funny idlin issue

[TheOne]

ok, car is 93 240sx, 93 block with 96 head(sorta ported on the intake), the previous 93 head was warped beyond repair.

problem: after i replaced the head with the 96 head, i can't get it to idle right, whenever i take out the clutch, the rpms stay @ about 900rpm for a sec or 2, then it drops to 700, then after a couple more secs it drops to 500, and stays there till i move, i believe this is caused by either a semi-clogged IACV, or bad timing. when the engine is cold, it'll idle @ 6-800rpms(not fluctuating though), whenever i turn on the A/C after the engine is warmed up, even when turnin it to max a/c, the engine idle stays at around 700rpm, doesn't go up to 1000+- like it used to just before the head change, the a/c however does cool, and cools pretty good.

i believe the idlin issue is timing related, i don't think i got the timing right cause every time i would take out the tps, the engine would idle @ over 1500rpm's, even when tryin to adjust with the iacv, it wouldn't go back down unless retarded the timing.(which i did try but still didn't seem to work)

ps. this is a 5sp with an auto ecu.(to take out the rpm/speed limiter, i still have the manual & know the line to splice just in case.)

[TheOne]

c'mon, i know somebody here knows why this happens!