alignment and tires

[taz069]

Back on the repair wagon here. haha. Maybe someone can explain the upcoming #'s. Took the lil one in for a alignment today $170 not bad, Now here is where i get confused seeing i could not speak to the tech that did the job. On the front axle The unpressed reading for the right side -1degree39' , left 1degree46' , allowable 0degree +/-0degree10' had to readjust to 0degree23' for both. Now the pressed reading for the right side -0degree45', left -1degree02' allowable 0degree12' adjusted to 0degree12' for the right and 0degree11' for the left. Now the tires were wearing from the inside out. Is that a bad reading?? How would things get so outta whack?? Drove straight from the merc dealership and bought new tires!! just courious as to how the alignment could get so outta whack. Thanks all hope i didn't confuse all. The lil 96 c280 running straight as a arrow and my mpg has come back up to around 25mpg instead of 18-21mpg. Just glad the extra friction is missing. Thanks all.

[wichipong]

can you post the alignment report? also for $170, it better be lifetime alignments....

[97C28O]

Average $60-80 for an alignment here..

[Vetruck]

These somewhat new Hunter Alignment machines piss me off with this degree crap on toe settings. All these techs do anymore is get the car into the "green" areas which are often dated data and recorded with the wrong overall wheel diameter. What I do know is 1 degree calculates out to about 1/32" toe. Aprox 3/32" toe in is about what is decent range for a normal street car. With that said, I could set your alignment with 24" tall tires and then you switch to 25" tall tires and the alignment toe specs will be off. Setting them to degree would be the same for both which is wrong. The car would be a little too much toe'd in with the change to larger diameter tiires.

I have no clue what pressed and unpressed mean Taz, I have never heard those expressions equated to alignment specs in my life (And I've been doing this game a long time.) Front camber should be about -.5* on both sides, Caster should be about 5-6 range (I have mine more at race specs using about 8* static and about 12*plus dynamic. Rear toes should always be in about 3/32 also for an independent rear suspension to gain tracking stability at high speeds. The rear caster for these car is good at about -.8 to-1.2 range for spirited street use.

As for going out of alignment, all cars do from bushing, balljoint, and tierod wear.

[Dearlove]

while we're on to subject, what are you thoughts on the LCA bushings? under brakes they are designed to change to alignment. just wondering if thats going to hinder me on the track?

[Vetruck]

while we're on to subject, what are you thoughts on the LCA bushings? under brakes they are designed to change to alignment. just wondering if thats going to hinder me on the track?

Where did you read that? I have never heard of engineers building in any changing geometry for braking. On the contrary, A-arm bushing flex is a problem that causes setback in most cars because of flex. It is when you want them not to move-why? because under brake dive compression of the front suspension, the chassis rakes forward and the car naturally looses caster as a result of the lean. Now on the other hand, caster has a dynamic gain in suspension squat due to shorter geometry increasing the reading- so this counter acts brake dive forward lean/or rake. Whne the bushings flex on the A-arms under braking, the tire stopping power pulled the wheel back in the wheel well (setback) where the front bushing pulls outward (sideways) and the rear bushings push towards the center of the car. This brangs the lower ball joint rearward and thus decreases caster (which is stability).

When I clocked my KMAC bushing into my chassis, at mid point of adjustment the oblong centric style bushing has the holes centered either down or up about 1/2" based on how you clock them. I leave my fronts on the lower clocking and the rears towads the higher clocking. What this does is lowers the front bushing of the a-arm in comparison to the rear bushing. The thrust of the chassis weight through this bushing plain rear to front (rear and front of the control arm) will aid in the car brake diving, or anti diving. With the front set lower and the rear higher the car has a slight bit of antidive. You loose this the more outward or inward you have to clock each bushing to get more or less caster and camber based on how they are manipulated, but you do have a choice to go up and around or down and around, The front ones go down and around as you adjust, and the rears the opposite (up and around).

Most alignment techs would be clueless to this type of beneficial adjustment. They just look at the alignment machine and do what it tells them to get the proper static readings. Most are clueless to even comprehend what a suspension will do in dynamic form and can not think that complex. They are taught to do a job, and they perform that job through basic training. Guys doing it for years will have much more knowledge because they were taught old school and are generally learned through some sort of race team participation.

[Vetruck]

Im teaching you guys secrets, I usually take a few people money at the track before I start revealing how to make everyones car handle better on forums ;)

[Abbaso]

Im teaching you guys secrets, I usually take a few people money at the track before I start revealing how to make everyones car handle better on forums ;)

Why Thank you very much kind sir

[Dearlove]

The design of the LCA bushing is odd. It's hollow. And the centre is supported with a Y set up. Maybe it's nothing

[Vetruck]

They make the bushing with voids so the bushing hangs in tension like a spoked wheel. This way a more firm durometer of rubber can be used . In the event of a hard abrupt impact the voids will allow a little give that a solid bushing would not. This give keeps a comfort level but lacks performance levels when hard pressed into high g situations. It was done in the name of Mercedes comfort while having a more solid initial road feel to the driver. In other words, those bushings are firm up to probably about 0.8 g's and then anything above that they give in the name of comfort.

[Vetruck]

Why Thank you very much kind sir

Beware of the guy with the Gene Simmons Simpon high top drive shoes undone and the wamtabee push broom guitar- I always voluntee to sweep the tracks so I can study the surface for braking zones- and people think Im out doing the sh*t job.2332

[Dearlove]

ah, that makes a lot more sense

[taz069]

I will try and post a pic of the alignment results in a few hrs have to some running around and pay some bills. I took a pic of the alignment printout will try and get it sent from my phone here shortly. I dont have a scanner or would go that route. Thanks all.

[taz069]

2336

[taz069]

maybe ya can zoom on it

[taz069]

...

[taz069]

Don't look at the f'ing toes!! you all will have to zoom in to read it. Please explan ve. I did not find out what machine this was done on. From my understanding is they had to do a 150lb load on all four tires with a simulated full tank of fuel. I have no clue hope the above pic helps a little. I can say this much what it was set at damn sure wore out the inside of the front tires

[Vetruck]

I can see it, I'm getting an "Invalid Attachment" message.

[Vetruck]

Don't look at the f'ing toes!! you all will have to zoom in to read it. Please explan ve. I did not find out what machine this was done on. From my understanding is they had to do a 150lb load on all four tires with a simulated full tank of fuel. I have no clue hope the above pic helps a little. I can say this much what it was set at damn sure wore out the inside of the front tires
What good alignment shops will do(its why this costs more then usual basic alignments) is they will set the car to specs on the alignment rack. Then, they will pull down a load onto the chassis with come-alongs to simulate bump travel of the suspension to check the camber gain and mainly the dynamic toe settings to make sure they stay within reason through travel. If the Idler arm is bad the toe will often change. these cars are known for bad idler bushings from what I have read. Mine is fine though but I do not know if the previous owner replaced it.

[taz069]

Ve I wish you could see it!! I have opened it on my phone and lap top. These are some readings I want you to see!!

[Vetruck]

Can you send it to my email

Sakeed123@aol.com

[taz069]

I can say this 've!! When I let go of the steering wheel and nail the brakes it is an arrow!!!!!!

[Vetruck]

You car was toed out quite a bit on the front end. The toe out is good for corner entrance because it builds Ackerrman, but on straight line braking and high speed freeway driving it will make the car wander. Correcting that will keep the car straight under braking- it no longer wants to turn-in fast in either direction as each tire is fighting for direction somewhat independently.

Edit to add info_

I sent you that email response David, but looking at it again I see why they messed with your rear camber and took it slightly out of spec. They can not correct the fornts without a Kmac kit, and when the corrected your front toe the car with that much caster split (you have about .8" more caster on the right- should be about .3 to .5 range of split for road crown- just a little more lead on the right side to track straight) your car will pull slightly left on braking. Byu the tech "Bandaid fudging" the right rear camber flat and the left rear camber leaned in, the right rear tire will dominate becuase of rear toe in and produice a very slight amount of rear steer taking the car to the right. THis counters the front taking it to the left and low and behold you brake straight. A smart tech, Im impressed.

Dean.

[Vetruck]

Here's some pics when I checked my car for bump steer last year and ran all ride height geometry ever 1/2" fender lip height off the ground from 27" down to 23"2337

2338

2339

[taz069]

My be that is where the cost came in? The manager or shop rep said I had bolts loose in the front end ! What a joke I bussted my left nut getting everything tight that I replaced!! Hehe the whole front end!! But with your sign off VE I feel a lot better!! Gonna have to make a trip and shake the dudes hand!!

[Vetruck]

These car are notorious for loosening things from what I have read. I could not even get any one of the four front A-arm nuts loose on my car they were so damn tight. I cut them off. Looked like the threads were fused together. I installed the KMAC kit with all new bolts that came with it, and I was under there 3 times that week rechecking things. I should probably check mine again because its been several months. I would know if one slipped just from steering feel, but wouldn;t hurt to check and retorque them one more time now that some months have past.

Always remember, if you bust a left nut, you still got that right bad boy- just guard him with your life cause it's all you got left.

[taz069]

21 mm on the bushing part and 19-17 mm on the rest. I did everything correct! It is of little matter know seeing it be correct .also on the bushings part lower that is. Mine are locked in With only one nut holding it all in place, it has no and I mean no way of adjustment, not by them 2 bolts anyway!