount/mounting to get as much outta (rear) tire as possible.
My settings are far from stock, but not extremely aggressive. Car is planted when need be, and the required tire monitoring, just goes with the specs/handling. Gotta realize, the rear suspension probably has twice the load/work to deal with than the front. Lotta rump to keep planted, in a precarious layout. :-0. GL
pp000830: M030 is not mentioned in my option list. Here are a couple of pictures from the front and rear. The front springs appear black and the rears are green.
The black springs may be original, look for the pained marks to verify.
The green ones are not the original as I do not seem to recall OE springs came in solid green overall.
It is conceivable the front spring seats on the stock struts being adjustable could have been lowered with the stock springs. The rear OE struts not having adjustments other than shims in the top mount had the springs swapped out for a lower ride sometime in the past. A low cost and great option for a street car is the H&R sport kit for $2000, includes 4 struts and springs in a complete coil-over kit. Some get kits with adjustable dampening for a bit more. To each their own.
Andy
Thank you. I found this image in one of the threads. Is KT arm another name for Kinematic Arm? Is #2 the part that my problematic?
I reached out to the dealer with some questions per this thread. The service manager was very responsive. They suggested I take the car back next week for them to make the alignment as good as possible. Here are the answers to my questions and more detail from the service manager. This raises one more question. What is consequence of replacing eccentrics with blocks?
"According to my tech, the adjustments were maxed out and some of the change from side to side may be due to settling but I can’t truly speak to this until I have gone over the car. Sometimes you can make other adjustments that allow you to make further camber adjustments. It also sounds like the front eccentrics have been removed and replaced with blocks. If the holes in the blocks are offset, we may be able to rotate them 90 degrees at a time to allow for more adjustment as well.
...."
First You are getting some good advice here
I'll add a few things
1) the ride height is not particularly low, If I had to guess I'd say at or just a bit under RoW M030 which is 144+/-10 front & 127+/-10 rear
2) the older Ruf suspensions which your car apparently has included, 4 shocks, 8 coil springs, rear stabilizer bar + mounting hardware, I have pics that are hard to see but it appears that the rear springs and sway may be green, and the front black.
3) the alignment you now have w/ the possible exception of KT(which we have no way of knowing) is slightly aggressive but not outrageously so. It is roughly comparable to that used on an RS
4) the replaced eccentrics are the source of your issue, I can understand why the are used, but it will certainly make changing camber an issue. Unless you have custom blocks made, ea w/ a slightly different hole o/s, the only real solution is to reinstall the correct eccentric adjusters. I'd also guess that the rear eccentrics were also replaced as that is where the issue that they correct usually arises
5) the tire wear you are describing does sound like your issue might be too much negative camber. But other issues can contribute to tire wear, notably toe and or worn bushes. You new toe #s are all ok. It is not at all unusual for a 911 of any year from oldest to newest wear the rears out well before the fronts. I've owned at least 1 911 for the past 50yrs and have almost always had to replace rears 2 to1 wrt fronts on the street cars
6) Since you quote a post of mine w/ the rear pic, #2 is the toe arm and its bushes are usually the first to go. #4 is the KT arm, signs of misadjustment here are squirrely handling or at least a lot of rear steer. You would know it if this was too far off. a visual check is look from the side at where the wheel is located, far forward will be close to zero caster(aka KT) and a twitchy car, far back is a lot of caster and a very stable but slow to respond car. You want to be somewhere in the middle.
k7222070: By "LR toe being messed up by the same amount", are you referring to the left rear toe being adjusted from 0.29 to 0.18 in 2014 and from 0.25 to 0.18 in 2018? Or are you seeing something problematic with all 4 wheels?
Bill: I took the underbody pictures by holding my phone under the car. Hoping to take better pictures next week. I've driven the car about 200 miles since the last alignment and did not notice anything unusual about how it handles.
Is it at all possible that RUF components were only installed in the back or could it be that rear RUF springs were green and fronts black? Is there a drawback to replacing blocks with eccentric adjusters? Can you please educate me on what blocks and eccentrics are/do? What do KT and o/s stand for? Are there bushings associated with all the links that should be checked? If worn out, can this be detected visually?
Is it at all possible that RUF components were only installed in the back or could it be that rear RUF springs were green and fronts black? Is there a drawback to replacing blocks with eccentric adjusters? Can you please educate me on what blocks and eccentrics are/do? What do KT and o/s stand for? Are there bushings associated with all the links that should be checked? If worn out, can this be detected visually?
anything is possible, What I don't see is the springs w/ tenders that the Ruf suspension kits I've seen would have,
Both of your pics show stock or stock like springs and perches, from the sway bar position, above the rear links, the ride height can't be must below RoW M030
In the upper left corner here you can see a rear camber eccentric w/ the Sharpie witness marks, the witness marks are there to check for a wandering camber adjustment
Bottom left here is the front caster eccentric adjuster inboard side of the A-arm and it's lock nut, outboard side
The 2 bolts on the bottom of the strut are for camber adjustment, the upper is the adjuster and the lower is just a lock nut, sometimes shims are used here too or in lieu of the eccentric
shims, different eccentric hole o/s's(offset)
an RS camber adjusting eccentric(left) and a stock rear camber adjusting eccentric(right) the RS will allow more negative camber
ST(static toe) is the toe set on an alignment bench, shown in your spec sheets, KT(kinetic toe) is a change in toe that up and down suspension travel adds or subtracts to a given wheel, it's effect is supposed to steer the rear a bit as an aid in cornering, but when maladjusted will result in truly evil handling.
Here's a rear w/ a lock rather than an eccentric, here adjustment is done w/ the turnbuckle
Another front shong both camber and caster adjusters
k7222070: By "LR toe being messed up by the same amount", are you referring to the left rear toe being adjusted from 0.29 to 0.18 in 2014 and from 0.25 to 0.18 in 2018? Or are you seeing something problematic with all 4 wheels?
yes on the left rear toe adjustment.
but if the left toe arm turns out to be worn out you should replace both left and right.
The bushing and the balljoint can wear. A new bushing can be pressed into an old arm, but the only way to get a new balljoint is to replace the arm. Hence I replaced all my arms, best to start fresh on a 20 year old car in my opinion.
Once again thanks for all the comments and advice. And now here's the rest of the story. I took the car back to the dealer earlier this week. On a closer look, they figured the car has factory eccentrics all around. All four struts and front springs are factory. Front and rear sway bars and rear springs are RUF. They believe the front was lowered utilizing the strut adjustment and the rear by replacing the springs.
They did a re-alignment and the results look pretty good. It included KT arm adjustments utilizing a factory gauge as pictured below. The settings before and after are hand-written on the last image. Curious to hear any thoughts from the group.
the new values look fine.
did they measure the ride height?
did they check the left rear toe arm to see if the bushing or joint was worn out?
did they have an explanation for why they couldn't get these same results the first time?
would be interesting if you could get a caliper on the front and rear sway bars and post the diameter in mm so we know what the ruf bars are.
the rear toe is set right on the money so you should pay attention to any left rear tire wear.
if the left tire's inside edge wears faster than the right side like last time you'll know there is a problem with the left side toe arm.
04-09-2018, 09:43 PM
