Check out Exile Racing for mods as there are quite a few out there now for the 2.5.. I do believe there is a turbo kit for the 2.5.  http://catalog.exileracing.com/product_info.php?cPath=163_164_265&products_id=570&osCsid=509b189f5f52b7d7b48237ec55efa3a0

Stock, your V6 car is 163hp so unless you have some mods 185 is a bit optimistic. 

There are some amazing things you can do to either of these engines and get a very good amount of horsepower out of either.  It all depends on what you are able to do and what you are able to spend.  I think to answer your true questions we need some more information like your skillset and how much you are willing to spend as you have asked an open ended question.  Good luck!

you don't have 185hp. You probably have 170-172. There are no performance chips for our car- ebay chips do a TPS modification that makes your TPS think you're pushing the throttle in further. But at WOT it's identical- just push the pedal further for the same effect! Intake is only worth a maximum of 3-5 horse power if that. In order to hit 185 you're looking at headers and a good tune. In order to hit 200 you'll need a 3.0l swap, intake, headers, 210cc injectors, and also a good tune. In order to hit 300 you're looking at an exileracing turbo kit, or RIPP mods SDS- i would not recommend the RIPP as you seem inexperienced (no offense!) and it's not a bolt on kit- the exile turbo is fully bolt on. Kit in mind if you want to go turbo you'll need to ditch the headers if you put them on. Your best bet is to save for a stage 2 turbo- everything is even pre-tuned for you! You will never get more than 210hp if you're damn lucky (probably only with 6G74 manifold swap) staying naturally aspirated. Sorry that's just a fact

well i KNOW i need a tune-up, i researched a LONG time about mods for the V6, read reviews, people who have tried, disbelieved, believed and i dont know what else. lemme ask tho. what is the quarter mile and 0-60 time for a stock V6 sebring?

1/4 mile, mid-high 17's

0-60, ~10 seconds.

there's a better way to "condense" air going into the cylinders. It's called boost, and that get's quite expensive. You aren't looking at anything less than $3000 to do it right.

http://www.exileracing.com

You can get an underdrive pulley, which under drives the crank. About $120, some hand tools, and some elbow grease will free up 5-7 hp at the crank, 3-4 at the wheels. CustomCarGrills makes the only one i'm aware of. The XIRacing headers I told you about will get you about ~20 hp, but are quite bitch to find nowadays and even harder to put on, $650. Superchips Icon is proabaly the easiest hp gain. You need to tap 4 wires and you can change the timing advance or retard $325 new. Plugs/wires, 1/2 hp $100. MSD Ignition $300, another 1/2hp. Exhaust, bosal makes the only cat-back right now, Exile is almost finished with thiers. You can get a shop to custom fab one for you, $350. Hi-flow cat, $100 from Sroufe7, he makes awesome bolt-on ones. Exile has them as well. $210 for a downpipe from Sroufe7, again awesome product, those three maybe getting you 10hp, and I'm being generous with that number.

So you spent about 2k to get 35hp on a good day. take 25% of that away to the tranny, and you're left with about 25hp to the wheels. That get's you to maybe 140-145  to the wheels. Swap a 3.0 in for good measure and you got yourself 170whp at the price of $3500. Basically it's not worth modding the car at all unless you go turbo. You can throw a turbo on top off all that and you'd have a fast car. But you've spent more on the car than the car is worth.

I'm not saying don't mod your car, I'm just saying you aren't going to get much power from it. Everything for our cars is availalable, even though most of has been monopolzed and you have to look deep for it.

If you setup a certain type of Intake/Cold Air Intake, the maximum you'll ever get is about 10, but thats pushing it.. I've rarely saw someone get 10 hp outta an intake. It usually is about 5hp.. I have close to 170 in my Avenger, but of course, I got an K&N complete Intake, plus some odds and ends stuff put in there to give me a few here and there =) But of course its probably down to about 165 after the wear and tear on the engine, but I do keep it pretty rested, and I know it runs good.. Found out yesterday =).. A Cummins Diesel and a Powerstroke coming behind u at 95 mph is pretty scary, im sure u'll find out how fast your car can go when u have no way out haha =)

If you port and polish your heads, also a three or a five angle valve job and port match your intake ports.  You can also balance and blue print the engine.  Those are the only mods that will give you a sinificant amount of power while staying naturally asperated.

hmm, I'm not sure..hopefully one of the guys in here does know and can help out. and by the way...how many ppl actually do this stuff tho? the polishing, and valve jobs and what not.