545svk

As the tires are shot anyway, and I like learning about the car, I will try this. One question, how do you adjust the toe in / out without lifting the car?

Or is this measure, lift, adjust, drive, measure and repeat?

Thanks

mark kibort

I usually do a half a turn on both tie rods...best to lift the car and just adjust and repeat. you do both tie rods, so the steerng wheel stays centered in the car.....
so, place the straight edge on the side of the tire/wheel and mark the spot on the driveway with the magic marker. do it the same way both front to rear and side to side.... roll car back, or slide measuring tape accoss under car and measure the dots. you should see about .25 toe out from that wear patterns if its been going on for a few 1000 miles.

don't forget to counter hold the tie rods by the flat spot... don't want to give too much stress to the ball joint connection point.
Yes, then go out and drive and come back and retest.....

mark kibort

the shop way is probably not the best way to get a an aligment done. reason being, is during the lift phase, the car is way out of wack, and never gets back to road driving height, even with that shop weighting technique. the best way is to do the alignment and then check after you are done... or check before hand that nothing is lose, and then take it in to have the alignment done after some decent road miles that day! (not just around the block.... 5-10 miles )

Randy V

Yes, I agree this is the procedure called out in the WSM, however you are still leaving the amount of pull down at the tech's discretion - you will never be sure he pulled it all the way down.

Measuring the fully settled state then driving the car while employing some maneuvers (hard cornering and sudden stops) to fully settle the suspension is the only way to be sure.

dr bob

Mark believes that his method with stick against the tire and the crayons/markers is accurate. It may be 'close enough' to get you safely to the alignment shop but not much more. The faces of the tires are not reliably true to the wheel, and the marks he makes on the asphalt are wider than the total allowance at tire edges. Like using a yardstick to measure thousanths of an inch.

Find a good shop that can do it correctly, or learn to do it correctly yourself. You can buy or build the needed pieces if you want to take a run at it yourself. There are several references to DIY alignment here on Rennlist. Search for posts by Earl Gillstrom to find a reasonable method using strings and a machinist's scale for setting toe.

hacker-pschorr

I think we are over complicating things here, pulling down a 928 to proper ride height isn't very difficult which is why I find it so frustrating we are so stuck on "no lift" alignments.
Yes I've done it myself.

Quite frankly, if an alignment tech cannot properly pull down a 928 before doing the alignment, I wouldn’t trust them with any other aspects of working on my car either.

Randy V

All the more reason to ensure it is done properly yourself.

Most 928 owners only use an alignment shop for that purpose - rarely do they also do other mechanical repairs. I'd trust a guy to do my alignment if that's all he does every day for a living.

mark kibort

that's not entirely true. its not anywhere near using a yardsick . yes, it is good to remove a problem on the toe, and that can be as good as an alignment shop. ive done it several times, shown the info to the tech and we laugh about how close it is. both, toe and camber. the faces of the tire are true enough. I verify that with the distance to the rim, which is true. You have to think about the mark im making on the ground and the straightedge I'm using too. the mark maybe thick, but its at the point where it contacts the edge to where it counts. so, that is razor accurate. think about it this way...I could use spray paint as well, and the end of the paint is RIGHT where the straight edge is positioned. you have always missed this point. also, its consistent from side to side because of how you measure. so, in the end, its accurate and relative to 1/8" easily and repeatable. and Toe is one of those things that change with bumps in the road anyway, as well as weight in the car, so my way, is a very good way to permanently adjust toe. in fact, ive had better luck with my way than most of the alignments ive had. but now, I always start with a good one with a huntermachine. I can adjust from there if need be.

anyway, if your objection is the face of the tire, that's an easy fix by putting some parts on the level to hit the rim only. and if you don't like the magic marker, you can use a can of spraypaint and get an exact position on the ground..... its repeatable and very accurate.

mark kibort

for those playing at home...... the pull down rarely works because they don't know exactly how much to pull the car down too... if they use fender markings its crude! in fact, a lot more crude than my level/magic marker technique. if they use ride height, its closer, but ive never seen anyone do that. the WSM shows a specific weight to pull the car down with if I remember correctly..... the problem with that is, there is SO much sticktion in our suspension with all the stiff rubber and angles, that pulling down doesn't take care of all the setting issues. It can be close, but its not the best way... the best way is to drive it on a Hunter machine... zero out runnout by rolling back and forth, no lift the car, and then do the alignment.

I should make a video of my home technique. its pretty good and like I mention, its very close to the shop technique... just takes a lot longer and really is to fix a gross problem as an intern fix before you hit the alignment shop.

hacker-pschorr

What a load of BS

I've done it a couple times myself at the local shop and they've been aligning 928's for over 20 years. Nothing to it for an alignment tech with half a brain.

Again, if you cannot rely on your alignment tech to know how to properly set ride height, they are not qualified to do anything else on your car.

Next thread: Why Jiffy Lube is the best place to have your oil and transmission fluid changed... I mean, that's all they do, day in and day out. A 928 is just another car for them to work on...right?

The WSM is very detailed with the alignment procedures. If your place cannot follow those steps, time to find someone that can.

dr bob

Mark, I guess the reason I continue to doubt the accuracy of your method is that the difference in distance between front and rear of an 18" wheel at correct toe is a lot less than 1/8" total. Grab your calculator and remind me what number you think it is to get 15-20 minutes of total toe-in at 18" spacing. Then remind me how you think a stick pressed against the tire is good enough for that. I fully understand how you put a mark at the stick and only measure the cutoff edge of the mark at the stick.

For a run to the alignment shop it may be OK for you. For an emergency adjustment between sessions at the track, it may be OK for you. Please add that disclaimer to your description of your method, so folks won't actually believe the alignment is correct after they try it.

----

For those playing at home, the normal error tolerance/allowance in most commercial machines is greater than what the 928 will tolerate. Find a shop that has a new machine, a capable/knowledgeable/willing tech running it, and you stand a chance of keeping tires on the car. I quickly went through some expensive tires after having the car on a recommended rack with the recommended guy in the recommended shop. Took it back for a recheck, and his machine still showed it the same (perfect) as it had left. Everything was fine except the tires were getting corded quickly on the insides. In self-defense, I started looking at alternatives to commercial alignment. I started off with the basic string alignment that Earl Gilstrom uses, and found that my 'perfect' alignment wasn't really that close. It was only toe'd out half a degree, should have been toe'd in a quarter of a degree. Using the MK method at 18", that's a difference of 0.141" total between what was there and what it should have been, or 0.070" at one end of his stick-against-the-tire and magic-marker on the pavement measurement, or 0.035" difference at each mark. That 0.035" is 3x what the difference is between zero toe and the recommended 15 minutes at 18" wheel edges. It's way less than you can see on the tape measure, even if you have "perfect" pen marks on the ground. At a couple $hundred per tire, I can't afford that kind of error.

So I spent some time building some laser fixtures that attach to the wheels, worked out a method that works perfectly every time, and never even consider taking any of the cars to an alignment shop any more. Not saying that you can't get a good commercial alignment, just shop carefully for the right machine, recently calibrated, with the right guy doing it. And don't let them lift the car unless you are sure that they can pull the body back down to your car's normal height front and rear, whatever that is, and hold it there while they adjust.

mark kibort

its not a load of BS... I forgot the value of the weight they use, but if the springs are not identical to stock, and not worn at all , you could get pretty different values. ive never had a good shop do an alignment right on a 928. the hunter is the only way.... it was many many years before I understood enough about the 928 as to why. sure, if you get a good tech guy, they might get it right, but its not guaranteed.

mark kibort

Bob,
Again, its not that far off the actual hunter adjusted alignment. It's just harder to do.
I am not advocating this for permanent adjustment, but if done right and double checked, it can be.
I run this kind of alignment for 1000s of miles with no bad wear and we are talking DOT rubber, driving on city streets and my first sessions at the track.

the trapezoid you get (or rectangle ) will be 71" by 25"
all you care about Is the 1/8" between the two side
the front mark is about 25" from the rear mark.
1/8 divide by 25 INV TAN. gives you 15mins total toe. (7 min per side)
or .25degree total toe.

1/8 of an inch is pretty detectable and repeatable. It gets you right in spec.

If you are finding hunter machines that are not calibrated or adjusted...... well, that's more the reason to check things with my method.
tell you what, worst case , you might be 0 toe.... so no wear really, or you mght be alittle more toe, like 25 min vs the spec of 15min. again, the range is pretty wide that wont wear the tires, but if you are set up at .5 degrees toe'ed out, you will get some nasty inside edge tire wear, pretty quickly.

Bob, remember, its the edge of the level that is making the mark on the ground... its pretty precise..... the size of the marker, as you admitted, doesn't matter. its more the surface and how you hold that level to the wheel

EDIT: the 25" distance from front to rear is how you get the most accurate angle of the tire. you put the level on the wheel at an angle .. as the mark hits the ground its about as wide as the tire ... you can even make it wider to get more resolution if you want.

dr bob

Mark, for grins, see how much pressure it takes on the stick/tire to move any mark on the ground 1/32". That's the difference between OK and not OK if using your method. Extending the stick further from the wheel center amplifies the error as it expands the measurement range.

mark kibort

I'll try it again. It's not a stick, its a mechanical level. It's not flexible.
it's a pretty solid. Pressing the level against the wheel or tire, is pretty firm, and is very though to move it at all, even 1/32, but one (which is 1/16 over both tires) by the way, that would be another 7mins (.12 degrees) , so not enough to really make anything that bad on an alignment.
Its pretty accurate. If I had a brand new set of tires, I would have no problem trusting the toe after I measured it to be 1/8 toed in. its obviously not toed out..... no way.... worst case It might be a little more toe than spec or near 0. Neither one would be that much to worry about.