How similar are these heads?We got a 454 awhile back,unmolested,and it had a mixed set of heads,one being 049 the other 781.Has anyone else seen this before?I looked on mortec and 2 books that I have (How to build max performance Chevy rat motors & Big Block Chevy performance)and have noticed that they're a couple of cc.s off from each other here and there.I have the heads,someone else ended up with the block and internals.

you and i must have had our heads together. i have the same combo on a 454 i bougt 781 and a 049. was told the diff is so minute that i would not have a prob. but just knowing it myself bothers me. goodluck

The engine was in a car(Camaro) that ran very well,low/mid 7s on motor.Just kinda bothers me a little.I found a guy that will trade me an 049 for my 781,he said he had the same thing.Haven't seen his cyl. head yet,nor he mine.