hi everyone. ive decided to go ahead and get a couple mods for my car now that i've gotten my sounds to a satisfactory point. im thinking about the following:
-ztube
-k&n filter
-stillen sways

does anyone know of any negatives with any of these?

i searched already and didnt find anything except one thread (https://g35driver.com/forums/reviews/34155-z-tube-stock-filter.html) w/ the z-tube. in it... they gave a warning for ztube/popcharger and referred to another thread but the link didnt work. can some people confirm the z-tube is safe and will not give problems?

as far as the stillen bars go, anyone have any noise issues with them? (ive heard good things...just want to make sure before i drop the $)

 

The z-tube is fine, I believe where the problem lies is with the pop charger and rubbing against the ac lines.