thanks to all you guys i fixed my surging idle problem. turned out it was too simple to be obvious. see, when i put in the new engine and started it for the first time, the idle was so low, it would die. so i screwed that little screw with the locking nut on it in til it idled without dying. well then after warming up, it surged. i backed the screw out to lower the idle and now it idles fine with no surging.
the other problem i have been having isnt really a problem, just an observation and it did it with the old engine. while idling, you hear subtle skipping. not noticeable enough to cause any changes in rpm but almost like a really quiet backfire but with a deeep sound and i notice it happening about every 4-5 seconds. when i rev it up, it still does it a bit. dont know what that's all about but it just sticks in the back of my mind at times.
the last thing i noticed is a sort of a clanging sound when i abruptly step on the gas. the clang sounds like a knock in the engine and only does it for the instant the gas is pressed. after that , the rev is normal and it doesnt do it if i slowly rev the engine, but only when i stomp it. any ideas???

 

c'mon,someone's gotta know!