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Discussion Starter #1 (Edited)
Caveat! - if you start messing with your suspension you WILL get things coming loose etc so be prepared. If you dont want to deal with the consequences then its better to take it to someone who is experienced.

Thought I'd stick some phots up showing what I've been playing with this week. Lost of people think alignement is some sort of black art but all you need is a bit of homework to understand whats going on, a fair bit of spare time, and a few homemade tools and you're good to go. I don't work in the trade and only know what I've worked out by trying stuff and reading books/internet so excuse any poor terminology. There's probably better ways of doing it so please let me know as I'm learning as I go anyhow.
Everything here looks fairly rough but if you do it in a way that minimises error then I found it wasn't too bad at all. My car drove completely straight drifting today. Some things can be rougher than others without causing issues. Camber for instance isnt' too bad if its a little different on each side. Toe (tracking) on the other hand needs to be as accurate as possible.

First you need one of these.

Then fit some of these. I've had most of them for over a year now but never got the traction arms until recently. I was running the upper and lower arms a bit wider than normal but was limited by bumpsteer (toe change on compression of the suspension/coilover) through having the oem traction arms.

Looking sexual :)


The first thing I do is get them setup roughly so they look ok as a beginning point. This helps keep down later adjustments as doing one thing tends to change another. I wanted to make the car wide. I found the upper camber arm was the limiting arm so I set that out as far as it would safely go and then adjusted my lower arm to get the camber looking good. The traction arms are tough to judge because you have to experiment a bit (more about that later). I set them around the mid to long point to start with. I then did the rear toe arms to make the wheels look more of less straight.

I then set the camber more accurately. Camber and caster gauges are quite cheap to buy but I havn't got one so just use a bit of wood and a builders level! If the top of the wood is 1cm away from the wheel when the level shows vertical then I count that as aprox 1 degree negative camber. I'm not sure if thats what it is exactly but it works for me and looks close.

The amount of camber on nissans increases as the suspension compresses so I've now reduced the amount of neg camber on the back to roughly -0.5. When you compress the shock this increases to around a couple of degrees neg at least,maybe more. We don't want much rear camber for max grip because when drifting the car doesn't roll so much because we're on lock most of the time. Some people purposefully add neg camber to loose grip if they are running very wide wheels but I think this is a bit dumb because you just go through tyres on the inside real quick.

Once camber is done it gets a bit more awkward. You need to find the center line of the car. The good thing about doing the alignement in this way is you are measuring off the car and not just wheels in relation to each other like at the tyre places.
Use a piece of string and preferably a proper pointer weight (I've just used some washers and a split pin because I can't find the pointer weight thing) to mark off equal parts either side of the car at the front and back. I used the subframe mounting bolts at the rear and the lower arm bolts at the front.

You then draw a line between each two marks at the back and the same at the front. Measure half way along each and you can then draw a line through these to mark the center of the car. This is used for doing the tracking/toe.

I used a couple of coilovers as weight to wrap string around and then lined these up with the middle markers to show the center line. I then drew it on the floor with a marker pen.



This is my 'toe gauge'! despite looking ridiculous it worked really well. Seeing as I'm using the center line I could just use half of this but you need to make sure its perpendicular (at right angles) to the centerline for measuring so its easier to do the full length and line it up withe the front or back of each sides tyres.
Its just some wood that is at right angles to stand up and can be marked on the sheets to measure the alignement.


Before you can start measuring you need to mark a point around the tyres that you can measure to.It needs to run all the way around the tyre at the exact same spot. Ideally it should be in the middle but this isn't always practical. To start with I tried measuring around and marking off the half way point on the tyre tread but eventually found it easier to just stick the car in gear and run the wheel around whilst supporting a pen on some wood to keep it steady. As long as the line meets as the tyre goes full circle then it is probably straight and accurate. You can see my pen mark on the tyre here:




Put the toe gauge behind the wheels (rear in this case). And mark the point if crosses the center line.


Now mark on the toe gauge where the tyre mark is on each side as per the picture above showing the tyre line. You are not comparing each side to each other now, you are comparing each wheel to the center line so the next step is to move the toe gauge infront of the wheels and compare the marks. This way you can see if the wheel is pointing in or out and adjust the toe arm (rear most one) to give zero toe (or whatever you require). I found the adjustments were quite equal front and rear. If you moved it in by 1cm with the toe gauge at the front it would adjust the rear out 1cm rather than anything odd happening.

Once the toe is looking good I started to look at the toe change through the suspension travel. This is what the traction arm effects the most. I made this amazingly awesome contraption:


The idea is that the screws contact the rim and when you lift or lower the car you can see how far the wheel has moved from is original position. If there's a gap at the front then its toeing in on suspension movement and if theres more gap at the back then its towing out on suspension movement. Its made harder with nissan suspension because the wheel shifts position forward and back as well. Unlike a race car with proper double wishbones (and the Rex ;) ) which stays quite straight.
I jacked the car on the diff and removed the coilovers so I could lift and lower it easily.

I found the best way was to start with the car high and drop it down. As it drops you get more neg camber and the toe toes out a little more. This way the screws on the measuring thing dont move, and the wheels moves away from them and you can see by how much for measuring.

Now this is where I need to try things out some more but I'll describe what I've found so far. The car drove really well today at pod but I'd still like to experiment a bit more to check I've got it right.
With the traction arm out quite far I got about a cm of extra toe out as I dropped the car; quite a lot of bumpsteer.
With the traction arm ats its shortest I got about 4mm of extra toe out so this is how I set them up, smaller rather than longer. I must be honest it wasn't what I expected as I'd lengthened all the other arms so thought I should do the same with the traction arms? It may be there's a point in between that more ideal but I ran out of time and settled on it being short for now.

I've got fairly narrow wheels and tyres (205) and no spacers on at the moment. Once I've sorted the arches it should look pretty damn mean.
 

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Just thought I'd post up what I've learnt so far and a couple of links which are quite handy.

I'm looking at setting mine up for an trackday which I have soon, so I also did a bit of digging and read about the 'string box' which Royal mentioned, but to make things easier I found that a 'string box all around the car isn't totaly necessary as my R32 GTST has equal track front and rear (I'm pretty sure the R32 GTR also has equal track but not sure about the other Skyline models) so you only need to use string down one side of the car. This is explained in more detail on the second video clip


http://www.youtube.com/watch?v=sZoL1gaWedA

http://www.youtube.com/watch?v=gjcP07VKVZM&feature=fvwrel

http://www.youtube.com/watch?v=RpEwSeSJVW4&feature=related

As for the camber I've done a similar thing to Royal, using a spirit level and ruler to measure the gap. The following link helps you calculate the angle a little more accurately but Royal's '10mm = 1degree' isn't too far off.

http://www.easycalculation.com/trigonometry/triangle-angles.php

I hope this helps

Neil
 

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Discussion Starter #7
Bit of an old post :) I dont have a car at the monent although regularly find myself in the for sale section....

I did start using the string method and it did the job for me. I think the most useful thing about all the messing around was simply learning how it all worked and trying so many different setups in the process that I really got to know the pros and cons of different settings. I reckon I got one of the best DIY suspension setups possible for my driving. I dont think the 'generic' drift setup is 100% for all as it depends on your driving style. If I was to get setup again now then I would probably spend a few hundred on the alignement tools so I could do stuff accurately and quicker without trial and error.
 

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Some good tips you got there :) they will be usefull..
Thinks its awsome that you are doing these write up's.

Thanks againg Royal.. :)

Looking forward too the next one !
 
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