Caster, Chamber, and ride height are all adjusted by placing shims underthe suspension arms.
You don't need trued tires to measure chamber all you need is an RPM chamber guage. Also you won't be able to check for coned tires with a straight edge, you need to use some type of accurate measuring device (most use a set of calipers)....
To get proper chamber you however do need to start with true tires.......
It was already postd within the last few days but here agian is how to figure proper chamber for the best tire wear......
1. Start the car set with proper ride height and caster, everytime you change caster you need to recheck/readjust chamber.....
2. Take a piece of chalk and make a mark across the tread width of the front tires every 1/3-1/4 way around the tire.
3. Make 2 laps around the track at race speed triing to follow the line you will be using in racing condition. ( much slower or too far of the driving line will give you improper readings)
4. Check your marks, the outer edge should be worn away and the inner edge will be visible.
5. Use a small piece of anything of small thickness as a shim (header cards, pieces of paper, buisness card... different thicknesses adjust chamber more of less) Cut it into a 3mm strip.
6. Place the "shim" under the suspension arm on the outside of the screws.....
7. Remark the tires and repeat until the car comes off the track with the mark worn off of the entire tread width, you may have to use thinner shims or thicker shims to get even tire wear......
8. Use an RPM chamber guage to check and record the setting, also record caster set-up, track comditions, and lay-out information (alot of sweepers, mostly tight, 2 right-handsweepers w/ severasl tight left handers....ect.) this way if the lay-out is changed and you come accross the same type of lay-out in the future you know where to set the chamber to avoid all of this testing.
Remember as I stated earlier if you changer caster you may also need to readjust chamber for even tire wear.....
Also you may need different chamber angles for each side if you do come across a lay-out that has more sweepers in 1 direction than the other.......