Okay, heres the deal. I blew my bottom end on my u.s. motor and got a j-spec. I then blew my valvetrain on my j-spec motor. So then I put the u.s. spec head on the j-spec bottom end (this is my first time ever having an engine in pieces the way i did). I put it in the car and it starts but it sounds and smells like a very strong weedwacker. Like a 2-stroke engine or something. Im sure it is timing related but what is the "secret" to doing the timing chain. I did it by the fsm but I guess maybe I screwed something up. Im wondering if anyone has any insight to this problem and could tell me some pointers. Are there any sure-fire ways to getting the timing chain right? Also it idles for hours but if you give it gas once, it will rev, but then drops to 0 rpm and you have to keep gassing it to keep it going and it never gets its idle back till you let the car sit off for a while and then start it again. Also...I have holes drilled out on my intake manifold for connecting my direct port nitrous to, and if I take my fingers and plug them up the idle drops extremely low and often cuts off. PLEASE HELP.

I don't know about the rest of it, but I would highly suggest plugging up the holes for your direct-port setup. If they're uncapped, you're creating an ungodly vacuum leak and letting in unmetered air.

Which will make the car run just like you described above.

Cap those babies up and see what happens. I think NOS uses 1/16 holes. Just buy some 1/16 bolts and seal those holes up. Hope this helps.

Cap the NOS holes up, and check your cam timing. Please let us know what happens next.