Downtuned

I understand the 250 isn't the most powerful car out there, but I am looking to do something to the engine not only for a small boost in performance, but also to be able to hear the engine a bit more. Would a cold air do it for me, or would I need to invest in a new exhaust?

Any links to parts would be appreciated.

Hoovey689

iTrader: (16)

Intake, Exhaust, Headers are all you can really do. Expect "roughly" 20hp from those 3. Otherwise trade in for a 350

heyarms

iTrader: (5)

I have fujita intake, PPE headers and JoeZ racing exhaust on my is250, it definitely sounds a lot better now. An intake is definitely a cheap start and they produce a good deal of noise up front at higher rpm's.

FWIW, intake headers and exhaust will net more than 20hp, but not too terribly much. If I recall JoeZ gives around ~12whp and PPE headers gained ~15whp on a 250 (?) and JoeZ or FSport intake gives 5whp. Not much tp gain with these cars as you probably know, but it's still fun to drive

And here's a short rev clip of my setup:

Kurtz

iTrader: (1)

Joe Z exhaust is 10-12 hp far as I know... 5 from the intake... then 10-18 from the headers depending on whose dynos you go by... so 25-35 hp gain (and probably closer to the 25, given they won't all necessarily stack 1 for 1)

The downside is all that stuff together, besides being illegal in all 50 states (cept the intake, which is only illegal in CA), also runs close to $3000 installed... which isn't much less then the price gap 250->350, which would've added 102 hp.

KillaIS250

iTrader: (1)

Intake + headers + Joe-Z full exhaust if you want the most power and a good (loud) sound.

Still wont do much because the IS250 isn't able to be tuned, but you'll get a slight power boost. Next best option is to get a 350 for the extra power, and slap on a good exhaust for the sound

Gaugster

Headers and exhaust are a good place to start.