In the middle of rebuilding a JD 440IC. Is it possible to put the higher compression late head on an early engine? Does anybody know what the horsepower increase is? I have both a late and early complete engine but the late (original, I think) engine is stuck...the early engine (assuming it is a match to the clutch housing it was bolted to) runs but I was going to re-ring it before I put it in the crawler. I bought the complete crawler and spare engine as a package so I can't be 100% sure of originality......the stuck engine has .040 over pistons in it so I think it will have to be re-sleeved....I can't get the pistons to budge and will probably destroy them getting them out. I haven't removed the cylinder head on the early motor yet. I assume I will be able to see the difference once I do.......?