heyy
i just got a lexus is300
im planning on doin AEM intake
Tanabe exhaust

wht r other mods i can do to get this thing alot faster

 

hm...there's headers, bigger throttle body, cam gears. Doin n/a mods wouldn't get your is goin really fast, just a lil bit faster. If you want your car to go really fast, might as well go boost. But for preference for headers, i'd say go for mazzuri, they are so far the best headers for the IS. They run for about 600, but theres a group buy on my.is for about 470 w/ shipping. Also since your gettin an AEM intake, you could look into engine management systems. For an alternative to that, you could go with the SRT intake that comes with an ECU, that way you don't have to waste money/time on getting an emanage unit and tuning it, because the ECU already comes tuned. Check over at my.is, there's alot of forums there with tons of mods and how to install, hp gains and all that stuff.

 

^^^
agree...
if you want to go fast, save up and go boost
most n/a mods will only give you slight hp increases
good luck

 

I understand you being eager to make your IS faster, god knows I feel the same damn way, have for a while. But when you modify the performance of you IS please don't rush it, and use the correct, quality parts and much care when installing if you do indeed install yourself.
Aside from that, I would definitly go with a Mazzuri header, I would get a custom exhaust made, or just go with the Tanabe Super Medallion or a Carson Tuning exhaust.
If you tell us exactly how much power you want to gain, we can better/more spefically answer your question.
Hope this helped!
-sm5sfe