I want a big improvement. I autocross. I'm a nub who doesnt know the details.

My guess is that just lowering springs alone would suck ass. Anyone disagree?

How much does a full suspesion cost, give me brands, details, I know jack about this stuff.

Check the rule book. That will tell you what you are allowed to change and what you can't. In SCCA Solo II Stock class, you cant change much. Front sway bar, shocks, tire alignment settings and not much more. Again, study the rulebook.

I dont care about class. I just want to be extremely impressed by my car.

The best mod you can make is to the driver. What good would are the suspension bits if you can't use them to full effect? :confused:

SO far, the best improvement I made on my car was the Racing Beat suspension package (F/R Sway bars, springs, front sway bar endlinks). Car went from very good handling to outstanding. Also have the Koni shocks option now. Heard the Mazdaspeed springs & suspension are very good as well.

alnielsen is correct. If you plan on competeing with your car then you want to make sure that you haven't made upgrades that would stop you from competeing.

If you are simlpy looking to increase the way the vehicle handles then you have several option depending on the level of performance that you want. You could start with simple upgrades and change just the springs or you can do a complete suspension upgrade and use adjustable coil over units with swaybars. If you click on the link i have attaced below you will be able to see all of the suspension parts that the Tire Rack sells for the 6 speed 8. Another factor that you should also remember is that the stiffer you make the suspension for better handling, the worse the ride quality for every day use.

http://www.tirerack.com/suspension/Susptabl.jsp?autoMake=Mazda&autoModel=RX8+6-speed&autoYear=2004&category=Shocks&category=Springs&category=CoilOver&category=AntiRoll&autoModClar=&brand=all

Every post in this thread is bang on in it's own right. I changed coilovers and sways, but kept the stock braces and struts. Chucked the stock rims/tyres and replaced with slightly wider but lighter Volks, and sticky AD07's. The end result was a huge improvement in ride and handling, but that's just me, you're you ;)