The F20/22 engines are so well tuned from the factory that adding simple bolt-ons is going to give minute gains if any....and you'll spend a lot to get the ones that actually increase power. Just boost it

 

Some mods will decrease power, but most will increase power slightly. As stated, the dc header and hks are known to lower power. People will generally make the trade off with the hks because of how awesome it sounds. I don't know why people buy the dc header. A high flow cat or resonated test pipe will yield less gains than a test pipe, but some prefer the quitter characteristics of them (I run a resonated test pipe), but all will make gains over an oem cat. Some cams will yield a higher peak hp but will lower the mid range power.
To me, that trade off is not worth it, if the mid range loss is too much. I would rather increase mid range than top end. If a part could increase 5-7 whp from 3500-6000, but lose 3 whp from 7500-9000, I would take that trade off (if I was still na). That is my opinion though, most could care less about mid range and only fixate on top end (the ego booster).

 

i got an invidia test pipe and q300 exhaust..about to buy the K&N FIPK intake...as far as power gains..they are minimal but there...def. no lose in power thats for sure..plus the sound the car makes now is incredible!!

 

Get 4.77 gear set, light weight wheels, light weight exhaust, and have them all install at the same time. The next drve will feel like you got a motor swap.

 

You can spend $2000 to go from 240HP to 255HP. Relative to other cars, modest gains in this car are expensive. Also keep in mind that swapping out the stock wheels for heavier ones will make your car slower. I can personally attest to this.

Outside of a tune and a simple bolt on or two, I wouldn't recommend any other power adders for this car. It just isn't worth the money, IMO.

 

I like how people only talk about the peak gains, as if the entire powerband doesn't become better / more useable. I love my 135lbs of tq @ 2500 rpms, even if I only made 25hp @ peak. It didn't come cheap though, as I've spent about $3000 in boltons/tuning.

 

Finally, someone else that cares about midrange.
135ft lbs at 2500 is not worth only 25hp at peak
That is like a crazy turbo diesel moped.

 

I bought (imo) the best sounding intake and exhaust.... and bought a berk hfc when my oem cat took a dump.

Is my car faster than stock? Probably. Does it sound better? HA. yes.

 

I gained 22whp peak and more power across the entire range and I spent little over a grand in total. Night and day difference from stock.

 

00-05 ECU has no 02 feedback in open loop/WOT where bolt on parts matter, so the result is you CAN run too lean. So yes, needing to add fuel from other sources such as anything from a simple adjustable rate fpr to a full ems with injectors depending on level of breathing modification. The only area in which the Honda ecu will add or subtract fuel given a particular driving environment or modification is in closed loop, which is a 14.7 fuel target, and that closed loop is in play at less then 50% throttle.

So Utah and you are both misinformed apparently.

If you spend personal time tuning this car, you understand this. If you don't, your not going to have a very successful tuning session.

00-01 ecu run the most conservative tune/ high fueling from the factory and show the most gains from breathing mods, simply because there is more then enough fuel already present to balance the afr without going overlean with typical bolt ons. 02-03 ecu were dialed in a bit leaner and why simply swapping them out with an otherwise stock 00-01 car will usually yield about 5whp over most the powerband, but also still show some gains with simple bolt ons. 04-05 ap2 are dialed in even leaner and doesn't take much but a Test Pipe to start running into over lean conditions, and that's where you can start losing power, because you have gone past "lean best" where the car makes max power before it falls into over lean condition.

There is a difference between a bolt on that flows poorly, robbing you of power from stock, vs a bolt on that flows better then OEM but the OEM ecu cant provide you the added fuel you need to see the benefit.

For NA guys, understanding the nuances of your particular year S2000 stock ECU and what you are bolting to it is key in extracting the most from it, and of course then being able to deliver sound and proper advice to others looking to understanding how to recreate that without looking at it as lucky or voodoo.