hello..im also new to celica..from what i understand the lift activates around 6000 rpm this activates a valve and switches to the high speed cam. my step dad wrecked the original engine that came with the car(2000 GT). i saved it before the car goes to the steel yard. so i decided to purchase a 2zz engine. i dont know even know what year or model it came from to be honest but the seller said it has 40,000 clicks in it. so i did a swap when it arrived without a hoist by the way. tricky since im a DIY kind a guy with a little experience with automotive. i have issues with the engine first thing after install. overheated..the engine was basically having a hard time to breathe. i firgit to fill in the coolant. but tap water worked fine after. next was the high idle sitting at 2000 rpm. so i did a clean on the intake but still problem remain. and i thought maybe its just the gauge.. i didnt replace the guage and the indicator it goes to 8000 rpm. anyways theres three sets of wires in the air intake departmentif im not mistaken.MAF sensir and twoother valves thats connected to the airbox. those air hoses are just not connected to any holes because i dont know which one is which even after googling it. but i think that one valve one the upper airbox solved it. i connected evap hose the one with green cap to one fitting in the valve and the other fitting to the throttle body.before i bypass the valve. because from what i read the IAC takes care of whatevr the valve is suppose to do. after that fix my idle now sitting at 1500.. which is a relief. now to answer your question. sorry i dont know whereto begin typing to share my insights regarding.i dont think its necessary to adjust the high speed cam to an earler stage or to activate sooner. unless remove the low speed cam. and for this engine theres no need for mods to get more power unless install supercharger. i think. and someone stile my catalytic. now im running/testing it with the smoke coming out from headers. and its really loud i mean loud. a bunch of fibre glass insulations for silencer helps.
