i have a 2005 sedan with the stock "sport suspension" and 18" wheels
how much improvement can be gainedwith aftermarket springs/shocks,sway bars and what would you recommend?

thanks

very much can be improved, even with only a set of OEM 350Z springs you'll feel a big difference. With the oem Z springs, this is what the sport suspension should have been when they designed the car.
-GP-

see my sig... ride improved a lot... handling did also.... just don't forget to get wheels aligned....

I have the 2003 Sport Suspension. Stillen Sways greatly improved the handeling. The GTSPEC bars made it even better! Wheels and tires make it all work

You can get night-and-day differences.

Any single change will help a lot (springs, struts, sway bars, wider low-profile tires) but all of them make it a new world.

so, as with the Z tube intake, the springs off a 350Z will bolt on no problems to the sedan? what model year range will work?

Yes, 350z springs will bolt on with no problems. If you already have a sport suspension, people get the unrevised springs off a 350z ( 2003 to 2004) so they can use the same OEM sport shocks. However, if you get revised 350z springs (2004+ to 2006) than you will need to replace your shocks, due to the higher spring rate in the rear.

I am going to be installing 350z springs in the front and sport coupe springs (from a 2003 to 2004) in the rear on my sedan next Friday.

so how will the handling be with 19" wider rims? lowered on tein basics? will the handles be worse, or improved? i was thinking of getting a front strut bar.

The handling will be much better, but with the larger wheels, there is added weight, affecting the acceleration of the car.
-GP-

Handling will be greatly improved. The ride will not be as smooth but it's a trade off most of us are willing to make. It's not bad, just more of a sports car feel.

any aftermarket suspension part for this car will make a NOTICABLE difference in handling. I have spent total $400 on the suspension and couldn't be happier. As my sig says I went sideways for good 5 seconds on the freeway (because of a DUMB bitch) and i couln't believe how controllable the car was and managed to stay in one lane.
So answer is there will be a day and night difference.

thats good, bc i was kinda regretting ordering my rims bc i thought handling would be compromised. i think i should also get some sways. anyone have any recommendations on sway bars?

+1 for the stillen sways. probably one of the best mods you can do for the G

so where can i purchase some sway bars. i looked on everythingg35.com and i dont see the stillen sways for the sedans, only the coupes. any feedback on the eibachs or other brands?

all the sways are the same for 350z, coupe and sedan.