Ludespeed.com is the right place to go for info like that, i think its easier just to do a lude/vtec setup like what ludespeed did than to swap the stock motor for another DOHC Vtec since the older preludes were heavy they need a lot of torque to get them moving, which a b16a or b18c are not the best canidates for that, that is why preludes always came with 2.0 L motors and bigger, the Lude/vtec setup is just like the crv/vtec and ls/vtec setups, but it makes a shit load of torque and hp cause of the 2.0L size, if your looking into that let me know, i have a milled for higher compression b16a head complete minus valve cover and cams for $400+shipping, it was leakdown tested on a stock block and checked out good, i don't need this any more as i am going with a B20B Turbo setup