aight heres the deal the f23a1 is the vtec and so is the f23a4 although the f23a4 is the ulev(ultra low emissions vehicle) thats also what i got in my car

the f23a1 has 150 hp and the f23a4 has 148 not much a difference thank god

check out this website for more engine codes
http://www.torontoracing.ca/video/tech_hndacodes.html

 

damn freakin schemers......i want the money thats worth 2 hp back. Also, the ULEV gets 148 ft lbs of torque instead of the 152 in the regular sohc vtec.

 

listen to yourself... you're jealous of SOHC... haha

 

a $150 CAI, Injen or AEM will gain you +4wheel HP, +2 if it's the AUTO

 

Do a search, I posted in here about it.

 

yeah, the f23a4 is the ulev model. also, from what I understand, there's no physical differences between the engines, only the ECU's. and maybe the exhaust manifold, but I don't think so.

 

Only thing that makes it worthwhile is the noise.

 

F23a1 and F23a4 are identical save for the exhaust manifold. THe a4 manifold holds in more heat and back pressure (This helps out the cat). Swap for an aftermarket header or pickup an a1 manifold online and your set to go with getting back your 2hp

 

its not just 2 hp!! its 2 hp AND 4 ft lbs or torque buddy!!! that is some SERIOUS POWER!:naughty:

 

lol