d15b8 is the 88-91 crx hf 8 valve 62hp engine. slap a 16valve si head on it and it will be a screamer. but as you stated you dont know how to set cam timing i highly recomend you not to do the headswap as timing has to be perfect or bent valves will occur. almost sounds like your cam timing is either 1 or 2 tooth retarded. remove the timing belt and move the cam gear towards the radiator 1 tooth. if it gets better move it another tooth. kinda an easy way to do it. but what you are supposed to do is set the crank pulley single mark to line up with the arrow on the timing belt cover to be at tdc. the up mark on the cam gear should actually be angled slightly to the left not straight up.

 

my pulley has like 5 different marks on it, there are 3 together and then there are 2 together like 1/8" from the other 3. i still havent put a o2 sensor on it, i have to use some heat to get it out of the old exhaust manifold. i doubt it will help that much though it has a hard time starting and i doubt that has anything to do with the o2 sensor. i have been doing a lot of research and reading up on these engines now (a little late possibly) but is it possible that i did not have the timing set correctly and bent the valves and now that is what is giving me all my problems? if so i may attempt to get a z6 or y8 head for it but i dont want to pour more money into it when i could have just put a better engine in it to start with? this is agrivating lol

 

ok i have made some progress but not much i swapped heads with my original head but when it threw the rod i believe it damaged one of the valves on the #4 cylinder so that head was junk and i couldnt even get the motor to start with that head so i swapped back the used head that came with the engine i just bought, and i got it to fire back up again however it still has major problems,
1. it smokes white smoke out of the tailpipe expecially when you give it throttle. i also took the exhaust manifold off numerous times when i was swapping heads and it appears that there is like oil or something wet trailing out of the #3 exhaust opening.
2. it idles for about 10 seconds then picks up an erratic idle and starts loping idle high then low back and forth.. twice a cel light has come on and the engine dies, and wont restart unless you turn the key back and then it fires right up again.
3. it still bogs down when you try to open up the throttle. it kind of feels like you are letting too much air into the engine and it kills it, it has done this consistently since i put the new motor in no matter what i did. i was wondering if i am getting adequate fuel pressure. it just seems like its not firing quite right. is there something you are supposed to do to prime the fuel system after unhooking the fuel line from the fuel rail? i just re installed the line. anyone have any guesses what it could be? oh and does the computer on these cars store codes to read back if the light goes off?