alright i dont know if you mean top end power or swerving on the road, but your throttle cable and timing are the two main possibilities as far as power, and struts, springs, front axles, tie rod ends would be my first guesses on steering. Dont attempt a conversion slash frankenstein engine as far as VTEC head to H23 block, you will have to do some crazy mods not for avid tuners and if your gonna do all that yourself goodluck, and if your payin' someone else than with the money your about to spend just buy the whole H22A Engine and put all aftermarket internals in it and drop that in for the same price, thats your best reassuring bang for the buck, just remember when you do drop a redline 7.5 engine in versus a redline 6.5rpm engine your going to need proper tuning as well as stronger applications in many different aspects to run properly for a long period of time, goodluck let me know if you have any questions about the possible leads in the top part mentioned?!