I just changed my shocks and springs to koni sports and eibach springs.They lower the car about 1 inch all around.Also have hotchkis front and rear sways.So I was wandering if anyone autocrosses with a similar setup and what alignment specs they use.Any help is appreciated.

 

I'm in a similar spot as you. I have konis and Tiens but no sways. Need a good Auto-x alignment setup.

 

anybody?

 

STATIC Misalignment sometimes called alignment is the misadjustment of suspension to allow the suspension to be TRUE under typical thrust loads going straight at 55-60 mph on a highway. Performance cars add extra caster to increase self aligning torque to " return to straight ahead AFTER a curve and to gain negative camber and STATIC negative camber to position a tire for optimal camber [-0.5] as the body rolls and compresses the springs.

Toe in becomes neutral as the bushing push back and Toe in increases under deceleration and braking.

The point is that factory misalignment specs are for the average car not for a lowered [stiffer sprung] car or a car used exclusively for some special application such as skid pad or autocross.

Lowering body usually changes the bump steer relationship between the rack and the tie road end..........not important if you are on a bump free track and have enough spring stiffness so the body doesn't roll.

One must develop misalignment numbers that suit tire and vehicle differences.
What is best for autocross will be brutal on tires if driven on the street........some compromise will be necessary.

http://www.hummingbirds.net/alignment.html
http://www.tirerack.com/tires/tirete...e.jsp?techid=4

 

If you don't have aftermarket A-Arms you are stuck. The stock Z comes with NO front camber adjustment.

Lowering the car should give it more negative camber. Negative camber (to a limit) will increase your ability to corner. The downside of negative camber is you will have faster tire wear on the inside of the tire. So there is a compramise. What that is you need to decided.
But Q45tech is right, -.5 is great for tire wear (that is why most manufacture suggest this alignment), where as -2 to -3 degrees is great for performance.

 

When I lowered my car about the same as you did, the problem was not camber but toe. True the camber changed to a more negative value, but that is what you want for autocross. Bad/aggressive toe settings will eat tires much faster than aggressive camber settings. Unlike camber though, toe is adjustable both front and rear, so I would recommend that you get it checked.

As for some general settings for autocross, it is going to depend on the driver. I would start with some conservative settings and go from there. Maybe a slight amount of toe in in the rear and either 0 toe or slight toe out on the front. As for camber, you are stuck with what it is at in the front. In the rear you can change it slightly, I would try for -1.5 to -2 in the rear.