valve durations?

are there any problems useing a spfi head on a mpfi engine? are the valve length and durations the same?
thanks in advance.

what are the heads? ill be able to find out for you. and what exactly do you mean by valve durations?

the heads are of the stock d15's one is spfi of a 4dr and one is the multiport for a crx. im trying to fix the crx. valve duration is defineded as the length of time a valve stays open or closed.

there are no problems with swapping the heads visa versa, there will be no valve clearance problems, the duration on the mpfi cam should be more than the dpfi. As for duration It should be around (220 degrees intake/ 225 degrees exhaust) <--just a guess..

oh yes, since you are saying that the CRX is a 1.5 liter and has MPFI. It may be an 8-valve motor. You DO NOT want to put a 16 valve head on an 8-valve motor that only has 2 valve reliefs in the pistons...

thanks