The easiest upgrade for this car is a DOHC vtec head. Use the existing block for a LS\VTEC setup. Very popular and puts out pretty good numbers. You have all the accessories in teh current car. Just pickup a used DOHC VTEC head on ebay for $500-$700. Basically bolts on. Get a new head gasket and new vtec timing belt. Distributor etc should work fine with new head.