I know that i have to replace my b18b head with the b18c head. but dont you also have to change the computer on the car to control vtec? And if i do then how much does the cpu cost? thanks in advance

(this is my first post here. hey to all)

 

Yes you do have to change the ECU...."computer".....

 

doesn't have to be just b18c1 head...you can also use b18c5, b16a, or even b17.
and yes you must change your ECU.

Do some searching on this board and you'll find ALOT of info on Ls/vtec setups

 

how much do the price of the ecu usualy run for?

 

The price varies on what ECU you want.

Search around, you can find almost anything in the archives.

 

its not totally necessary to change ecu's, but it will unlock ur new motors potential more, i would just re-chip ur existing ls ecu for a higher redline, and buy a v-afc and wire that for full vtec adjustability and more control of ur fuel. theyre getting really cheap on ebay for like $225, compared to a chipped p28 or p72 for $250. also be very careful of which block u have, i beleive 90-93 ls blocks have knock sensors, but if u have a 94+ ls block they dont have knock sensors which GSR ecu's will throw a code for??