Hey everyone I'm looking to pick up a 4th gen Si with the H23 for a around town DD. I already have a Hondata P28 S300 to tune with so I'm looking to get some minor things to up the torque in the car. Right now I'm planning an aem CAI, mandrel bent 2.5 in exhaust, high flow cat and headers. Looking at the megan headers right now and from what I read and searched for doing the 2.5 Collector mod seems to be the way to go for more HP gains, but does anyone know how this will effect the torque? Since this car is an around town car most the time its going to be in low-mid range so gainning 5 ponies up top isn't worth losing 10ft torque in that range. Ideally I would like to get the car to 200whp with around 200ft-lbs torque but that maybe a little high for what I'm willing to do.

 

200whp/200tq with an H23 and bolt ons? LOL!

 

200 ft/lbs will be really hard to hit. If you're just looking for fun on the street, don't worry about the numbers too much. The Megan header is a waste and won't gain you anything. Look into some mild cams, playing with the cam timing, a good header, and a good tune. Losing reciprocating mass should also give it a little more punch on the street, so think about flywheel, balance shafts, etc.

 

Magus, you'll be hard pressed getting a 200/200 to the wheel on the H23 without a bit of work. For bolt ons I'd expect a realistic 155/155 with a lot of attention to tuning particularly through a megan header on an H23.

Comrpession, cams and a quality race header are the primary limitations on the H23 IMO.

-P

 

the megan header is pretty much a DC isnt it? If so then this header does a lot more on an h23 then it does for an h22. Also if you wanted to pay more for a GREAT header, Bisi should be able to do something for you. You can Run a F22 header on an H23 right?