DIY Alignment -- Did I do it right?

[Captain Obvious]

I agree completely. It comes down to the skill, understanding, and patience of the person doing the work. The best laser guided rack on the planet can't overcome everything that a hurried, inexperienced, and probably creatively uncaring tech can come up with. Technology can help make it idiot proof, but nothing ever is completely.

If you are going to measure and adjust the rear alignment, then you need more than just a tape measure, but if all you can adjust is front toe, then you can get an accurate thrust angle compensated alignment with the tread measuring method. Just have to understand how and why.

[Zed Head]

10 hours ago, Consigli said:

But I think if you spend enough time fiddling with the kite string, chewing gum, plumb bob and bubble balance you should eventually be happy with the results too. 

It's easy to miss the point of what's really being said here, especially if you take it to a shop without actually trying it yourself first. 

There is only ONE adjustment that can be done without a hammer or big lever or jacking/bending suspension components around.  Toe-in.  That's it.  Nissan has provided zero adjustment anywhere else.  No camber, caster, rear toe, nothing.  Everything else is locked in by the part of the unibody that it's bolted to.  The typical alignment shop has a book that describes what procedure to perform on whatever car that's brought in.  People have described taking their Z in for alignment, then paying nothing (and having nothing done) because the guy checks toe-in, it's in spec., and there's nothing to charge for.  

Wheel balancing is a whole different thing.  A re-centered wheel is nice also, but the same two nuts were probably turned to get there.

Just wanted to be clear on what typical wheel "alignment" entails for an S30.  Don't pay too much.

[Consigli]

1 hour ago, Zed Head said:

It's easy to miss the point of what's really being said here, especially if you take it to a shop without actually trying it yourself first. 

There is only ONE adjustment that can be done without a hammer or big lever or jacking/bending suspension components around.  Toe-in.  That's it.  Nissan has provided zero adjustment anywhere else.  No camber, caster, rear toe, nothing.  Everything else is locked in by the part of the unibody that it's bolted to.  The typical alignment shop has a book that describes what procedure to perform on whatever car that's brought in.  People have described taking their Z in for alignment, then paying nothing (and having nothing done) because the guy checks toe-in, it's in spec., and there's nothing to charge for.  

Wheel balancing is a whole different thing.  A re-centered wheel is nice also, but the same two nuts were probably turned to get there.

Just wanted to be clear on what typical wheel "alignment" entails for an S30.  Don't pay too much.

On my car, the toe-in was slightly out and tweaked into the "green."  And you are right - that is the only adjustment. The wheel balance was way off. A hunter road force balancer was used. This made a HUGE difference. The car feels firmly planted to the road at high speeds and has no more vibration or wander. The irony of all this is that the last wheel balance was done at a Nissan dealership on a regular spin balancer. It took the Lexus dealership to get it right. I use the "Black Pearl" alloy wheels. Lexus used lead tape on the inside so no lead "sinkers" are showing on the outside of the wheel. 

So sure, set the alignment yourself if you have the skill and time. But open up the wallet and splurge for the road force balance. You'll be happy you did. 

[Captain Obvious]

Yes, front toe is the only adjustment, but it IS a little more complicated than that. You could have the front toe spot on but if the line through the center of the front toe isn't parallel (or coincident) to the thrust angle from the rear wheels, the car will pull when you let go of the wheel. You have to take the thrust angle into account too and compensate for it or the car will drift.

But that's why you can succeed with just the tape measure on the treads... If you complete step one "make the car go straight when you let go of the wheel", you have successfully got the front toe aligned symmetric to the thrust angle.

And after that, there's the matter of putting the steering wheel straight. I guess you could consider that a cosmetic issue, but my little engineering brain can't deal with driving a car where the wheel is all wonky even if I know the underpinnings are working properly. Just can't handle it.

[Mark Maras]

Circletrack.com has a good how to about four wheel alignment titled "stringing your car". Although I have not tried it yet it is an interesting read and makes a lot of sense.

[Zed Head]

Don't confuse opening a fat wallet with getting value for what you pull out if it.  And on a DIY-focused site, using bubble gum and kite string to get a job done right should be lauded.  It's why we're here.

[Consigli]

My hats off to those who can do everything themselves! I wish I could. And of course, time is money, so some must pick & choose the things we DIY and pay for the rest. In any case, for everyone's info, this is from the 1978 FSM

[Zed Head]

Don't forget the rear wheels.  A fun experiment would be to take your car to several different shops and see how many take your money for aligning the rear wheels and "setting" camber on the fronts.  Take a fat wallet.  I can't give in on the "just spend the money" argument.  We're here to show people what they can expect from these shops.  What's involved in doing the job right.  There's no camber adjustment for a shop to make.

 

[charliekwin]

Thanks for posting that!  I remember checking at least the steering, wheel and general info sections of the FSM and my mostly-useless Haynes manual and didn't find specs, and Google returned almost nothing.  I imagine/hope this thread will be of some use to someone in the future as well.

I wouldn't be surprised at all if the shops in my neighborhood somehow managed to show me a before and after printout of freshly aligned rear wheels on my car.  

[Zed Head]

Taking the other side of the argument - the specs. are there for confirmation that everything is right.  They can be measured.  They could show worn bushings, or bent parts, or signs of a previous accident, or even find a basic problem that was built in to the car (some say that older 240Z spindle pin bores were drilled off design axis).  If the simple toe-in spec. doesn't get the car right, then the alignment shop visit is probably in order.

 

[John Coffey]

BTW... caster on the front is adjustable using washers between the TC rod and the first big washer and compensating for that thickness when you tighten down the 17mm nut on the backside of the TC rod mount.  You can also adjust rear toe slightly using brass shim stock between the inner LCA bushings and the front body mount and the rear transverse link mount. Camber is adjustable up the .5 degrees on all 4 corners if you slot the strut tower mounting holes.

Edited February 16, 2016 by John Coffey

[rossiz]

i just enjoy working on my car, and getting it set up just right by myself with simple tools and some ingenuity makes for an awesome saturday in my opinion.

when i was a kid my dad taught me to be a fearless tinkerer - he promised me that as long as i paid close attention when taking something apart, i would always be able to put it back together again. he was taking apart the toaster on the kitchen table (on a newspaper, of course) to fix the auto-up mechanism and he showed me how to group fasteners by function, recognize wear marks on mating parts and put sub-assemblies into separate piles. i was probably 6 at the time. i asked him where he learned how to fix a toaster - he smiled and said it was the first time he'd ever seen the inside of one. i tore apart every toy, old clock, broken camera, etc. that i could get my hands on just to try and see if i could put them back together again. probably a pretty common story w/a lot of folks on this site i imagine.

it's a huge point of pride/satisfaction to be able to work on and improve a simple mechanical device - for me, anyway. that's why i have a 38 yr old car. sure, it's cool to look at and fun to drive, but truth is i get just as much joy out of fixing and modifying it. and i know my dad would be proud of me for stringing the front end the way he taught me when i was in high school.